/*
 * $Header: /home/cvs/jakarta-tomcat-jasper/jasper2/src/share/org/apache/jasper/compiler/Generator.java,v 1.218 2004/02/03 08:27:43 remm Exp $
 * $Revision: 1.218 $
 * $Date: 2004/02/03 08:27:43 $
 *
 * ====================================================================
 * 
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights 
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:  
 *       "This product includes software developed by the 
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written 
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */
package org.apache.jasper.compiler;

import java.beans.BeanInfo;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Vector;

import javax.servlet.jsp.tagext.TagAttributeInfo;
import javax.servlet.jsp.tagext.TagInfo;
import javax.servlet.jsp.tagext.TagVariableInfo;
import javax.servlet.jsp.tagext.VariableInfo;

import org.apache.jasper.Constants;
import org.apache.jasper.JasperException;
import org.apache.jasper.JspCompilationContext;
import org.apache.jasper.runtime.JspRuntimeLibrary;
import org.xml.sax.Attributes;

/**
 * Generate Java source from Nodes
 *
 * @author Anil K. Vijendran
 * @author Danno Ferrin
 * @author Mandar Raje
 * @author Rajiv Mordani
 * @author Pierre Delisle
 * @author Kin-man Chung
 * @author Jan Luehe
 * @author Shawn Bayern
 * @author Mark Roth
 * @author Denis Benoit
 */

class Generator {

    private static final Class[] OBJECT_CLASS = { Object.class };
    private ServletWriter out;
    private ArrayList methodsBuffered;
    private FragmentHelperClass fragmentHelperClass;
    private ErrorDispatcher err;
    private BeanRepository beanInfo;
    private JspCompilationContext ctxt;
    private boolean isPoolingEnabled;
    private boolean breakAtLF;
    private PageInfo pageInfo;
    private int maxTagNesting;
    private Vector tagHandlerPoolNames;
    private GenBuffer charArrayBuffer;

    /**
     * @param s the input string
     * @return quoted and escaped string, per Java rule
     */
    static String quote(String s) {

        if (s == null)
            return "null";

        return '"' + escape(s) + '"';
    }

    /**
     * @param s the input string
     * @return escaped string, per Java rule
     */
    static String escape(String s) {

        if (s == null)
            return "";

        StringBuffer b = new StringBuffer();
        for (int i = 0; i < s.length(); i++) {
            char c = s.charAt(i);
            if (c == '"')
                b.append('\\').append('"');
            else if (c == '\\')
                b.append('\\').append('\\');
            else if (c == '\n')
                b.append('\\').append('n');
            else if (c == '\r')
                b.append('\\').append('r');
            else
                b.append(c);
        }
        return b.toString();
    }

    /**
     * Single quote and escape a character
     */
    static String quote(char c) {

        StringBuffer b = new StringBuffer();
        b.append('\'');
        if (c == '\'')
            b.append('\\').append('\'');
        else if (c == '\\')
            b.append('\\').append('\\');
        else if (c == '\n')
            b.append('\\').append('n');
        else if (c == '\r')
            b.append('\\').append('r');
        else
            b.append(c);
        b.append('\'');
        return b.toString();
    }

    /**
     * Generates declarations.  This includes "info" of the page directive,
     * and scriptlet declarations.
     */
    private void generateDeclarations(Node.Nodes page) throws JasperException {

        class DeclarationVisitor extends Node.Visitor {

            private boolean getServletInfoGenerated = false;

            /*
             * Generates getServletInfo() method that returns the value of the
             * page directive's 'info' attribute, if present.
             *
             * The Validator has already ensured that if the translation unit
             * contains more than one page directive with an 'info' attribute,
             * their values match.
             */
            public void visit(Node.PageDirective n) throws JasperException {

                if (getServletInfoGenerated) {
                    return;
                }

                String info = n.getAttributeValue("info");
                if (info == null)
                    return;

                getServletInfoGenerated = true;
                out.printil("public String getServletInfo() {");
                out.pushIndent();
                out.printin("return ");
                out.print(quote(info));
                out.println(";");
                out.popIndent();
                out.printil("}");
                out.println();
            }

            public void visit(Node.Declaration n) throws JasperException {
                n.setBeginJavaLine(out.getJavaLine());
                out.printMultiLn(new String(n.getText()));
                out.println();
                n.setEndJavaLine(out.getJavaLine());
            }

            // Custom Tags may contain declarations from tag plugins.
            public void visit(Node.CustomTag n) throws JasperException {
                if (n.useTagPlugin()) {
                    if (n.getAtSTag() != null) {
                        n.getAtSTag().visit(this);
                    }
                    visitBody(n);
                    if (n.getAtETag() != null) {
                        n.getAtETag().visit(this);
                    }
                } else {
                    visitBody(n);
                }
            }
        }

        out.println();
        page.visit(new DeclarationVisitor());
    }

    /**
     * Compiles list of tag handler pool names.
     */
    private void compileTagHandlerPoolList(Node.Nodes page)
        throws JasperException {

        class TagHandlerPoolVisitor extends Node.Visitor {

            private Vector names;

            /*
             * Constructor
             *
             * @param v Vector of tag handler pool names to populate
             */
            TagHandlerPoolVisitor(Vector v) {
                names = v;
            }

            /*
             * Gets the name of the tag handler pool for the given custom tag
             * and adds it to the list of tag handler pool names unless it is
             * already contained in it.
             */
            public void visit(Node.CustomTag n) throws JasperException {

                if (!n.implementsSimpleTag()) {
                    String name =
                        createTagHandlerPoolName(
                            n.getPrefix(),
                            n.getLocalName(),
                            n.getAttributes());
                    n.setTagHandlerPoolName(name);
                    if (!names.contains(name)) {
                        names.add(name);
                    }
                }
                visitBody(n);
            }

            /*
             * Creates the name of the tag handler pool whose tag handlers may
             * be (re)used to service this action.
             *
             * @return The name of the tag handler pool
             */
            private String createTagHandlerPoolName(
                String prefix,
                String shortName,
                Attributes attrs) {
                String poolName = null;

                if (prefix.indexOf('-') >= 0)
                    prefix = JspUtil.replace(prefix, '-', "$1");
                if (prefix.indexOf('.') >= 0)
                    prefix = JspUtil.replace(prefix, '.', "$2");

                if (shortName.indexOf('-') >= 0)
                    shortName = JspUtil.replace(shortName, '-', "$1");
                if (shortName.indexOf('.') >= 0)
                    shortName = JspUtil.replace(shortName, '.', "$2");
                if (shortName.indexOf(':') >= 0)
                    shortName = JspUtil.replace(shortName, ':', "$3");

                poolName = "_jspx_tagPool_" + prefix + "_" + shortName;
                if (attrs != null) {
                    String[] attrNames = new String[attrs.getLength()];
                    for (int i = 0; i < attrNames.length; i++) {
                        attrNames[i] = attrs.getQName(i);
                    }
                    Arrays.sort(attrNames, Collections.reverseOrder());
                    for (int i = 0; i < attrNames.length; i++) {
                        poolName = poolName + "_" + attrNames[i];
                    }
                }
                return poolName;
            }
        }

        page.visit(new TagHandlerPoolVisitor(tagHandlerPoolNames));
    }

    private void declareTemporaryScriptingVars(Node.Nodes page)
        throws JasperException {

        class ScriptingVarVisitor extends Node.Visitor {

            private Vector vars;

            ScriptingVarVisitor() {
                vars = new Vector();
            }

            public void visit(Node.CustomTag n) throws JasperException {

                if (n.getCustomNestingLevel() > 0) {
                    TagVariableInfo[] tagVarInfos = n.getTagVariableInfos();
                    VariableInfo[] varInfos = n.getVariableInfos();

                    if (varInfos.length > 0) {
                        for (int i = 0; i < varInfos.length; i++) {
                            String varName = varInfos[i].getVarName();
                            String tmpVarName =
                                "_jspx_"
                                    + varName
                                    + "_"
                                    + n.getCustomNestingLevel();
                            if (!vars.contains(tmpVarName)) {
                                vars.add(tmpVarName);
                                out.printin(varInfos[i].getClassName());
                                out.print(" ");
                                out.print(tmpVarName);
                                out.print(" = ");
                                out.print(null);
                                out.println(";");
                            }
                        }
                    } else {
                        for (int i = 0; i < tagVarInfos.length; i++) {
                            String varName = tagVarInfos[i].getNameGiven();
                            if (varName == null) {
                                varName =
                                    n.getTagData().getAttributeString(
                                        tagVarInfos[i].getNameFromAttribute());
                            } else if (
                                tagVarInfos[i].getNameFromAttribute()
                                    != null) {
                                // alias
                                continue;
                            }
                            String tmpVarName =
                                "_jspx_"
                                    + varName
                                    + "_"
                                    + n.getCustomNestingLevel();
                            if (!vars.contains(tmpVarName)) {
                                vars.add(tmpVarName);
                                out.printin(tagVarInfos[i].getClassName());
                                out.print(" ");
                                out.print(tmpVarName);
                                out.print(" = ");
                                out.print(null);
                                out.println(";");
                            }
                        }
                    }
                }

                visitBody(n);
            }
        }

        page.visit(new ScriptingVarVisitor());
    }

    /**
     * Generates the _jspInit() method for instantiating the tag handler pools.
     * For tag file, _jspInit has to be invoked manually, and the ServletConfig
     * object explicitly passed.
     */
    private void generateInit() {

        if (ctxt.isTagFile()) {
            out.printil("private void _jspInit(ServletConfig config) {");
        } else {
            out.printil("public void _jspInit() {");
        }

        out.pushIndent();
        for (int i = 0; i < tagHandlerPoolNames.size(); i++) {
            out.printin((String)tagHandlerPoolNames.elementAt(i));
            out.print(
                " = org.apache.jasper.runtime.TagHandlerPool.getTagHandlerPool(");
            if (ctxt.isTagFile()) {
                out.print("config");
            } else {
                out.print("getServletConfig()");
            }
            out.println(");");
        }
        out.popIndent();
        out.printil("}");
        out.println();
    }

    /**
     * Generates the _jspDestroy() method which is responsible for calling the
     * release() method on every tag handler in any of the tag handler pools.
     */
    private void generateDestroy() {

        out.printil("public void _jspDestroy() {");
        out.pushIndent();
        for (int i = 0; i < tagHandlerPoolNames.size(); i++) {
            out.printin((String)tagHandlerPoolNames.elementAt(i));
            out.println(".release();");
        }
        out.popIndent();
        out.printil("}");
        out.println();
    }

    /**
     * Generate preamble package name
     * (shared by servlet and tag handler preamble generation)
     */
    private void genPreamblePackage(String packageName)
        throws JasperException {
        if (!"".equals(packageName) && packageName != null) {
            out.printil("package " + packageName + ";");
            out.println();
        }
    }

    /**
     * Generate preamble imports
     * (shared by servlet and tag handler preamble generation)
     */
    private void genPreambleImports() throws JasperException {
        Iterator iter = pageInfo.getImports().iterator();
        while (iter.hasNext()) {
            out.printin("import ");
            out.print((String)iter.next());
            out.println(";");
        }
        out.println();
    }

    /**
     * Generation of static initializers in preamble.
     * For example, dependant list, el function map, prefix map.
     * (shared by servlet and tag handler preamble generation)
     */
    private void genPreambleStaticInitializers() throws JasperException {
        // Static data for getDependants()
        out.printil("private static java.util.Vector _jspx_dependants;");
        out.println();
        List dependants = pageInfo.getDependants();
        Iterator iter = dependants.iterator();
        if (!dependants.isEmpty()) {
            out.printil("static {");
            out.pushIndent();
            out.printin("_jspx_dependants = new java.util.Vector(");
            out.print("" + dependants.size());
            out.println(");");
            while (iter.hasNext()) {
                out.printin("_jspx_dependants.add(\"");
                out.print((String)iter.next());
                out.println("\");");
            }
            out.popIndent();
            out.printil("}");
            out.println();
        }
    }

    /**
     * Declare tag handler pools (tags of the same type and with the same
     * attribute set share the same tag handler pool)
     * (shared by servlet and tag handler preamble generation)
     */
    private void genPreambleClassVariableDeclarations(String className)
        throws JasperException {
        if (isPoolingEnabled && !tagHandlerPoolNames.isEmpty()) {
            for (int i = 0; i < tagHandlerPoolNames.size(); i++) {
                out.printil(
                    "private org.apache.jasper.runtime.TagHandlerPool "
                        + tagHandlerPoolNames.elementAt(i)
                        + ";");
            }
            out.println();
        }
    }

    /**
     * Declare general-purpose methods
     * (shared by servlet and tag handler preamble generation)
     */
    private void genPreambleMethods() throws JasperException {
        // Method used to get compile time file dependencies
        out.printil("public java.util.List getDependants() {");
        out.pushIndent();
        out.printil("return _jspx_dependants;");
        out.popIndent();
        out.printil("}");
        out.println();

        if (isPoolingEnabled && !tagHandlerPoolNames.isEmpty()) {
            generateInit();
            generateDestroy();
        }
    }

    /**
     * Generates the beginning of the static portion of the servlet.
     */
    private void generatePreamble(Node.Nodes page) throws JasperException {

        String servletPackageName = ctxt.getServletPackageName();
        String servletClassName = ctxt.getServletClassName();
        String serviceMethodName = Constants.SERVICE_METHOD_NAME;

        // First the package name:
        genPreamblePackage(servletPackageName);

        // Generate imports
        genPreambleImports();

        // Generate class declaration
        out.printin("public final class ");
        out.print(servletClassName);
        out.print(" extends ");
        out.println(pageInfo.getExtends());
        out.printin(
            "    implements org.apache.jasper.runtime.JspSourceDependent");
        if (!pageInfo.isThreadSafe()) {
            out.println(",");
            out.printin("                 SingleThreadModel");
        }
        out.println(" {");
        out.pushIndent();

        // Class body begins here
        generateDeclarations(page);

        // Static initializations here
        genPreambleStaticInitializers();

        // Class variable declarations
        genPreambleClassVariableDeclarations(servletClassName);

        // Constructor
        //	generateConstructor(className);

        // Methods here
        genPreambleMethods();

        // Now the service method
        out.printin("public void ");
        out.print(serviceMethodName);
        out.println(
            "(HttpServletRequest request, HttpServletResponse response)");
        out.println("        throws java.io.IOException, ServletException {");

        out.pushIndent();
        out.println();

        // Local variable declarations
        out.printil("JspFactory _jspxFactory = null;");
        out.printil("PageContext pageContext = null;");
        if (pageInfo.isSession())
            out.printil("HttpSession session = null;");

        if (pageInfo.isErrorPage()) {
            out.printil(
                "Throwable exception = org.apache.jasper.runtime.JspRuntimeLibrary.getThrowable(request);");
        }

        out.printil("ServletContext application = null;");
        out.printil("ServletConfig config = null;");
        out.printil("JspWriter out = null;");
        out.printil("Object page = this;");

        // Number of tag object that need to be popped
        // XXX TODO: use a better criteria
        maxTagNesting = pageInfo.getMaxTagNesting();
        out.printil("JspWriter _jspx_out = null;");
        out.printil("PageContext _jspx_page_context = null;");
        out.println();

        declareTemporaryScriptingVars(page);
        out.println();

        out.printil("try {");
        out.pushIndent();

        out.printil("_jspxFactory = JspFactory.getDefaultFactory();");

        out.printin("response.setContentType(");
        out.print(quote(pageInfo.getContentType()));
        out.println(");");

        if (ctxt.getOptions().isXpoweredBy()) {
            out.printil("response.addHeader(\"X-Powered-By\", \"JSP/2.0\");");
        }

        out.printil(
            "pageContext = _jspxFactory.getPageContext(this, request, response,");
        out.printin("\t\t\t");
        out.print(quote(pageInfo.getErrorPage()));
        out.print(", " + pageInfo.isSession());
        out.print(", " + pageInfo.getBuffer());
        out.print(", " + pageInfo.isAutoFlush());
        out.println(");");
        out.printil("_jspx_page_context = pageContext;");

        out.printil("application = pageContext.getServletContext();");
        out.printil("config = pageContext.getServletConfig();");

        if (pageInfo.isSession())
            out.printil("session = pageContext.getSession();");
        out.printil("out = pageContext.getOut();");
        out.printil("_jspx_out = out;");
        out.println();
    }

    /**
     * Generates an XML Prolog, which includes an XML declaration and
     * an XML doctype declaration.
     */
    private void generateXmlProlog(Node.Nodes page) {

        /*
         * An XML declaration is generated under the following conditions:
         *
         * - 'omit-xml-declaration' attribute of <jsp:output> action is set to
         *   "no" or "false"
         * - JSP document without a <jsp:root>
         */
        String omitXmlDecl = pageInfo.getOmitXmlDecl();
        if ((omitXmlDecl != null && !JspUtil.booleanValue(omitXmlDecl))
            || (omitXmlDecl == null
                && page.getRoot().isXmlSyntax()
                && !pageInfo.hasJspRoot()
                && !ctxt.isTagFile())) {
            String cType = pageInfo.getContentType();
            String charSet = cType.substring(cType.indexOf("charset=") + 8);
            out.printil(
                "out.write(\"<?xml version=\\\"1.0\\\" encoding=\\\""
                    + charSet
                    + "\\\"?>\\n\");");
        }

        /*
         * Output a DOCTYPE declaration if the doctype-root-element appears.
         * If doctype-public appears:
         *     <!DOCTYPE name PUBLIC "doctypePublic" "doctypeSystem">
         * else
         *     <!DOCTYPE name SYSTEM "doctypeSystem" >
         */

        String doctypeName = pageInfo.getDoctypeName();
        if (doctypeName != null) {
            String doctypePublic = pageInfo.getDoctypePublic();
            String doctypeSystem = pageInfo.getDoctypeSystem();
            out.printin("out.write(\"<!DOCTYPE ");
            out.print(doctypeName);
            if (doctypePublic == null) {
                out.print(" SYSTEM \\\"");
            } else {
                out.print(" PUBLIC \\\"");
                out.print(doctypePublic);
                out.print("\\\" \\\"");
            }
            out.print(doctypeSystem);
            out.println("\\\">\\n\");");
        }
    }

    /*
     * Generates the constructor.
     * (shared by servlet and tag handler preamble generation)
     */
    private void generateConstructor(String className) {
        out.printil("public " + className + "() {");
        out.printil("}");
        out.println();
    }

    /**
     * A visitor that generates codes for the elements in the page.
     */
    class GenerateVisitor extends Node.Visitor {

        /*
         * Hashtable containing introspection information on tag handlers:
         *   <key>: tag prefix
         *   <value>: hashtable containing introspection on tag handlers:
         *              <key>: tag short name
         *              <value>: introspection info of tag handler for 
         *                       <prefix:shortName> tag
         */
        private Hashtable handlerInfos;

        private Hashtable tagVarNumbers;
        private String parent;
        private boolean isSimpleTagParent; // Is parent a SimpleTag?
        private String pushBodyCountVar;
        private String simpleTagHandlerVar;
        private boolean isSimpleTagHandler;
        private boolean isFragment;
        private boolean isTagFile;
        private ServletWriter out;
        private ArrayList methodsBuffered;
        private FragmentHelperClass fragmentHelperClass;
        private int methodNesting;
        private TagInfo tagInfo;
        private ClassLoader loader;
        private int charArrayCount;
        private HashMap textMap;

        /**
         * Constructor.
         */
        public GenerateVisitor(
            boolean isTagFile,
            ServletWriter out,
            ArrayList methodsBuffered,
            FragmentHelperClass fragmentHelperClass,
            ClassLoader loader,
            TagInfo tagInfo) {

            this.isTagFile = isTagFile;
            this.out = out;
            this.methodsBuffered = methodsBuffered;
            this.fragmentHelperClass = fragmentHelperClass;
            this.loader = loader;
            this.tagInfo = tagInfo;
            methodNesting = 0;
            handlerInfos = new Hashtable();
            tagVarNumbers = new Hashtable();
            textMap = new HashMap();
        }

        /**
         * Returns an attribute value, optionally URL encoded.  If
         * the value is a runtime expression, the result is the expression
         * itself, as a string.  If the result is an EL expression, we insert
         * a call to the interpreter.  If the result is a Named Attribute
         * we insert the generated variable name.  Otherwise the result is a
         * string literal, quoted and escaped.
         *
         * @param attr An JspAttribute object
         * @param encode true if to be URL encoded
         * @param expectedType the expected type for an EL evaluation
         *        (ignored for attributes that aren't EL expressions)
         */
        private String attributeValue(
            Node.JspAttribute attr,
            boolean encode,
            Class expectedType) {
            String v = attr.getValue();
            if (!attr.isNamedAttribute() && (v == null))
                return "";

            if (attr.isExpression()) {
                if (encode) {
                    return "org.apache.jasper.runtime.JspRuntimeLibrary.URLEncode(String.valueOf("
                        + v
                        + "), request.getCharacterEncoding())";
                }
                return v;
            } else if (attr.isELInterpreterInput()) {
                boolean replaceESC = v.indexOf(Constants.ESC) > 0;
                v =
                    JspUtil.interpreterCall(
                        this.isTagFile,
                        v,
                        expectedType,
                        attr.getEL().getMapName(),
                        false);
                // XXX ESC replacement hack
                if (replaceESC) {
                    v = "(" + v + ").replace(" + Constants.ESCStr + ", '$')";
                }
                if (encode) {
                    return "org.apache.jasper.runtime.JspRuntimeLibrary.URLEncode("
                        + v
                        + ", request.getCharacterEncoding())";
                }
                return v;
            } else if (attr.isNamedAttribute()) {
                return attr.getNamedAttributeNode().getTemporaryVariableName();
            } else {
                if (encode) {
                    return "org.apache.jasper.runtime.JspRuntimeLibrary.URLEncode("
                        + quote(v)
                        + ", request.getCharacterEncoding())";
                }
                return quote(v);
            }
        }

        /**
         * Prints the attribute value specified in the param action, in the
         * form of name=value string.
         *
         * @param n the parent node for the param action nodes.
         */
        private void printParams(Node n, String pageParam, boolean literal)
            throws JasperException {

            class ParamVisitor extends Node.Visitor {
                String separator;

                ParamVisitor(String separator) {
                    this.separator = separator;
                }

                public void visit(Node.ParamAction n) throws JasperException {

                    out.print(" + ");
                    out.print(separator);
                    out.print(" + ");
                    out.print(
                        "org.apache.jasper.runtime.JspRuntimeLibrary."
                            + "URLEncode("
                            + quote(n.getTextAttribute("name"))
                            + ", request.getCharacterEncoding())");
                    out.print("+ \"=\" + ");
                    out.print(attributeValue(n.getValue(), true, String.class));

                    // The separator is '&' after the second use
                    separator = "\"&\"";
                }
            }

            String sep;
            if (literal) {
                sep = pageParam.indexOf('?') > 0 ? "\"&\"" : "\"?\"";
            } else {
                sep = "((" + pageParam + ").indexOf('?')>0? '&': '?')";
            }
            if (n.getBody() != null) {
                n.getBody().visit(new ParamVisitor(sep));
            }
        }

        public void visit(Node.Expression n) throws JasperException {
            n.setBeginJavaLine(out.getJavaLine());
            out.printil("out.print(" + n.getText() + ");");
            n.setEndJavaLine(out.getJavaLine());
        }

        public void visit(Node.Scriptlet n) throws JasperException {
            n.setBeginJavaLine(out.getJavaLine());
            out.printMultiLn(n.getText());
            out.println();
            n.setEndJavaLine(out.getJavaLine());
        }

        public void visit(Node.ELExpression n) throws JasperException {
            n.setBeginJavaLine(out.getJavaLine());
            if (!pageInfo.isELIgnored()) {
                out.printil(
                    "out.write("
                        + JspUtil.interpreterCall(
                            this.isTagFile,
                            "${" + new String(n.getText()) + "}",
                            String.class,
                            n.getEL().getMapName(),
                            false)
                        + ");");
            } else {
                out.printil(
                    "out.write("
                        + quote("${" + new String(n.getText()) + "}")
                        + ");");
            }
            n.setEndJavaLine(out.getJavaLine());
        }

        public void visit(Node.IncludeAction n) throws JasperException {

            String flush = n.getTextAttribute("flush");
            Node.JspAttribute page = n.getPage();

            boolean isFlush = false; // default to false;
            if ("true".equals(flush))
                isFlush = true;

            n.setBeginJavaLine(out.getJavaLine());

            String pageParam;
            if (page.isNamedAttribute()) {
                // If the page for jsp:include was specified via
                // jsp:attribute, first generate code to evaluate
                // that body.
                pageParam =
                    generateNamedAttributeValue(page.getNamedAttributeNode());
            } else {
                pageParam = attributeValue(page, false, String.class);
            }

            // If any of the params have their values specified by
            // jsp:attribute, prepare those values first.
            Node jspBody = findJspBody(n);
            if (jspBody != null) {
                prepareParams(jspBody);
            } else {
                prepareParams(n);
            }

            out.printin(
                "org.apache.jasper.runtime.JspRuntimeLibrary.include(request, response, "
                    + pageParam);
            printParams(n, pageParam, page.isLiteral());
            out.println(", out, " + isFlush + ");");

            n.setEndJavaLine(out.getJavaLine());
        }

        /**
         * Scans through all child nodes of the given parent for
         * <param> subelements.  For each <param> element, if its value
         * is specified via a Named Attribute (<jsp:attribute>), 
         * generate the code to evaluate those bodies first.
         * <p>
         * If parent is null, simply returns.
         */
        private void prepareParams(Node parent) throws JasperException {
            if (parent == null)
                return;

            Node.Nodes subelements = parent.getBody();
            if (subelements != null) {
                for (int i = 0; i < subelements.size(); i++) {
                    Node n = subelements.getNode(i);
                    if (n instanceof Node.ParamAction) {
                        Node.Nodes paramSubElements = n.getBody();
                        for (int j = 0;
                            (paramSubElements != null)
                                && (j < paramSubElements.size());
                            j++) {
                            Node m = paramSubElements.getNode(j);
                            if (m instanceof Node.NamedAttribute) {
                                generateNamedAttributeValue(
                                    (Node.NamedAttribute)m);
                            }
                        }
                    }
                }
            }
        }

        /**
         * Finds the <jsp:body> subelement of the given parent node.
         * If not found, null is returned.
         */
        private Node.JspBody findJspBody(Node parent) throws JasperException {
            Node.JspBody result = null;

            Node.Nodes subelements = parent.getBody();
            for (int i = 0;
                (subelements != null) && (i < subelements.size());
                i++) {
                Node n = subelements.getNode(i);
                if (n instanceof Node.JspBody) {
                    result = (Node.JspBody)n;
                    break;
                }
            }

            return result;
        }

        public void visit(Node.ForwardAction n) throws JasperException {
            Node.JspAttribute page = n.getPage();

            n.setBeginJavaLine(out.getJavaLine());

            out.printil("if (true) {"); // So that javac won't complain about
            out.pushIndent(); // codes after "return"

            String pageParam;
            if (page.isNamedAttribute()) {
                // If the page for jsp:forward was specified via
                // jsp:attribute, first generate code to evaluate
                // that body.
                pageParam =
                    generateNamedAttributeValue(page.getNamedAttributeNode());
            } else {
                pageParam = attributeValue(page, false, String.class);
            }

            // If any of the params have their values specified by
            // jsp:attribute, prepare those values first.
            Node jspBody = findJspBody(n);
            if (jspBody != null) {
                prepareParams(jspBody);
            } else {
                prepareParams(n);
            }

            out.printin("_jspx_page_context.forward(");
            out.print(pageParam);
            printParams(n, pageParam, page.isLiteral());
            out.println(");");
            if (isTagFile || isFragment) {
                out.printil("throw new SkipPageException();");
            } else {
                out.printil((methodNesting > 0) ? "return true;" : "return;");
            }
            out.popIndent();
            out.printil("}");

            n.setEndJavaLine(out.getJavaLine());
            // XXX Not sure if we can eliminate dead codes after this.
        }

        public void visit(Node.GetProperty n) throws JasperException {
            String name = n.getTextAttribute("name");
            String property = n.getTextAttribute("property");

            n.setBeginJavaLine(out.getJavaLine());

            if (beanInfo.checkVariable(name)) {
                // Bean is defined using useBean, introspect at compile time
                Class bean = beanInfo.getBeanType(name);
                String beanName = JspUtil.getCanonicalName(bean);
                java.lang.reflect.Method meth =
                    JspRuntimeLibrary.getReadMethod(bean, property);
                String methodName = meth.getName();
                out.printil(
                    "out.write(org.apache.jasper.runtime.JspRuntimeLibrary.toString("
                        + "((("
                        + beanName
                        + ")_jspx_page_context.findAttribute("
                        + "\""
                        + name
                        + "\"))."
                        + methodName
                        + "())));");
            } else {
                // The object could be a custom action with an associated
                // VariableInfo entry for this name.
                // Get the class name and then introspect at runtime.
                out.printil(
                    "out.write(org.apache.jasper.runtime.JspRuntimeLibrary.toString"
                        + "(org.apache.jasper.runtime.JspRuntimeLibrary.handleGetProperty"
                        + "(_jspx_page_context.findAttribute(\""
                        + name
                        + "\"), \""
                        + property
                        + "\")));");
            }

            n.setEndJavaLine(out.getJavaLine());
        }

        public void visit(Node.SetProperty n) throws JasperException {
            String name = n.getTextAttribute("name");
            String property = n.getTextAttribute("property");
            String param = n.getTextAttribute("param");
            Node.JspAttribute value = n.getValue();

            n.setBeginJavaLine(out.getJavaLine());

            if ("*".equals(property)) {
                out.printil(
                    "org.apache.jasper.runtime.JspRuntimeLibrary.introspect("
                        + "_jspx_page_context.findAttribute("
                        + "\""
                        + name
                        + "\"), request);");
            } else if (value == null) {
                if (param == null)
                    param = property; // default to same as property
                out.printil(
                    "org.apache.jasper.runtime.JspRuntimeLibrary.introspecthelper("
                        + "_jspx_page_context.findAttribute(\""
                        + name
                        + "\"), \""
                        + property
                        + "\", request.getParameter(\""
                        + param
                        + "\"), "
                        + "request, \""
                        + param
                        + "\", false);");
            } else if (value.isExpression()) {
                out.printil(
                    "org.apache.jasper.runtime.JspRuntimeLibrary.handleSetProperty("
                        + "_jspx_page_context.findAttribute(\""
                        + name
                        + "\"), \""
                        + property
                        + "\",");
                out.print(attributeValue(value, false, null));
                out.println(");");
            } else if (value.isELInterpreterInput()) {
                // We've got to resolve the very call to the interpreter
                // at runtime since we don't know what type to expect
                // in the general case; we thus can't hard-wire the call
                // into the generated code.  (XXX We could, however,
                // optimize the case where the bean is exposed with
                // <jsp:useBean>, much as the code here does for
                // getProperty.)

                // The following holds true for the arguments passed to
                // JspRuntimeLibrary.handleSetPropertyExpression():
                // - 'pageContext' is a VariableResolver.
                // - 'this' (either the generated Servlet or the generated tag
                //   handler for Tag files) is a FunctionMapper.
                out.printil(
                    "org.apache.jasper.runtime.JspRuntimeLibrary.handleSetPropertyExpression("
                        + "_jspx_page_context.findAttribute(\""
                        + name
                        + "\"), \""
                        + property
                        + "\", "
                        + quote(value.getValue())
                        + ", "
                        + "_jspx_page_context, "
                        + value.getEL().getMapName()
                        + ");");
            } else if (value.isNamedAttribute()) {
                // If the value for setProperty was specified via
                // jsp:attribute, first generate code to evaluate
                // that body.
                String valueVarName =
                    generateNamedAttributeValue(value.getNamedAttributeNode());
                out.printil(
                    "org.apache.jasper.runtime.JspRuntimeLibrary.introspecthelper("
                        + "_jspx_page_context.findAttribute(\""
                        + name
                        + "\"), \""
                        + property
                        + "\", "
                        + valueVarName
                        + ", null, null, false);");
            } else {
                out.printin(
                    "org.apache.jasper.runtime.JspRuntimeLibrary.introspecthelper("
                        + "_jspx_page_context.findAttribute(\""
                        + name
                        + "\"), \""
                        + property
                        + "\", ");
                out.print(attributeValue(value, false, null));
                out.println(", null, null, false);");
            }

            n.setEndJavaLine(out.getJavaLine());
        }

        public void visit(Node.UseBean n) throws JasperException {

            String name = n.getTextAttribute("id");
            String scope = n.getTextAttribute("scope");
            String klass = n.getTextAttribute("class");
            String type = n.getTextAttribute("type");
            Node.JspAttribute beanName = n.getBeanName();

            if (type == null) // if unspecified, use class as type of bean 
                type = klass;

            String scopename = "PageContext.PAGE_SCOPE"; // Default to page
            String lock = "_jspx_page_context";

            if ("request".equals(scope)) {
                scopename = "PageContext.REQUEST_SCOPE";
                lock = "request";
            } else if ("session".equals(scope)) {
                scopename = "PageContext.SESSION_SCOPE";
                lock = "session";
            } else if ("application".equals(scope)) {
                scopename = "PageContext.APPLICATION_SCOPE";
                lock = "application";
            }

            n.setBeginJavaLine(out.getJavaLine());

            // Declare bean
            out.printin(type);
            out.print(' ');
            out.print(name);
            out.println(" = null;");

            // Lock while getting or creating bean
            out.printin("synchronized (");
            out.print(lock);
            out.println(") {");
            out.pushIndent();

            // Locate bean from context
            out.printin(name);
            out.print(" = (");
            out.print(type);
            out.print(") _jspx_page_context.getAttribute(");
            out.print(quote(name));
            out.print(", ");
            out.print(scopename);
            out.println(");");

            // Create bean
            /*
             * Check if bean is alredy there
             */
            out.printin("if (");
            out.print(name);
            out.println(" == null){");
            out.pushIndent();
            if (klass == null && beanName == null) {
                /*
                 * If both class name and beanName is not specified, the bean
                 * must be found locally, otherwise it's an error
                 */
                out.printin(
                    "throw new java.lang.InstantiationException(\"bean ");
                out.print(name);
                out.println(" not found within scope\");");
            } else {
                /*
                 * Instantiate bean if not there
                 */
                String className;
                if (beanName != null) {
                    if (beanName.isNamedAttribute()) {
                        // If the value for beanName was specified via
                        // jsp:attribute, first generate code to evaluate
                        // that body.
                        className =
                            generateNamedAttributeValue(
                                beanName.getNamedAttributeNode());
                    } else {
                        className =
                            attributeValue(beanName, false, String.class);
                    }
                    out.printil("try {");
                    out.pushIndent();
                    out.printin(name);
                    out.print(" = (");
                    out.print(type);
                    out.print(") java.beans.Beans.instantiate(");
                    out.print("this.getClass().getClassLoader(), ");
                    out.print(className);
                    out.println(");");
                    out.popIndent();
                    /*
                     * Note: Beans.instantiate throws ClassNotFoundException
                     * if the bean class is abstract.
                     */
                    out.printil("} catch (ClassNotFoundException exc) {");
                    out.pushIndent();
                    out.printil(
                        "throw new InstantiationException(exc.getMessage());");
                    out.popIndent();
                    out.printil("} catch (Exception exc) {");
                    out.pushIndent();
                    out.printin("throw new ServletException(");
                    out.print("\"Cannot create bean of class \" + ");
                    out.print(className);
                    out.println(", exc);");
                    out.popIndent();
                    out.printil("}"); // close of try
                } else {
                    // Implies klass is not null
                    // Generate codes to instantiate the bean class
                    out.printin(name);
                    out.print(" = new ");
                    out.print(klass);
                    out.println("();");
                }
                /*
                 * Set attribute for bean in the specified scope
                 */
                out.printin("_jspx_page_context.setAttribute(");
                out.print(quote(name));
                out.print(", ");
                out.print(name);
                out.print(", ");
                out.print(scopename);
                out.println(");");

                // Only visit the body when bean is instantiated
                visitBody(n);
            }
            out.popIndent();
            out.printil("}");

            // End of lock block
            out.popIndent();
            out.printil("}");

            n.setEndJavaLine(out.getJavaLine());
        }

        /**
         * @return a string for the form 'attr = "value"'
         */
        private String makeAttr(String attr, String value) {
            if (value == null)
                return "";

            return " " + attr + "=\"" + value + '\"';
        }

        public void visit(Node.PlugIn n) throws JasperException {

            /**
             * A visitor to handle <jsp:param> in a plugin
             */
            class ParamVisitor extends Node.Visitor {

                private boolean ie;

                ParamVisitor(boolean ie) {
                    this.ie = ie;
                }

                public void visit(Node.ParamAction n) throws JasperException {

                    String name = n.getTextAttribute("name");
                    if (name.equalsIgnoreCase("object"))
                        name = "java_object";
                    else if (name.equalsIgnoreCase("type"))
                        name = "java_type";

                    n.setBeginJavaLine(out.getJavaLine());
                    // XXX - Fixed a bug here - value used to be output
                    // inline, which is only okay if value is not an EL
                    // expression.  Also, key/value pairs for the
                    // embed tag were not being generated correctly.
                    // Double check that this is now the correct behavior.
                    if (ie) {
                        // We want something of the form
                        // out.println( "<PARAM name=\"blah\" 
                        //     value=\"" + ... + "\">" );
                        out.printil(
                            "out.write( \"<PARAM name=\\\""
                                + escape(name)
                                + "\\\" value=\\\"\" + "
                                + attributeValue(
                                    n.getValue(),
                                    false,
                                    String.class)
                                + " + \"\\\">\" );");
                        out.printil("out.write(\"\\n\");");
                    } else {
                        // We want something of the form
                        // out.print( " blah=\"" + ... + "\"" );
                        out.printil(
                            "out.write( \" "
                                + escape(name)
                                + "=\\\"\" + "
                                + attributeValue(
                                    n.getValue(),
                                    false,
                                    String.class)
                                + " + \"\\\"\" );");
                    }

                    n.setEndJavaLine(out.getJavaLine());
                }
            }

            String type = n.getTextAttribute("type");
            String code = n.getTextAttribute("code");
            String name = n.getTextAttribute("name");
            Node.JspAttribute height = n.getHeight();
            Node.JspAttribute width = n.getWidth();
            String hspace = n.getTextAttribute("hspace");
            String vspace = n.getTextAttribute("vspace");
            String align = n.getTextAttribute("align");
            String iepluginurl = n.getTextAttribute("iepluginurl");
            String nspluginurl = n.getTextAttribute("nspluginurl");
            String codebase = n.getTextAttribute("codebase");
            String archive = n.getTextAttribute("archive");
            String jreversion = n.getTextAttribute("jreversion");

            String widthStr = null;
            if (width != null) {
                if (width.isNamedAttribute()) {
                    widthStr =
                        generateNamedAttributeValue(
                            width.getNamedAttributeNode());
                } else {
                    widthStr = attributeValue(width, false, String.class);
                }
            }

            String heightStr = null;
            if (height != null) {
                if (height.isNamedAttribute()) {
                    heightStr =
                        generateNamedAttributeValue(
                            height.getNamedAttributeNode());
                } else {
                    heightStr = attributeValue(height, false, String.class);
                }
            }

            if (iepluginurl == null)
                iepluginurl = Constants.IE_PLUGIN_URL;
            if (nspluginurl == null)
                nspluginurl = Constants.NS_PLUGIN_URL;

            n.setBeginJavaLine(out.getJavaLine());

            // If any of the params have their values specified by
            // jsp:attribute, prepare those values first.
            // Look for a params node and prepare its param subelements:
            Node.JspBody jspBody = findJspBody(n);
            if (jspBody != null) {
                Node.Nodes subelements = jspBody.getBody();
                if (subelements != null) {
                    for (int i = 0; i < subelements.size(); i++) {
                        Node m = subelements.getNode(i);
                        if (m instanceof Node.ParamsAction) {
                            prepareParams(m);
                            break;
                        }
                    }
                }
            }

            // XXX - Fixed a bug here - width and height can be set 
            // dynamically.  Double-check if this generation is correct.

            // IE style plugin
            // <OBJECT ...>
            // First compose the runtime output string 
            String s0 = "<OBJECT"
                    + makeAttr("classid", ctxt.getOptions().getIeClassId())
                    + makeAttr("name", name);

            String s1 = "";
            if (width != null) {
                s1 = " + \" width=\\\"\" + " + widthStr + " + \"\\\"\"";
            }

            String s2 = "";
            if (height != null) {
                s2 = " + \" height=\\\"\" + " + heightStr + " + \"\\\"\"";
            }

            String s3 = makeAttr("hspace", hspace)
                    + makeAttr("vspace", vspace)
                    + makeAttr("align", align)
                    + makeAttr("codebase", iepluginurl)
                    + '>';

            // Then print the output string to the java file
            out.printil(
                "out.write(" + quote(s0) + s1 + s2 + " + " + quote(s3) + ");");
            out.printil("out.write(\"\\n\");");

            // <PARAM > for java_code
            s0 = "<PARAM name=\"java_code\"" + makeAttr("value", code) + '>';
            out.printil("out.write(" + quote(s0) + ");");
            out.printil("out.write(\"\\n\");");

            // <PARAM > for java_codebase
            if (codebase != null) {
                s0 = "<PARAM name=\"java_codebase\""
                        + makeAttr("value", codebase)
                        + '>';
                out.printil("out.write(" + quote(s0) + ");");
                out.printil("out.write(\"\\n\");");
            }

            // <PARAM > for java_archive
            if (archive != null) {
                s0 = "<PARAM name=\"java_archive\""
                        + makeAttr("value", archive)
                        + '>';
                out.printil("out.write(" + quote(s0) + ");");
                out.printil("out.write(\"\\n\");");
            }

            // <PARAM > for type
            s0 = "<PARAM name=\"type\""
                    + makeAttr(
                        "value",
                        "application/x-java-"
                            + type
                            + ";"
                            + ((jreversion == null)
                                ? ""
                                : "version=" + jreversion))
                    + '>';
            out.printil("out.write(" + quote(s0) + ");");
            out.printil("out.write(\"\\n\");");

            /*
             * generate a <PARAM> for each <jsp:param> in the plugin body
             */
            if (n.getBody() != null)
                n.getBody().visit(new ParamVisitor(true));

            /*
             * Netscape style plugin part
             */
            out.printil("out.write(" + quote("<COMMENT>") + ");");
            out.printil("out.write(\"\\n\");");
            s0 = "<EMBED"
                    + makeAttr(
                        "type",
                        "application/x-java-"
                            + type
                            + ";"
                            + ((jreversion == null)
                                ? ""
                                : "version=" + jreversion))
                    + makeAttr("name", name);

            // s1 and s2 are the same as before.

            s3 = makeAttr("hspace", hspace)
                    + makeAttr("vspace", vspace)
                    + makeAttr("align", align)
                    + makeAttr("pluginspage", nspluginurl)
                    + makeAttr("java_code", code)
                    + makeAttr("java_codebase", codebase)
                    + makeAttr("java_archive", archive);
            out.printil(
                "out.write(" + quote(s0) + s1 + s2 + " + " + quote(s3) + ");");

            /*
             * Generate a 'attr = "value"' for each <jsp:param> in plugin body
             */
            if (n.getBody() != null)
                n.getBody().visit(new ParamVisitor(false));

            out.printil("out.write(" + quote("/>") + ");");
            out.printil("out.write(\"\\n\");");

            out.printil("out.write(" + quote("<NOEMBED>") + ");");
            out.printil("out.write(\"\\n\");");

            /*
             * Fallback
             */
            if (n.getBody() != null) {
                visitBody(n);
                out.printil("out.write(\"\\n\");");
            }

            out.printil("out.write(" + quote("</NOEMBED>") + ");");
            out.printil("out.write(\"\\n\");");

            out.printil("out.write(" + quote("</COMMENT>") + ");");
            out.printil("out.write(\"\\n\");");

            out.printil("out.write(" + quote("</OBJECT>") + ");");
            out.printil("out.write(\"\\n\");");

            n.setEndJavaLine(out.getJavaLine());
        }

        public void visit(Node.NamedAttribute n) throws JasperException {
            // Don't visit body of this tag - we already did earlier.
        }

        public void visit(Node.CustomTag n) throws JasperException {

            // Use plugin to generate more efficient code if there is one.
            if (n.useTagPlugin()) {
                generateTagPlugin(n);
                return;
            }

            TagHandlerInfo handlerInfo = getTagHandlerInfo(n);

            // Create variable names
            String baseVar =
                createTagVarName(n.getQName(), n.getPrefix(), n.getLocalName());
            String tagEvalVar = "_jspx_eval_" + baseVar;
            String tagHandlerVar = "_jspx_th_" + baseVar;
            String tagPushBodyCountVar = "_jspx_push_body_count_" + baseVar;

            // If the tag contains no scripting element, generate its codes
            // to a method.
            ServletWriter outSave = null;
            Node.ChildInfo ci = n.getChildInfo();
            if (ci.isScriptless() && !ci.hasScriptingVars()) {
                // The tag handler and its body code can reside in a separate
                // method if it is scriptless and does not have any scripting
                // variable defined.

                String tagMethod = "_jspx_meth_" + baseVar;

                // Generate a call to this method
                out.printin("if (");
                out.print(tagMethod);
                out.print("(");
                if (parent != null) {
                    out.print(parent);
                    out.print(", ");
                }
                out.print("_jspx_page_context");
                if (pushBodyCountVar != null) {
                    out.print(", ");
                    out.print(pushBodyCountVar);
                }
                out.println("))");
                out.pushIndent();
                out.printil((methodNesting > 0) ? "return true;" : "return;");
                out.popIndent();

                // Set up new buffer for the method
                outSave = out;
                /* For fragments, their bodies will be generated in fragment
                   helper classes, and the Java line adjustments will be done
                   there, hence they are set to null here to avoid double
                   adjustments.
                */
                GenBuffer genBuffer =
                    new GenBuffer(n, n.implementsSimpleTag()? null: n.getBody());
                methodsBuffered.add(genBuffer);
                out = genBuffer.getOut();

                methodNesting++;
                // Generate code for method declaration
                out.println();
                out.pushIndent();
                out.printin("private boolean ");
                out.print(tagMethod);
                out.print("(");
                if (parent != null) {
                    out.print("javax.servlet.jsp.tagext.JspTag ");
                    out.print(parent);
                    out.print(", ");
                }
                out.print("PageContext _jspx_page_context");
                if (pushBodyCountVar != null) {
                    out.print(", int[] ");
                    out.print(pushBodyCountVar);
                }
                out.println(")");
                out.printil("        throws Throwable {");
                out.pushIndent();

                // Initilaize local variables used in this method.
                out.printil("JspWriter out = _jspx_page_context.getOut();");
                generateLocalVariables(out, n);
            }

            if (n.implementsSimpleTag()) {
                generateCustomDoTag(n, handlerInfo, tagHandlerVar);
            } else {
                /*
                 * Classic tag handler: Generate code for start element, body,
                 * and end element
                 */
                generateCustomStart(
                    n,
                    handlerInfo,
                    tagHandlerVar,
                    tagEvalVar,
                    tagPushBodyCountVar);

                // visit body
                String tmpParent = parent;
                parent = tagHandlerVar;
                boolean isSimpleTagParentSave = isSimpleTagParent;
                isSimpleTagParent = false;
                String tmpPushBodyCountVar = null;
                if (n.implementsTryCatchFinally()) {
                    tmpPushBodyCountVar = pushBodyCountVar;
                    pushBodyCountVar = tagPushBodyCountVar;
                }
                boolean tmpIsSimpleTagHandler = isSimpleTagHandler;
                isSimpleTagHandler = false;

                visitBody(n);

                parent = tmpParent;
                isSimpleTagParent = isSimpleTagParentSave;
                if (n.implementsTryCatchFinally()) {
                    pushBodyCountVar = tmpPushBodyCountVar;
                }
                isSimpleTagHandler = tmpIsSimpleTagHandler;

                generateCustomEnd(
                    n,
                    tagHandlerVar,
                    tagEvalVar,
                    tagPushBodyCountVar);
            }

            if (ci.isScriptless() && !ci.hasScriptingVars()) {
                // Generate end of method
                if (methodNesting > 0) {
                    out.printil("return false;");
                }
                out.popIndent();
                out.printil("}");
                out.popIndent();

                methodNesting--;

                // restore previous writer
                out = outSave;
            }
        }

        private static final String SINGLE_QUOTE = "'";
        private static final String DOUBLE_QUOTE = "\\\"";

        public void visit(Node.UninterpretedTag n) throws JasperException {

            /*
             * Write begin tag
             */
            out.printin("out.write(\"<");
            out.print(n.getQName());

            Attributes attrs = n.getNonTaglibXmlnsAttributes();
            int attrsLen = (attrs == null) ? 0 : attrs.getLength();
            for (int i = 0; i < attrsLen; i++) {
                out.print(" ");
                out.print(attrs.getQName(i));
                out.print("=");
                String quote = DOUBLE_QUOTE;
                String value = attrs.getValue(i);
                if (value.indexOf('"') != -1) {
                    quote = SINGLE_QUOTE;
                }
                out.print(quote);
                out.print(value);
                out.print(quote);
            }

            attrs = n.getAttributes();
            attrsLen = (attrs == null) ? 0 : attrs.getLength();
            Node.JspAttribute[] jspAttrs = n.getJspAttributes();
            for (int i = 0; i < attrsLen; i++) {
                out.print(" ");
                out.print(attrs.getQName(i));
                out.print("=");
                if (jspAttrs[i].isELInterpreterInput()) {
                    out.print("\\\"\" + ");
                    out.print(attributeValue(jspAttrs[i], false, Object.class));
                    out.print(" + \"\\\"");
                } else {
                    String quote = DOUBLE_QUOTE;
                    String value = attrs.getValue(i);
                    if (value.indexOf('"') != -1) {
                        quote = SINGLE_QUOTE;
                    }
                    out.print(quote);
                    out.print(value);
                    out.print(quote);
                }
            }

            if (n.getBody() != null) {
                out.println(">\");");

                // Visit tag body
                visitBody(n);

                /*
                 * Write end tag
                 */
                out.printin("out.write(\"</");
                out.print(n.getQName());
                out.println(">\");");
            } else {
                out.println("/>\");");
            }
        }

        public void visit(Node.JspElement n) throws JasperException {

            // Compute attribute value string for XML-style and named
            // attributes
            Hashtable map = new Hashtable();
            Node.JspAttribute[] attrs = n.getJspAttributes();
            for (int i = 0; attrs != null && i < attrs.length; i++) {
                String attrStr = null;
                if (attrs[i].isNamedAttribute()) {
                    attrStr =
                        generateNamedAttributeValue(
                            attrs[i].getNamedAttributeNode());
                } else {
                    attrStr = attributeValue(attrs[i], false, Object.class);
                }
                String s =
                    " + \" "
                        + attrs[i].getName()
                        + "=\\\"\" + "
                        + attrStr
                        + " + \"\\\"\"";
                map.put(attrs[i].getName(), s);
            }

            // Write begin tag, using XML-style 'name' attribute as the
            // element name
            String elemName =
                attributeValue(n.getNameAttribute(), false, String.class);
            out.printin("out.write(\"<\"");
            out.print(" + " + elemName);

            // Write remaining attributes
            Enumeration enum = map.keys();
            while (enum.hasMoreElements()) {
                String attrName = (String)enum.nextElement();
                out.print((String)map.get(attrName));
            }

            // Does the <jsp:element> have nested tags other than
            // <jsp:attribute>
            boolean hasBody = false;
            Node.Nodes subelements = n.getBody();
            if (subelements != null) {
                for (int i = 0; i < subelements.size(); i++) {
                    Node subelem = subelements.getNode(i);
                    if (!(subelem instanceof Node.NamedAttribute)) {
                        hasBody = true;
                        break;
                    }
                }
            }
            if (hasBody) {
                out.println(" + \">\");");

                // Visit tag body
                visitBody(n);

                // Write end tag
                out.printin("out.write(\"</\"");
                out.print(" + " + elemName);
                out.println(" + \">\");");
            } else {
                out.println(" + \"/>\");");
            }
        }

        public void visit(Node.TemplateText n) throws JasperException {

            String text = n.getText();

            int textSize = text.length();
            if (textSize == 0) {
                return;
            }

            if (textSize <= 3) {
               // Special case small text strings
               n.setBeginJavaLine(out.getJavaLine());
               int lineInc = 0;
               for (int i = 0; i < textSize; i++) {
                   char ch = text.charAt(i);
                   out.printil("out.write(" + quote(ch) + ");");
                   if (i > 0) {
                       n.addSmap(lineInc);
                   }
                   if (ch == '\n') {
                       lineInc++;
                   }
               }
               n.setEndJavaLine(out.getJavaLine());
               return;
           }

            if (ctxt.getOptions().genStringAsCharArray()) {
               // Generate Strings as char arrays, for performance
                ServletWriter caOut;
                if (charArrayBuffer == null) {
                    charArrayBuffer = new GenBuffer();
                    caOut = charArrayBuffer.getOut();
                    caOut.pushIndent();
                    textMap = new HashMap();
                } else {
                    caOut = charArrayBuffer.getOut();
                }
                String charArrayName = (String) textMap.get(text);
                if (charArrayName == null) {
                    charArrayName = "_jspx_char_array_" + charArrayCount++;
                    textMap.put(text, charArrayName);
                    caOut.printin("static char[] ");
                    caOut.print(charArrayName);
                    caOut.print(" = ");
                    caOut.print(quote(text));
                    caOut.println(".toCharArray();");
                }

                n.setBeginJavaLine(out.getJavaLine());
                out.printil("out.write(" + charArrayName + ");");
                n.setEndJavaLine(out.getJavaLine());
                return;
            }

            n.setBeginJavaLine(out.getJavaLine());

            out.printin();
            StringBuffer sb = new StringBuffer("out.write(\"");
            int initLength = sb.length();
            int count = JspUtil.CHUNKSIZE;
            int srcLine = 0;	// relative to starting srouce line
            for (int i = 0; i < text.length(); i++) {
                char ch = text.charAt(i);
                --count;
                switch (ch) {
                    case '"' :
                        sb.append('\\').append('\"');
                        break;
                    case '\\' :
                        sb.append('\\').append('\\');
                        break;
                    case '\r' :
                        sb.append('\\').append('r');
                        break;
                    case '\n' :
                        sb.append('\\').append('n');
                        srcLine++;

                        if (breakAtLF || count < 0) {
                            // Generate an out.write() when see a '\n' in template
                            sb.append("\");");
                            out.println(sb.toString());
                            if (i < text.length() - 1) {
                                out.printin();
                            }
                            sb.setLength(initLength);
                            count = JspUtil.CHUNKSIZE;
                        }
                        // add a Smap for this line
                        n.addSmap(srcLine);
                        break;
                    case '\t' : // Not sure we need this
                        sb.append('\\').append('t');
                        break;
                    default :
                        sb.append(ch);
                }
            }

            if (sb.length() > initLength) {
                sb.append("\");");
                out.println(sb.toString());
            }

            n.setEndJavaLine(out.getJavaLine());
        }

        public void visit(Node.JspBody n) throws JasperException {
            if (n.getBody() != null) {
                if (isSimpleTagHandler) {
                    out.printin(simpleTagHandlerVar);
                    out.print(".setJspBody(");
                    generateJspFragment(n, simpleTagHandlerVar);
                    out.println(");");
                } else {
                    visitBody(n);
                }
            }
        }

        public void visit(Node.InvokeAction n) throws JasperException {

            // Copy virtual page scope of tag file to page scope of invoking
            // page
            out.printil(
                "((org.apache.jasper.runtime.JspContextWrapper) this.jspContext).syncBeforeInvoke();");

            // Invoke fragment
            String varReaderAttr = n.getTextAttribute("varReader");
            String varAttr = n.getTextAttribute("var");
            if (varReaderAttr != null || varAttr != null) {
                out.printil("_jspx_sout = new java.io.StringWriter();");
            } else {
                out.printil("_jspx_sout = null;");
            }
            out.printin(toGetterMethod(n.getTextAttribute("fragment")));
            out.println(".invoke(_jspx_sout);");

            // Store varReader in appropriate scope
            if (varReaderAttr != null || varAttr != null) {
                String scopeName = n.getTextAttribute("scope");
                out.printin("_jspx_page_context.setAttribute(");
                if (varReaderAttr != null) {
                    out.print(quote(varReaderAttr));
                    out.print(
                        ", new java.io.StringReader(_jspx_sout.toString())");
                } else {
                    out.print(quote(varAttr));
                    out.print(", _jspx_sout.toString()");
                }
                if (scopeName != null) {
                    out.print(", ");
                    out.print(getScopeConstant(scopeName));
                }
                out.println(");");
            }
        }

        public void visit(Node.DoBodyAction n) throws JasperException {

            // Copy virtual page scope of tag file to page scope of invoking
            // page
            out.printil(
                "((org.apache.jasper.runtime.JspContextWrapper) this.jspContext).syncBeforeInvoke();");

            // Invoke body
            String varReaderAttr = n.getTextAttribute("varReader");
            String varAttr = n.getTextAttribute("var");
            if (varReaderAttr != null || varAttr != null) {
                out.printil("_jspx_sout = new java.io.StringWriter();");
            } else {
                out.printil("_jspx_sout = null;");
            }
            out.printil("if (getJspBody() != null)");
            out.pushIndent();
            out.printil("getJspBody().invoke(_jspx_sout);");
            out.popIndent();

            // Store varReader in appropriate scope
            if (varReaderAttr != null || varAttr != null) {
                String scopeName = n.getTextAttribute("scope");
                out.printin("_jspx_page_context.setAttribute(");
                if (varReaderAttr != null) {
                    out.print(quote(varReaderAttr));
                    out.print(
                        ", new java.io.StringReader(_jspx_sout.toString())");
                } else {
                    out.print(quote(varAttr));
                    out.print(", _jspx_sout.toString()");
                }
                if (scopeName != null) {
                    out.print(", ");
                    out.print(getScopeConstant(scopeName));
                }
                out.println(");");
            }
        }

        public void visit(Node.AttributeGenerator n) throws JasperException {
            Node.CustomTag tag = n.getTag();
            Node.JspAttribute[] attrs = tag.getJspAttributes();
            for (int i = 0; attrs != null && i < attrs.length; i++) {
                if (attrs[i].getName().equals(n.getName())) {
                    out.print(
                        evaluateAttribute(
                            getTagHandlerInfo(tag),
                            attrs[i],
                            tag,
                            null));
                    break;
                }
            }
        }

        private TagHandlerInfo getTagHandlerInfo(Node.CustomTag n)
            throws JasperException {
            Hashtable handlerInfosByShortName =
                (Hashtable)handlerInfos.get(n.getPrefix());
            if (handlerInfosByShortName == null) {
                handlerInfosByShortName = new Hashtable();
                handlerInfos.put(n.getPrefix(), handlerInfosByShortName);
            }
            TagHandlerInfo handlerInfo =
                (TagHandlerInfo)handlerInfosByShortName.get(n.getLocalName());
            if (handlerInfo == null) {
                handlerInfo =
                    new TagHandlerInfo(n, n.getTagHandlerClass(), err);
                handlerInfosByShortName.put(n.getLocalName(), handlerInfo);
            }
            return handlerInfo;
        }

        private void generateTagPlugin(Node.CustomTag n)
            throws JasperException {
            if (n.getAtSTag() != null) {
                n.getAtSTag().visit(this);
            }
            visitBody(n);
            if (n.getAtETag() != null) {
                n.getAtETag().visit(this);
            }
        }

        private void generateCustomStart(
            Node.CustomTag n,
            TagHandlerInfo handlerInfo,
            String tagHandlerVar,
            String tagEvalVar,
            String tagPushBodyCountVar)
            throws JasperException {

            Class tagHandlerClass = handlerInfo.getTagHandlerClass();

            n.setBeginJavaLine(out.getJavaLine());
            out.printin("//  ");
            out.println(n.getQName());

            // Declare AT_BEGIN scripting variables
            declareScriptingVars(n, VariableInfo.AT_BEGIN);
            saveScriptingVars(n, VariableInfo.AT_BEGIN);

            String tagHandlerClassName =
                JspUtil.getCanonicalName(tagHandlerClass);
            out.printin(tagHandlerClassName);
            out.print(" ");
            out.print(tagHandlerVar);
            out.print(" = ");
            if (isPoolingEnabled) {
                out.print("(");
                out.print(tagHandlerClassName);
                out.print(") ");
                out.print(n.getTagHandlerPoolName());
                out.print(".get(");
                out.print(tagHandlerClassName);
                out.println(".class);");
            } else {
                out.print("new ");
                out.print(tagHandlerClassName);
                out.println("();");
            }

            generateSetters(n, tagHandlerVar, handlerInfo, false);

            if (n.implementsTryCatchFinally()) {
                out.printin("int[] ");
                out.print(tagPushBodyCountVar);
                out.println(" = new int[] { 0 };");
                out.printil("try {");
                out.pushIndent();
            }
            out.printin("int ");
            out.print(tagEvalVar);
            out.print(" = ");
            out.print(tagHandlerVar);
            out.println(".doStartTag();");

            if (!n.implementsBodyTag()) {
                // Synchronize AT_BEGIN scripting variables
                syncScriptingVars(n, VariableInfo.AT_BEGIN);
            }

            if (!n.hasEmptyBody()) {
                out.printin("if (");
                out.print(tagEvalVar);
                out.println(" != javax.servlet.jsp.tagext.Tag.SKIP_BODY) {");
                out.pushIndent();

                // Declare NESTED scripting variables
                declareScriptingVars(n, VariableInfo.NESTED);
                saveScriptingVars(n, VariableInfo.NESTED);

                if (n.implementsBodyTag()) {
                    out.printin("if (");
                    out.print(tagEvalVar);
                    out.println(
                        " != javax.servlet.jsp.tagext.Tag.EVAL_BODY_INCLUDE) {");
                    // Assume EVAL_BODY_BUFFERED
                    out.pushIndent();
                    out.printil("out = _jspx_page_context.pushBody();");
                    if (n.implementsTryCatchFinally()) {
                        out.printin(tagPushBodyCountVar);
                        out.println("[0]++;");
                    } else if (pushBodyCountVar != null) {
                        out.printin(pushBodyCountVar);
                        out.println("[0]++;");
                    }
                    out.printin(tagHandlerVar);
                    out.println(
                        ".setBodyContent((javax.servlet.jsp.tagext.BodyContent) out);");
                    out.printin(tagHandlerVar);
                    out.println(".doInitBody();");

                    out.popIndent();
                    out.printil("}");

                    // Synchronize AT_BEGIN and NESTED scripting variables
                    syncScriptingVars(n, VariableInfo.AT_BEGIN);
                    syncScriptingVars(n, VariableInfo.NESTED);

                } else {
                    // Synchronize NESTED scripting variables
                    syncScriptingVars(n, VariableInfo.NESTED);
                }

                if (n.implementsIterationTag()) {
                    out.printil("do {");
                    out.pushIndent();
                }
            }
        };

        private void generateCustomEnd(
            Node.CustomTag n,
            String tagHandlerVar,
            String tagEvalVar,
            String tagPushBodyCountVar) {

            if (!n.hasEmptyBody()) {
                if (n.implementsIterationTag()) {
                    out.printin("int evalDoAfterBody = ");
                    out.print(tagHandlerVar);
                    out.println(".doAfterBody();");

                    // Synchronize AT_BEGIN and NESTED scripting variables
                    syncScriptingVars(n, VariableInfo.AT_BEGIN);
                    syncScriptingVars(n, VariableInfo.NESTED);

                    out.printil(
                        "if (evalDoAfterBody != javax.servlet.jsp.tagext.BodyTag.EVAL_BODY_AGAIN)");
                    out.pushIndent();
                    out.printil("break;");
                    out.popIndent();

                    out.popIndent();
                    out.printil("} while (true);");
                }

                restoreScriptingVars(n, VariableInfo.NESTED);

                if (n.implementsBodyTag()) {
                    out.printin("if (");
                    out.print(tagEvalVar);
                    out.println(
                        " != javax.servlet.jsp.tagext.Tag.EVAL_BODY_INCLUDE)");
                    out.pushIndent();
                    out.printil("out = _jspx_page_context.popBody();");
                    if (n.implementsTryCatchFinally()) {
                        out.printin(tagPushBodyCountVar);
                        out.println("[0]--;");
                    } else if (pushBodyCountVar != null) {
                        out.printin(pushBodyCountVar);
                        out.println("[0]--;");
                    }
                    out.popIndent();
                }

                out.popIndent(); // EVAL_BODY
                out.printil("}");
            }

            out.printin("if (");
            out.print(tagHandlerVar);
            out.println(
                ".doEndTag() == javax.servlet.jsp.tagext.Tag.SKIP_PAGE)");
            out.pushIndent();
            if (isTagFile || isFragment) {
                out.printil("throw new SkipPageException();");
            } else {
                out.printil((methodNesting > 0) ? "return true;" : "return;");
            }
            out.popIndent();

            // Synchronize AT_BEGIN scripting variables
            syncScriptingVars(n, VariableInfo.AT_BEGIN);

            // TryCatchFinally
            if (n.implementsTryCatchFinally()) {
                out.popIndent(); // try
                out.printil("} catch (Throwable _jspx_exception) {");
                out.pushIndent();

                out.printin("while (");
                out.print(tagPushBodyCountVar);
                out.println("[0]-- > 0)");
                out.pushIndent();
                out.printil("out = _jspx_page_context.popBody();");
                out.popIndent();

                out.printin(tagHandlerVar);
                out.println(".doCatch(_jspx_exception);");
                out.popIndent();
                out.printil("} finally {");
                out.pushIndent();
                out.printin(tagHandlerVar);
                out.println(".doFinally();");
            }

            if (isPoolingEnabled) {
                out.printin(n.getTagHandlerPoolName());
                out.print(".reuse(");
                out.print(tagHandlerVar);
                out.println(");");
            }

            if (n.implementsTryCatchFinally()) {
                out.popIndent();
                out.printil("}");
            }

            // Declare and synchronize AT_END scripting variables (must do this
            // outside the try/catch/finally block)
            declareScriptingVars(n, VariableInfo.AT_END);
            syncScriptingVars(n, VariableInfo.AT_END);

            restoreScriptingVars(n, VariableInfo.AT_BEGIN);

            n.setEndJavaLine(out.getJavaLine());
        }

        private void generateCustomDoTag(
            Node.CustomTag n,
            TagHandlerInfo handlerInfo,
            String tagHandlerVar)
            throws JasperException {

            Class tagHandlerClass = handlerInfo.getTagHandlerClass();

            n.setBeginJavaLine(out.getJavaLine());
            out.printin("//  ");
            out.println(n.getQName());

            // Declare AT_BEGIN scripting variables
            declareScriptingVars(n, VariableInfo.AT_BEGIN);
            saveScriptingVars(n, VariableInfo.AT_BEGIN);

            String tagHandlerClassName =
                JspUtil.getCanonicalName(tagHandlerClass);
            out.printin(tagHandlerClassName);
            out.print(" ");
            out.print(tagHandlerVar);
            out.print(" = ");
            out.print("new ");
            out.print(tagHandlerClassName);
            out.println("();");

            generateSetters(n, tagHandlerVar, handlerInfo, true);

            // Set the body
            if (findJspBody(n) == null) {
                /*
                 * Encapsulate body of custom tag invocation in JspFragment
                 * and pass it to tag handler's setJspBody(), unless tag body
                 * is empty
                 */
                if (!n.hasEmptyBody()) {
                    out.printin(tagHandlerVar);
                    out.print(".setJspBody(");
                    generateJspFragment(n, tagHandlerVar);
                    out.println(");");
                }
            } else {
                /*
                 * Body of tag is the body of the <jsp:body> element.
                 * The visit method for that element is going to encapsulate
                 * that element's body in a JspFragment and pass it to
                 * the tag handler's setJspBody()
                 */
                String tmpTagHandlerVar = simpleTagHandlerVar;
                simpleTagHandlerVar = tagHandlerVar;
                boolean tmpIsSimpleTagHandler = isSimpleTagHandler;
                isSimpleTagHandler = true;
                visitBody(n);
                simpleTagHandlerVar = tmpTagHandlerVar;
                isSimpleTagHandler = tmpIsSimpleTagHandler;
            }

            out.printin(tagHandlerVar);
            out.println(".doTag();");

            restoreScriptingVars(n, VariableInfo.AT_BEGIN);

            // Synchronize AT_BEGIN scripting variables
            syncScriptingVars(n, VariableInfo.AT_BEGIN);

            // Declare and synchronize AT_END scripting variables
            declareScriptingVars(n, VariableInfo.AT_END);
            syncScriptingVars(n, VariableInfo.AT_END);

            n.setEndJavaLine(out.getJavaLine());
        }

        private void declareScriptingVars(Node.CustomTag n, int scope) {

            Vector vec = n.getScriptingVars(scope);
            if (vec != null) {
                for (int i = 0; i < vec.size(); i++) {
                    Object elem = vec.elementAt(i);
                    if (elem instanceof VariableInfo) {
                        VariableInfo varInfo = (VariableInfo)elem;
                        if (varInfo.getDeclare()) {
                            out.printin(varInfo.getClassName());
                            out.print(" ");
                            out.print(varInfo.getVarName());
                            out.println(" = null;");
                        }
                    } else {
                        TagVariableInfo tagVarInfo = (TagVariableInfo)elem;
                        if (tagVarInfo.getDeclare()) {
                            String varName = tagVarInfo.getNameGiven();
                            if (varName == null) {
                                varName =
                                    n.getTagData().getAttributeString(
                                        tagVarInfo.getNameFromAttribute());
                            } else if (
                                tagVarInfo.getNameFromAttribute() != null) {
                                // alias
                                continue;
                            }
                            out.printin(tagVarInfo.getClassName());
                            out.print(" ");
                            out.print(varName);
                            out.println(" = null;");
                        }
                    }
                }
            }
        }

        /*
         * This method is called as part of the custom tag's start element.
         *
         * If the given custom tag has a custom nesting level greater than 0,
         * save the current values of its scripting variables to 
         * temporary variables, so those values may be restored in the tag's
         * end element. This way, the scripting variables may be synchronized
         * by the given tag without affecting their original values.
         */
        private void saveScriptingVars(Node.CustomTag n, int scope) {
            if (n.getCustomNestingLevel() == 0) {
                return;
            }

            TagVariableInfo[] tagVarInfos = n.getTagVariableInfos();
            VariableInfo[] varInfos = n.getVariableInfos();
            if ((varInfos.length == 0) && (tagVarInfos.length == 0)) {
                return;
            }

            if (varInfos.length > 0) {
                for (int i = 0; i < varInfos.length; i++) {
                    if (varInfos[i].getScope() != scope)
                        continue;
                    String varName = varInfos[i].getVarName();
                    String tmpVarName =
                        "_jspx_" + varName + "_" + n.getCustomNestingLevel();
                    out.printin(tmpVarName);
                    out.print(" = ");
                    out.print(varName);
                    out.println(";");
                }
            } else {
                for (int i = 0; i < tagVarInfos.length; i++) {
                    if (tagVarInfos[i].getScope() != scope)
                        continue;
                    String varName = tagVarInfos[i].getNameGiven();
                    if (varName == null) {
                        varName =
                            n.getTagData().getAttributeString(
                                tagVarInfos[i].getNameFromAttribute());
                    } else if (tagVarInfos[i].getNameFromAttribute() != null) {
                        // alias
                        continue;
                    }
                    String tmpVarName =
                        "_jspx_" + varName + "_" + n.getCustomNestingLevel();
                    out.printin(tmpVarName);
                    out.print(" = ");
                    out.print(varName);
                    out.println(";");
                }
            }
        }

        /*
         * This method is called as part of the custom tag's end element.
         *
         * If the given custom tag has a custom nesting level greater than 0,
         * restore its scripting variables to their original values that were
         * saved in the tag's start element.
         */
        private void restoreScriptingVars(Node.CustomTag n, int scope) {
            if (n.getCustomNestingLevel() == 0) {
                return;
            }

            TagVariableInfo[] tagVarInfos = n.getTagVariableInfos();
            VariableInfo[] varInfos = n.getVariableInfos();
            if ((varInfos.length == 0) && (tagVarInfos.length == 0)) {
                return;
            }

            if (varInfos.length > 0) {
                for (int i = 0; i < varInfos.length; i++) {
                    if (varInfos[i].getScope() != scope)
                        continue;
                    String varName = varInfos[i].getVarName();
                    String tmpVarName =
                        "_jspx_" + varName + "_" + n.getCustomNestingLevel();
                    out.printin(varName);
                    out.print(" = ");
                    out.print(tmpVarName);
                    out.println(";");
                }
            } else {
                for (int i = 0; i < tagVarInfos.length; i++) {
                    if (tagVarInfos[i].getScope() != scope)
                        continue;
                    String varName = tagVarInfos[i].getNameGiven();
                    if (varName == null) {
                        varName =
                            n.getTagData().getAttributeString(
                                tagVarInfos[i].getNameFromAttribute());
                    } else if (tagVarInfos[i].getNameFromAttribute() != null) {
                        // alias
                        continue;
                    }
                    String tmpVarName =
                        "_jspx_" + varName + "_" + n.getCustomNestingLevel();
                    out.printin(varName);
                    out.print(" = ");
                    out.print(tmpVarName);
                    out.println(";");
                }
            }
        }

        /*
         * Synchronizes the scripting variables of the given custom tag for
         * the given scope.
         */
        private void syncScriptingVars(Node.CustomTag n, int scope) {
            TagVariableInfo[] tagVarInfos = n.getTagVariableInfos();
            VariableInfo[] varInfos = n.getVariableInfos();

            if ((varInfos.length == 0) && (tagVarInfos.length == 0)) {
                return;
            }

            if (varInfos.length > 0) {
                for (int i = 0; i < varInfos.length; i++) {
                    if (varInfos[i].getScope() == scope) {
                        out.printin(varInfos[i].getVarName());
                        out.print(" = (");
                        out.print(varInfos[i].getClassName());
                        out.print(") _jspx_page_context.findAttribute(");
                        out.print(quote(varInfos[i].getVarName()));
                        out.println(");");
                    }
                }
            } else {
                for (int i = 0; i < tagVarInfos.length; i++) {
                    if (tagVarInfos[i].getScope() == scope) {
                        String name = tagVarInfos[i].getNameGiven();
                        if (name == null) {
                            name =
                                n.getTagData().getAttributeString(
                                    tagVarInfos[i].getNameFromAttribute());
                        } else if (
                            tagVarInfos[i].getNameFromAttribute() != null) {
                            // alias
                            continue;
                        }
                        out.printin(name);
                        out.print(" = (");
                        out.print(tagVarInfos[i].getClassName());
                        out.print(") _jspx_page_context.findAttribute(");
                        out.print(quote(name));
                        out.println(");");
                    }
                }
            }
        }

        /*
         * Creates a tag variable name by concatenating the given prefix and
         * shortName and replacing '-' with "$1", '.' with "$2", and ':' with
         * "$3".
         */
        private String createTagVarName(
            String fullName,
            String prefix,
            String shortName) {
            if (prefix.indexOf('-') >= 0)
                prefix = JspUtil.replace(prefix, '-', "$1");
            if (prefix.indexOf('.') >= 0)
                prefix = JspUtil.replace(prefix, '.', "$2");

            if (shortName.indexOf('-') >= 0)
                shortName = JspUtil.replace(shortName, '-', "$1");
            if (shortName.indexOf('.') >= 0)
                shortName = JspUtil.replace(shortName, '.', "$2");
            if (shortName.indexOf(':') >= 0)
                shortName = JspUtil.replace(shortName, ':', "$3");

            synchronized (tagVarNumbers) {
                String varName = prefix + "_" + shortName + "_";
                if (tagVarNumbers.get(fullName) != null) {
                    Integer i = (Integer)tagVarNumbers.get(fullName);
                    varName = varName + i.intValue();
                    tagVarNumbers.put(fullName, new Integer(i.intValue() + 1));
                    return varName;
                } else {
                    tagVarNumbers.put(fullName, new Integer(1));
                    return varName + "0";
                }
            }
        }

        private String evaluateAttribute(
            TagHandlerInfo handlerInfo,
            Node.JspAttribute attr,
            Node.CustomTag n,
            String tagHandlerVar)
            throws JasperException {

            String attrValue = attr.getValue();
            if (attrValue == null) {
                if (attr.isNamedAttribute()) {
                    if (n.checkIfAttributeIsJspFragment(attr.getName())) {
                        // XXX - no need to generate temporary variable here
                        attrValue =
                            generateNamedAttributeJspFragment(
                                attr.getNamedAttributeNode(),
                                tagHandlerVar);
                    } else {
                        attrValue =
                            generateNamedAttributeValue(
                                attr.getNamedAttributeNode());
                    }
                } else {
                    return null;
                }
            }

            String localName = attr.getLocalName();

            Method m = null;
            Class[] c = null;
            if (attr.isDynamic()) {
                c = OBJECT_CLASS;
            } else {
                m = handlerInfo.getSetterMethod(localName);
                if (m == null) {
                    err.jspError(
                        n,
                        "jsp.error.unable.to_find_method",
                        attr.getName());
                }
                c = m.getParameterTypes();
                // XXX assert(c.length > 0)
            }

            if (attr.isExpression()) {
                // Do nothing
            } else if (attr.isNamedAttribute()) {
                if (!n.checkIfAttributeIsJspFragment(attr.getName())
                    && !attr.isDynamic()) {
                    attrValue =
                        convertString(
                            c[0],
                            attrValue,
                            localName,
                            handlerInfo.getPropertyEditorClass(localName),
                            true);
                }
            } else if (attr.isELInterpreterInput()) {
                // run attrValue through the expression interpreter
                boolean replaceESC = attrValue.indexOf(Constants.ESC) > 0;
                attrValue =
                    JspUtil.interpreterCall(
                        this.isTagFile,
                        attrValue,
                        c[0],
                        attr.getEL().getMapName(),
                        false);
                // XXX hack: Replace ESC with '$'
                if (replaceESC) {
                    attrValue =
                        "("
                            + attrValue
                            + ").replace("
                            + Constants.ESCStr
                            + ", '$')";
                }
            } else {
                attrValue =
                    convertString(
                        c[0],
                        attrValue,
                        localName,
                        handlerInfo.getPropertyEditorClass(localName),
                        false);
            }
            return attrValue;
        }

        /**
         * Generate code to create a map for the alias variables
         * @return the name of the map
         */
        private String generateAliasMap(Node.CustomTag n, String tagHandlerVar)
            throws JasperException {

            TagVariableInfo[] tagVars = n.getTagVariableInfos();
            String aliasMapVar = null;

            boolean aliasSeen = false;
            for (int i = 0; i < tagVars.length; i++) {

                String nameFrom = tagVars[i].getNameFromAttribute();
                if (nameFrom != null) {
                    String aliasedName = n.getAttributeValue(nameFrom);
                    if (aliasedName == null)
                        continue;

                    if (!aliasSeen) {
                        out.printin("java.util.HashMap ");
                        aliasMapVar = tagHandlerVar + "_aliasMap";
                        out.print(aliasMapVar);
                        out.println(" = new java.util.HashMap();");
                        aliasSeen = true;
                    }
                    out.printin(aliasMapVar);
                    out.print(".put(");
                    out.print(quote(tagVars[i].getNameGiven()));
                    out.print(", ");
                    out.print(quote(aliasedName));
                    out.println(");");
                }
            }
            return aliasMapVar;
        }

        private void generateSetters(
            Node.CustomTag n,
            String tagHandlerVar,
            TagHandlerInfo handlerInfo,
            boolean simpleTag)
            throws JasperException {

            // Set context
            if (simpleTag) {
                // Generate alias map 
                String aliasMapVar = null;
                if (n.isTagFile()) {
                    aliasMapVar = generateAliasMap(n, tagHandlerVar);
                }
                out.printin(tagHandlerVar);
                if (aliasMapVar == null) {
                    out.println(".setJspContext(_jspx_page_context);");
                } else {
                    out.print(".setJspContext(_jspx_page_context, ");
                    out.print(aliasMapVar);
                    out.println(");");
                }
            } else {
                out.printin(tagHandlerVar);
                out.println(".setPageContext(_jspx_page_context);");
            }

            // Set parent
            if (!simpleTag) {
                out.printin(tagHandlerVar);
                out.print(".setParent(");
                if (parent != null) {
                    if (isSimpleTagParent) {
                        out.print("new javax.servlet.jsp.tagext.TagAdapter(");
                        out.print("(javax.servlet.jsp.tagext.SimpleTag) ");
                        out.print(parent);
                        out.println("));");
                    } else {
                        out.print("(javax.servlet.jsp.tagext.Tag) ");
                        out.print(parent);
                        out.println(");");
                    }
                } else {
                    out.println("null);");
                }
            } else {
                // The setParent() method need not be called if the value being
                // passed is null, since SimpleTag instances are not reused
                if (parent != null) {
                    out.printin(tagHandlerVar);
                    out.print(".setParent(");
                    out.print(parent);
                    out.println(");");
                }
            }

            Node.JspAttribute[] attrs = n.getJspAttributes();
            for (int i = 0; attrs != null && i < attrs.length; i++) {
                String attrValue =
                    evaluateAttribute(handlerInfo, attrs[i], n, tagHandlerVar);

                if (attrs[i].isDynamic()) {
                    out.printin(tagHandlerVar);
                    out.print(".");
                    out.print("setDynamicAttribute(");
                    String uri = attrs[i].getURI();
                    if ("".equals(uri) || (uri == null)) {
                        out.print("null");
                    } else {
                        out.print("\"" + attrs[i].getURI() + "\"");
                    }
                    out.print(", \"");
                    out.print(attrs[i].getLocalName());
                    out.print("\", ");
                    out.print(attrValue);
                    out.println(");");
                } else {
                    out.printin(tagHandlerVar);
                    out.print(".");
                    out.print(
                        handlerInfo
                            .getSetterMethod(attrs[i].getLocalName())
                            .getName());
                    out.print("(");
                    out.print(attrValue);
                    out.println(");");
                }
            }
        }

        /*
         * @param c The target class to which to coerce the given string
         * @param s The string value
         * @param attrName The name of the attribute whose value is being
         * supplied
         * @param propEditorClass The property editor for the given attribute
         * @param isNamedAttribute true if the given attribute is a named
         * attribute (that is, specified using the jsp:attribute standard
         * action), and false otherwise
         */
        private String convertString(
            Class c,
            String s,
            String attrName,
            Class propEditorClass,
            boolean isNamedAttribute)
            throws JasperException {

            String quoted = s;
            if (!isNamedAttribute) {
                quoted = quote(s);
            }

            if (propEditorClass != null) {
                String className = JspUtil.getCanonicalName(c);
                return "("
                    + className
                    + ")org.apache.jasper.runtime.JspRuntimeLibrary.getValueFromBeanInfoPropertyEditor("
                    + className
                    + ".class, \""
                    + attrName
                    + "\", "
                    + quoted
                    + ", "
                    + JspUtil.getCanonicalName(propEditorClass)
                    + ".class)";
            } else if (c == String.class) {
                return quoted;
            } else if (c == boolean.class) {
                return JspUtil.coerceToPrimitiveBoolean(s, isNamedAttribute);
            } else if (c == Boolean.class) {
                return JspUtil.coerceToBoolean(s, isNamedAttribute);
            } else if (c == byte.class) {
                return JspUtil.coerceToPrimitiveByte(s, isNamedAttribute);
            } else if (c == Byte.class) {
                return JspUtil.coerceToByte(s, isNamedAttribute);
            } else if (c == char.class) {
                return JspUtil.coerceToChar(s, isNamedAttribute);
            } else if (c == Character.class) {
                return JspUtil.coerceToCharacter(s, isNamedAttribute);
            } else if (c == double.class) {
                return JspUtil.coerceToPrimitiveDouble(s, isNamedAttribute);
            } else if (c == Double.class) {
                return JspUtil.coerceToDouble(s, isNamedAttribute);
            } else if (c == float.class) {
                return JspUtil.coerceToPrimitiveFloat(s, isNamedAttribute);
            } else if (c == Float.class) {
                return JspUtil.coerceToFloat(s, isNamedAttribute);
            } else if (c == int.class) {
                return JspUtil.coerceToInt(s, isNamedAttribute);
            } else if (c == Integer.class) {
                return JspUtil.coerceToInteger(s, isNamedAttribute);
            } else if (c == short.class) {
                return JspUtil.coerceToPrimitiveShort(s, isNamedAttribute);
            } else if (c == Short.class) {
                return JspUtil.coerceToShort(s, isNamedAttribute);
            } else if (c == long.class) {
                return JspUtil.coerceToPrimitiveLong(s, isNamedAttribute);
            } else if (c == Long.class) {
                return JspUtil.coerceToLong(s, isNamedAttribute);
            } else if (c == Object.class) {
                return "new String(" + quoted + ")";
            } else {
                String className = JspUtil.getCanonicalName(c);
                return "("
                    + className
                    + ")org.apache.jasper.runtime.JspRuntimeLibrary.getValueFromPropertyEditorManager("
                    + className
                    + ".class, \""
                    + attrName
                    + "\", "
                    + quoted
                    + ")";
            }
        }

        /*
         * Converts the scope string representation, whose possible values
         * are "page", "request", "session", and "application", to the
         * corresponding scope constant.
         */
        private String getScopeConstant(String scope) {
            String scopeName = "PageContext.PAGE_SCOPE"; // Default to page

            if ("request".equals(scope)) {
                scopeName = "PageContext.REQUEST_SCOPE";
            } else if ("session".equals(scope)) {
                scopeName = "PageContext.SESSION_SCOPE";
            } else if ("application".equals(scope)) {
                scopeName = "PageContext.APPLICATION_SCOPE";
            }

            return scopeName;
        }

        /**
         * Generates anonymous JspFragment inner class which is passed as an
         * argument to SimpleTag.setJspBody().
         */
        private void generateJspFragment(Node n, String tagHandlerVar)
            throws JasperException {
            // XXX - A possible optimization here would be to check to see
            // if the only child of the parent node is TemplateText.  If so,
            // we know there won't be any parameters, etc, so we can 
            // generate a low-overhead JspFragment that just echoes its
            // body.  The implementation of this fragment can come from
            // the org.apache.jasper.runtime package as a support class.
            FragmentHelperClass.Fragment fragment =
                fragmentHelperClass.openFragment(
                    n,
                    tagHandlerVar,
                    methodNesting);
            ServletWriter outSave = out;
            out = fragment.getGenBuffer().getOut();
            String tmpParent = parent;
            parent = "_jspx_parent";
            boolean isSimpleTagParentSave = isSimpleTagParent;
            isSimpleTagParent = true;
            boolean tmpIsFragment = isFragment;
            isFragment = true;
            String pushBodyCountVarSave = pushBodyCountVar;
            if (pushBodyCountVar != null) {
                // Use a fixed name for push body count, to simplify code gen
                pushBodyCountVar = "_jspx_push_body_count";
            }
            visitBody(n);
            out = outSave;
            parent = tmpParent;
            isSimpleTagParent = isSimpleTagParentSave;
            isFragment = tmpIsFragment;
            pushBodyCountVar = pushBodyCountVarSave;
            fragmentHelperClass.closeFragment(fragment, methodNesting);
            // XXX - Need to change pageContext to jspContext if
            // we're not in a place where pageContext is defined (e.g.
            // in a fragment or in a tag file.
            out.print(
                "new "
                    + fragmentHelperClass.getClassName()
                    + "( "
                    + fragment.getId()
                    + ", _jspx_page_context, "
                    + tagHandlerVar
                    + ", "
                    + pushBodyCountVar
                    + ")");
        }

        /**
         * Generate the code required to obtain the runtime value of the
         * given named attribute.
         *
         * @return The name of the temporary variable the result is stored in.
         */
        public String generateNamedAttributeValue(Node.NamedAttribute n)
            throws JasperException {

            String varName = n.getTemporaryVariableName();

            // If the only body element for this named attribute node is
            // template text, we need not generate an extra call to
            // pushBody and popBody.  Maybe we can further optimize
            // here by getting rid of the temporary variable, but in
            // reality it looks like javac does this for us.
            Node.Nodes body = n.getBody();
            if (body != null) {
                boolean templateTextOptimization = false;
                if (body.size() == 1) {
                    Node bodyElement = body.getNode(0);
                    if (bodyElement instanceof Node.TemplateText) {
                        templateTextOptimization = true;
                        out.printil(
                            "String "
                                + varName
                                + " = "
                                + quote(
                                    new String(
                                        ((Node.TemplateText)bodyElement)
                                            .getText()))
                                + ";");
                    }
                }

                // XXX - Another possible optimization would be for
                // lone EL expressions (no need to pushBody here either).

                if (!templateTextOptimization) {
                    out.printil("out = _jspx_page_context.pushBody();");
                    visitBody(n);
                    out.printil(
                        "String "
                            + varName
                            + " = "
                            + "((javax.servlet.jsp.tagext.BodyContent)"
                            + "out).getString();");
                    out.printil("out = _jspx_page_context.popBody();");
                }
            } else {
                // Empty body must be treated as ""
                out.printil("String " + varName + " = \"\";");
            }

            return varName;
        }

        /**
         * Similar to generateNamedAttributeValue, but create a JspFragment
         * instead.
         *
         * @param n The parent node of the named attribute
         * @param tagHandlerVar The variable the tag handler is stored in,
         *     so the fragment knows its parent tag.
         * @return The name of the temporary variable the fragment 
         *     is stored in.
         */
        public String generateNamedAttributeJspFragment(
            Node.NamedAttribute n,
            String tagHandlerVar)
            throws JasperException {
            String varName = n.getTemporaryVariableName();

            out.printin(
                "javax.servlet.jsp.tagext.JspFragment " + varName + " = ");
            generateJspFragment(n, tagHandlerVar);
            out.println(";");

            return varName;
        }
    }

    private static void generateLocalVariables(ServletWriter out, Node n)
        throws JasperException {
        Node.ChildInfo ci;
        if (n instanceof Node.CustomTag) {
            ci = ((Node.CustomTag)n).getChildInfo();
        } else if (n instanceof Node.JspBody) {
            ci = ((Node.JspBody)n).getChildInfo();
        } else if (n instanceof Node.NamedAttribute) {
            ci = ((Node.NamedAttribute)n).getChildInfo();
        } else {
            // Cannot access err since this method is static, but at
            // least flag an error.
            throw new JasperException("Unexpected Node Type");
            //err.getString( 
            //    "jsp.error.internal.unexpected_node_type" ) );
        }

        if (ci.hasUseBean()) {
            out.printil("HttpSession session = _jspx_page_context.getSession();");
            out.printil(
                "ServletContext application = _jspx_page_context.getServletContext();");
        }
        if (ci.hasUseBean()
            || ci.hasIncludeAction()
            || ci.hasSetProperty()
            || ci.hasParamAction()) {
            out.printil(
                "HttpServletRequest request = (HttpServletRequest)_jspx_page_context.getRequest();");
        }
        if (ci.hasIncludeAction()) {
            out.printil(
                "HttpServletResponse response = (HttpServletResponse)_jspx_page_context.getResponse();");
        }
    }

    /**
     * Common part of postamble, shared by both servlets and tag files.
     */
    private void genCommonPostamble() {
        // Append any methods that were generated in the buffer.
        for (int i = 0; i < methodsBuffered.size(); i++) {
            GenBuffer methodBuffer = (GenBuffer)methodsBuffered.get(i);
            methodBuffer.adjustJavaLines(out.getJavaLine() - 1);
            out.printMultiLn(methodBuffer.toString());
        }

        // Append the helper class
        if (fragmentHelperClass.isUsed()) {
            fragmentHelperClass.generatePostamble();
            fragmentHelperClass.adjustJavaLines(out.getJavaLine() - 1);
            out.printMultiLn(fragmentHelperClass.toString());
        }

        // Append char array declarations
        if (charArrayBuffer != null) {
            out.printMultiLn(charArrayBuffer.toString());
        }

        // Close the class definition
        out.popIndent();
        out.printil("}");
    }

    /**
     * Generates the ending part of the static portion of the servlet.
     */
    private void generatePostamble(Node.Nodes page) {
        out.popIndent();
        out.printil("} catch (Throwable t) {");
        out.pushIndent();
        out.printil(
            "if (!(t instanceof SkipPageException)){");
        out.pushIndent();
        out.printil("out = _jspx_out;");
        out.printil("if (out != null && out.getBufferSize() != 0)");
        out.pushIndent();
        out.printil("out.clearBuffer();");
        out.popIndent();

        out.printil(
            "if (_jspx_page_context != null) _jspx_page_context.handlePageException(t);");
        out.popIndent();
        out.printil("}");
        out.popIndent();
        out.printil("} finally {");
        out.pushIndent();

        out.printil(
            "if (_jspxFactory != null) _jspxFactory.releasePageContext(_jspx_page_context);");

        out.popIndent();
        out.printil("}");

        // Close the service method
        out.popIndent();
        out.printil("}");

        // Generated methods, helper classes, etc.
        genCommonPostamble();
    }

    /**
     * Constructor.
     */
    Generator(ServletWriter out, Compiler compiler) {
        this.out = out;
        methodsBuffered = new ArrayList();
        charArrayBuffer = null;
        err = compiler.getErrorDispatcher();
        ctxt = compiler.getCompilationContext();
        fragmentHelperClass =
            new FragmentHelperClass(ctxt.getServletClassName() + "Helper");
        pageInfo = compiler.getPageInfo();

        /*
         * Temporary hack. If a JSP page uses the "extends" attribute of the
         * page directive, the _jspInit() method of the generated servlet class
         * will not be called (it is only called for those generated servlets
         * that extend HttpJspBase, the default), causing the tag handler pools
         * not to be initialized and resulting in a NPE.
         * The JSP spec needs to clarify whether containers can override
         * init() and destroy(). For now, we just disable tag pooling for pages
         * that use "extends".
         */
        if (pageInfo.getExtends(false) == null) {
            isPoolingEnabled = ctxt.getOptions().isPoolingEnabled();
        } else {
            isPoolingEnabled = false;
        }
        beanInfo = pageInfo.getBeanRepository();
        breakAtLF = ctxt.getOptions().getMappedFile();
        if (isPoolingEnabled) {
            tagHandlerPoolNames = new Vector();
        }
    }

    /**
     * The main entry for Generator.
     * @param out The servlet output writer
     * @param compiler The compiler
     * @param page The input page
     */
    public static void generate(
        ServletWriter out,
        Compiler compiler,
        Node.Nodes page)
        throws JasperException {

        Generator gen = new Generator(out, compiler);

        if (gen.isPoolingEnabled) {
            gen.compileTagHandlerPoolList(page);
        }
        if (gen.ctxt.isTagFile()) {
            JasperTagInfo tagInfo = (JasperTagInfo)gen.ctxt.getTagInfo();
            gen.generateTagHandlerPreamble(tagInfo, page);

            if (gen.ctxt.isPrototypeMode()) {
                return;
            }

            gen.generateXmlProlog(page);
            gen.fragmentHelperClass.generatePreamble();
            page.visit(
                gen.new GenerateVisitor(
                    gen.ctxt.isTagFile(),
                    out,
                    gen.methodsBuffered,
                    gen.fragmentHelperClass,
                    gen.ctxt.getClassLoader(),
                    tagInfo));
            gen.generateTagHandlerPostamble(tagInfo);
        } else {
            gen.generatePreamble(page);
            gen.generateXmlProlog(page);
            gen.fragmentHelperClass.generatePreamble();
            page.visit(
                gen.new GenerateVisitor(
                    gen.ctxt.isTagFile(),
                    out,
                    gen.methodsBuffered,
                    gen.fragmentHelperClass,
                    gen.ctxt.getClassLoader(),
                    null));
            gen.generatePostamble(page);
        }
    }

    /*
     * Generates tag handler preamble.
     */
    private void generateTagHandlerPreamble(
        JasperTagInfo tagInfo,
        Node.Nodes tag)
        throws JasperException {

        // Generate package declaration
        String className = tagInfo.getTagClassName();
        int lastIndex = className.lastIndexOf('.');
        if (lastIndex != -1) {
            String pkgName = className.substring(0, lastIndex);
            genPreamblePackage(pkgName);
            className = className.substring(lastIndex + 1);
        }

        // Generate imports
        genPreambleImports();

        // Generate class declaration
        out.printin("public final class ");
        out.println(className);
        out.printil("    extends javax.servlet.jsp.tagext.SimpleTagSupport");
        out.printin(
            "    implements org.apache.jasper.runtime.JspSourceDependent");
        if (tagInfo.hasDynamicAttributes()) {
            out.println(",");
            out.printin(
                "               javax.servlet.jsp.tagext.DynamicAttributes");
        }
        out.println(" {");
        out.println();
        out.pushIndent();

        /*
         * Class body begins here
         */

        generateDeclarations(tag);

        // Static initializations here
        genPreambleStaticInitializers();

        out.printil("private JspContext jspContext;");

        // Declare writer used for storing result of fragment/body invocation
        // if 'varReader' or 'var' attribute is specified
        out.printil("private java.io.Writer _jspx_sout;");

        // Class variable declarations
        genPreambleClassVariableDeclarations(tagInfo.getTagName());

        generateSetJspContext(tagInfo);

        // Tag-handler specific declarations
        generateTagHandlerAttributes(tagInfo);
        if (tagInfo.hasDynamicAttributes())
            generateSetDynamicAttribute();

        // Methods here
        genPreambleMethods();

        // Now the doTag() method
        out.printil(
            "public void doTag() throws JspException, java.io.IOException {");

        if (ctxt.isPrototypeMode()) {
            out.printil("}");
            out.popIndent();
            out.printil("}");
            return;
        }

        out.pushIndent();

        /*
         * According to the spec, 'pageContext' must not be made available as
         * an implicit object in tag files.
         * Declare _jspx_page_context, so we can share the code generator with
         * JSPs. 
         */
        out.printil("PageContext _jspx_page_context = (PageContext)jspContext;");

        // Declare implicit objects.  
        out.printil(
            "HttpServletRequest request = "
                + "(HttpServletRequest) _jspx_page_context.getRequest();");
        out.printil(
            "HttpServletResponse response = "
                + "(HttpServletResponse) _jspx_page_context.getResponse();");
        out.printil("HttpSession session = _jspx_page_context.getSession();");
        out.printil(
            "ServletContext application = _jspx_page_context.getServletContext();");
        out.printil("ServletConfig config = _jspx_page_context.getServletConfig();");
        out.printil("JspWriter out = jspContext.getOut();");
        if (isPoolingEnabled && !tagHandlerPoolNames.isEmpty()) {
            out.printil("_jspInit(config);");
        }
        generatePageScopedVariables(tagInfo);

        // Number of tag object that need to be popped
        // XXX TODO: use a better criteria
        maxTagNesting = pageInfo.getMaxTagNesting();

        declareTemporaryScriptingVars(tag);
        out.println();

        out.printil("try {");
        out.pushIndent();
    }

    private void generateTagHandlerPostamble(TagInfo tagInfo) {
        out.popIndent();

        // Have to catch Throwable because a classic tag handler
        // helper method is declared to throw Throwable.
        out.printil("} catch( Throwable t ) {");
        out.pushIndent();
        out.printil("if( t instanceof SkipPageException )");
        out.printil("    throw (SkipPageException) t;");
        out.printil("if( t instanceof java.io.IOException )");
        out.printil("    throw (java.io.IOException) t;");
        out.printil("if( t instanceof IllegalStateException )");
        out.printil("    throw (IllegalStateException) t;");
        out.printil("if( t instanceof JspException )");
        out.printil("    throw (JspException) t;");
        out.printil("throw new JspException(t);");
        out.popIndent();
        out.printil("} finally {");
        out.pushIndent();
        out.printil(
            "((org.apache.jasper.runtime.JspContextWrapper) jspContext).syncEndTagFile();");
        if (isPoolingEnabled && !tagHandlerPoolNames.isEmpty()) {
            out.printil("_jspDestroy();");
        }
        out.popIndent();
        out.printil("}");

        // Close the doTag method
        out.popIndent();
        out.printil("}");

        // Generated methods, helper classes, etc.
        genCommonPostamble();
    }

    /**
     * Generates declarations for tag handler attributes, and defines the
     * getter and setter methods for each.
     */
    private void generateTagHandlerAttributes(TagInfo tagInfo)
        throws JasperException {

        if (tagInfo.hasDynamicAttributes()) {
            out.printil(
                "private java.util.HashMap _jspx_dynamic_attrs = new java.util.HashMap();");
        }

        // Declare attributes
        TagAttributeInfo[] attrInfos = tagInfo.getAttributes();
        for (int i = 0; i < attrInfos.length; i++) {
            out.printin("private ");
            if (attrInfos[i].isFragment()) {
                out.print("javax.servlet.jsp.tagext.JspFragment ");
            } else {
                out.print(attrInfos[i].getTypeName());
                out.print(" ");
            }
            out.print(attrInfos[i].getName());
            out.println(";");
        }
        out.println();

        // Define attribute getter and setter methods
        if (attrInfos != null) {
            for (int i = 0; i < attrInfos.length; i++) {
                // getter method
                out.printin("public ");
                if (attrInfos[i].isFragment()) {
                    out.print("javax.servlet.jsp.tagext.JspFragment ");
                } else {
                    out.print(attrInfos[i].getTypeName());
                    out.print(" ");
                }
                out.print(toGetterMethod(attrInfos[i].getName()));
                out.println(" {");
                out.pushIndent();
                out.printin("return this.");
                out.print(attrInfos[i].getName());
                out.println(";");
                out.popIndent();
                out.printil("}");
                out.println();

                // setter method
                out.printin("public void ");
                out.print(toSetterMethodName(attrInfos[i].getName()));
                if (attrInfos[i].isFragment()) {
                    out.print("(javax.servlet.jsp.tagext.JspFragment ");
                } else {
                    out.print("(");
                    out.print(attrInfos[i].getTypeName());
                    out.print(" ");
                }
                out.print(attrInfos[i].getName());
                out.println(") {");
                out.pushIndent();
                out.printin("this.");
                out.print(attrInfos[i].getName());
                out.print(" = ");
                out.print(attrInfos[i].getName());
                out.println(";");
                out.popIndent();
                out.printil("}");
                out.println();
            }
        }
    }

    /*
     * Generate setter for JspContext so we can create a wrapper and
     * store both the original and the wrapper.  We need the wrapper
     * to mask the page context from the tag file and simulate a 
     * fresh page context.  We need the original to do things like
     * sync AT_BEGIN and AT_END scripting variables.
     */
    private void generateSetJspContext(TagInfo tagInfo) {

        boolean nestedSeen = false;
        boolean atBeginSeen = false;
        boolean atEndSeen = false;

        // Determine if there are any aliases
        boolean aliasSeen = false;
        TagVariableInfo[] tagVars = tagInfo.getTagVariableInfos();
        for (int i = 0; i < tagVars.length; i++) {
            if (tagVars[i].getNameFromAttribute() != null
                && tagVars[i].getNameGiven() != null) {
                aliasSeen = true;
                break;
            }
        }

        if (aliasSeen) {
            out.printil(
                "public void setJspContext(JspContext ctx, java.util.Map aliasMap) {");
        } else {
            out.printil("public void setJspContext(JspContext ctx) {");
        }
        out.pushIndent();
        out.printil("super.setJspContext(ctx);");
        out.printil("java.util.ArrayList _jspx_nested = null;");
        out.printil("java.util.ArrayList _jspx_at_begin = null;");
        out.printil("java.util.ArrayList _jspx_at_end = null;");

        for (int i = 0; i < tagVars.length; i++) {

            switch (tagVars[i].getScope()) {
                case VariableInfo.NESTED :
                    if (!nestedSeen) {
                        out.printil(
                            "_jspx_nested = new java.util.ArrayList();");
                        nestedSeen = true;
                    }
                    out.printin("_jspx_nested.add(");
                    break;

                case VariableInfo.AT_BEGIN :
                    if (!atBeginSeen) {
                        out.printil(
                            "_jspx_at_begin = new java.util.ArrayList();");
                        atBeginSeen = true;
                    }
                    out.printin("_jspx_at_begin.add(");
                    break;

                case VariableInfo.AT_END :
                    if (!atEndSeen) {
                        out.printil(
                            "_jspx_at_end = new java.util.ArrayList();");
                        atEndSeen = true;
                    }
                    out.printin("_jspx_at_end.add(");
                    break;
            } // switch

            out.print(quote(tagVars[i].getNameGiven()));
            out.println(");");
        }
        if (aliasSeen) {
            out.printil(
                "this.jspContext = new org.apache.jasper.runtime.JspContextWrapper(ctx, _jspx_nested, _jspx_at_begin, _jspx_at_end, aliasMap);");
        } else {
            out.printil(
                "this.jspContext = new org.apache.jasper.runtime.JspContextWrapper(ctx, _jspx_nested, _jspx_at_begin, _jspx_at_end, null);");
        }
        out.popIndent();
        out.printil("}");
        out.println();
        out.printil("public JspContext getJspContext() {");
        out.pushIndent();
        out.printil("return this.jspContext;");
        out.popIndent();
        out.printil("}");
    }

    /*
     * Generates implementation of
     * javax.servlet.jsp.tagext.DynamicAttributes.setDynamicAttribute() method,
     * which saves each dynamic attribute that is passed in so that a scoped
     * variable can later be created for it.
     */
    public void generateSetDynamicAttribute() {
        out.printil(
            "public void setDynamicAttribute(String uri, String localName, Object value) throws JspException {");
        out.pushIndent();
        /* 
         * According to the spec, only dynamic attributes with no uri are to
         * be present in the Map; all other dynamic attributes are ignored.
         */
        out.printil("if (uri == null)");
        out.pushIndent();
        out.printil("_jspx_dynamic_attrs.put(localName, value);");
        out.popIndent();
        out.popIndent();
        out.printil("}");
    }

    /*
     * Creates a page-scoped variable for each declared tag attribute.
     * Also, if the tag accepts dynamic attributes, a page-scoped variable
     * is made available for each dynamic attribute that was passed in.
     */
    private void generatePageScopedVariables(JasperTagInfo tagInfo) {

        // "normal" attributes
        TagAttributeInfo[] attrInfos = tagInfo.getAttributes();
        for (int i = 0; i < attrInfos.length; i++) {
            String attrName = attrInfos[i].getName();
            out.printil("if( " + toGetterMethod(attrName) + " != null ) ");
            out.pushIndent();
            out.printin("_jspx_page_context.setAttribute(");
            out.print(quote(attrName));
            out.print(", ");
            out.print(toGetterMethod(attrName));
            out.println(");");
            out.popIndent();
        }

        // Expose the Map containing dynamic attributes as a page-scoped var
        if (tagInfo.hasDynamicAttributes()) {
            out.printin("_jspx_page_context.setAttribute(\"");
            out.print(tagInfo.getDynamicAttributesMapName());
            out.print("\", _jspx_dynamic_attrs);");
        }
    }

    /*
     * Generates the getter method for the given attribute name.
     */
    private String toGetterMethod(String attrName) {
        char[] attrChars = attrName.toCharArray();
        attrChars[0] = Character.toUpperCase(attrChars[0]);
        return "get" + new String(attrChars) + "()";
    }

    /*
     * Generates the setter method name for the given attribute name.
     */
    private String toSetterMethodName(String attrName) {
        char[] attrChars = attrName.toCharArray();
        attrChars[0] = Character.toUpperCase(attrChars[0]);
        return "set" + new String(attrChars);
    }

    /**
     * Class storing the result of introspecting a custom tag handler.
     */
    private static class TagHandlerInfo {

        private Hashtable methodMaps;
        private Hashtable propertyEditorMaps;
        private Class tagHandlerClass;

        /**
         * Constructor.
         *
         * @param n The custom tag whose tag handler class is to be
         * introspected
         * @param tagHandlerClass Tag handler class
         * @param err Error dispatcher
         */
        TagHandlerInfo(Node n, Class tagHandlerClass, ErrorDispatcher err)
            throws JasperException {
            this.tagHandlerClass = tagHandlerClass;
            this.methodMaps = new Hashtable();
            this.propertyEditorMaps = new Hashtable();

            try {
                BeanInfo tagClassInfo =
                    Introspector.getBeanInfo(tagHandlerClass);
                PropertyDescriptor[] pd = tagClassInfo.getPropertyDescriptors();
                for (int i = 0; i < pd.length; i++) {
                    /*
                     * FIXME: should probably be checking for things like
                     *        pageContext, bodyContent, and parent here -akv
                     */
                    if (pd[i].getWriteMethod() != null) {
                        methodMaps.put(pd[i].getName(), pd[i].getWriteMethod());
                    }
                    if (pd[i].getPropertyEditorClass() != null)
                        propertyEditorMaps.put(
                            pd[i].getName(),
                            pd[i].getPropertyEditorClass());
                }
            } catch (IntrospectionException ie) {
                err.jspError(
                    n,
                    "jsp.error.introspect.taghandler",
                    tagHandlerClass.getName(),
                    ie);
            }
        }

        /**
         * XXX
         */
        public Method getSetterMethod(String attrName) {
            return (Method)methodMaps.get(attrName);
        }

        /**
         * XXX
         */
        public Class getPropertyEditorClass(String attrName) {
            return (Class)propertyEditorMaps.get(attrName);
        }

        /**
         * XXX
         */
        public Class getTagHandlerClass() {
            return tagHandlerClass;
        }
    }

    /**
     * A class for generating codes to a buffer.  Included here are some
     * support for tracking source to Java lines mapping.
     */
    private static class GenBuffer {

        /*
         * For a CustomTag, the codes that are generated at the beginning of
         * the tag may not be in the same buffer as those for the body of the
         * tag.  Two fields are used here to keep this straight.  For codes
         * that do not corresponds to any JSP lines, they should be null.  
         */
        private Node node;
        private Node.Nodes body;
        private java.io.CharArrayWriter charWriter;
        protected ServletWriter out;

        GenBuffer() {
            this(null, null);
        }

        GenBuffer(Node n, Node.Nodes b) {
            node = n;
            body = b;
            if (body != null) {
                body.setGeneratedInBuffer(true);
            }
            charWriter = new java.io.CharArrayWriter();
            out = new ServletWriter(new java.io.PrintWriter(charWriter));
        }

        public ServletWriter getOut() {
            return out;
        }

        public String toString() {
            return charWriter.toString();
        }

        /**
         * Adjust the Java Lines.  This is necessary because the Java lines
         * stored with the nodes are relative the beginning of this buffer
         * and need to be adjusted when this buffer is inserted into the
         * source.
         */
        public void adjustJavaLines(final int offset) {

            if (node != null) {
                adjustJavaLine(node, offset);
            }

            if (body != null) {
                try {
                    body.visit(new Node.Visitor() {

                        public void doVisit(Node n) {
                            adjustJavaLine(n, offset);
                        }

                        public void visit(Node.CustomTag n)
                            throws JasperException {
                            Node.Nodes b = n.getBody();
                            if (b != null && !b.isGeneratedInBuffer()) {
                                // Don't adjust lines for the nested tags that
                                // are also generated in buffers, because the
                                // adjustments will be done elsewhere.
                                b.visit(this);
                            }
                        }
                    });
                } catch (JasperException ex) {
                }
            }
        }

        private static void adjustJavaLine(Node n, int offset) {
            if (n.getBeginJavaLine() > 0) {
                n.setBeginJavaLine(n.getBeginJavaLine() + offset);
                n.setEndJavaLine(n.getEndJavaLine() + offset);
            }
        }
    }

    /**
     * Keeps track of the generated Fragment Helper Class
     */
    private static class FragmentHelperClass {

        private static class Fragment {
            private GenBuffer genBuffer;
            private int id;

            public Fragment(int id, Node node) {
                this.id = id;
                genBuffer = new GenBuffer(null, node.getBody());
            }

            public GenBuffer getGenBuffer() {
                return this.genBuffer;
            }

            public int getId() {
                return this.id;
            }
        }

        // True if the helper class should be generated.
        private boolean used = false;

        private ArrayList fragments = new ArrayList();

        private String className;

        // Buffer for entire helper class
        private GenBuffer classBuffer = new GenBuffer();

        public FragmentHelperClass(String className) {
            this.className = className;
        }

        public String getClassName() {
            return this.className;
        }

        public boolean isUsed() {
            return this.used;
        }

        public void generatePreamble() {
            ServletWriter out = this.classBuffer.getOut();
            out.println();
            out.pushIndent();
            // Note: cannot be static, as we need to reference things like
            // _jspx_meth_*
            out.printil("private class " + className);
            out.printil(
                "    extends " + "org.apache.jasper.runtime.JspFragmentHelper");
            out.printil("{");
            out.pushIndent();
            out.printil(
                "private javax.servlet.jsp.tagext.JspTag _jspx_parent;");
            out.printil("private int[] _jspx_push_body_count;");
            out.println();
            out.printil(
                "public "
                    + className
                    + "( int discriminator, JspContext jspContext, "
                    + "javax.servlet.jsp.tagext.JspTag _jspx_parent, "
                    + "int[] _jspx_push_body_count ) {");
            out.pushIndent();
            out.printil("super( discriminator, jspContext, _jspx_parent );");
            out.printil("this._jspx_parent = _jspx_parent;");
            out.printil("this._jspx_push_body_count = _jspx_push_body_count;");
            out.popIndent();
            out.printil("}");
        }

        public Fragment openFragment(
            Node parent,
            String tagHandlerVar,
            int methodNesting)
            throws JasperException {
            Fragment result = new Fragment(fragments.size(), parent);
            fragments.add(result);
            this.used = true;

            ServletWriter out = result.getGenBuffer().getOut();
            out.pushIndent();
            out.pushIndent();
            // XXX - Returns boolean because if a tag is invoked from
            // within this fragment, the Generator sometimes might
            // generate code like "return true".  This is ignored for now,
            // meaning only the fragment is skipped.  The JSR-152
            // expert group is currently discussing what to do in this case.
            // See comment in closeFragment()
            if (methodNesting > 0) {
                out.printin("public boolean invoke");
            } else {
                out.printin("public void invoke");
            }
            out.println(result.getId() + "( " + "JspWriter out ) ");
            out.pushIndent();
            // Note: Throwable required because methods like _jspx_meth_*
            // throw Throwable.
            out.printil("throws Throwable");
            out.popIndent();
            out.printil("{");
            out.pushIndent();
            generateLocalVariables(out, parent);

            return result;
        }

        public void closeFragment(Fragment fragment, int methodNesting) {
            ServletWriter out = fragment.getGenBuffer().getOut();
            // XXX - See comment in openFragment()
            if (methodNesting > 0) {
                out.printil("return false;");
            } else {
                out.printil("return;");
            }
            out.popIndent();
            out.printil("}");
        }

        public void generatePostamble() {
            ServletWriter out = this.classBuffer.getOut();
            // Generate all fragment methods:
            for (int i = 0; i < fragments.size(); i++) {
                Fragment fragment = (Fragment)fragments.get(i);
                fragment.getGenBuffer().adjustJavaLines(out.getJavaLine() - 1);
                out.printMultiLn(fragment.getGenBuffer().toString());
            }

            // Generate postamble:
            out.printil("public void invoke( java.io.Writer writer )");
            out.pushIndent();
            out.printil("throws JspException");
            out.popIndent();
            out.printil("{");
            out.pushIndent();
            out.printil("JspWriter out = null;");
            out.printil("if( writer != null ) {");
            out.pushIndent();
            out.printil("out = this.jspContext.pushBody(writer);");
            out.popIndent();
            out.printil("} else {");
            out.pushIndent();
            out.printil("out = this.jspContext.getOut();");
            out.popIndent();
            out.printil("}");
            out.printil("try {");
            out.pushIndent();
            out.printil("switch( this.discriminator ) {");
            out.pushIndent();
            for (int i = 0; i < fragments.size(); i++) {
                out.printil("case " + i + ":");
                out.pushIndent();
                out.printil("invoke" + i + "( out );");
                out.printil("break;");
                out.popIndent();
            }
            out.popIndent();
            out.printil("}"); // switch
            out.popIndent();
            out.printil("}"); // try
            out.printil("catch( Throwable e ) {");
            out.pushIndent();
            out.printil(
                "if (e instanceof SkipPageException)");
            out.printil("    throw (SkipPageException) e;");
            out.printil("throw new JspException( e );");
            out.popIndent();
            out.printil("}"); // catch
            out.printil("finally {");
            out.pushIndent();

            out.printil("if( writer != null ) {");
            out.pushIndent();
            out.printil("this.jspContext.popBody();");
            out.popIndent();
            out.printil("}");

            out.popIndent();
            out.printil("}"); // finally
            out.popIndent();
            out.printil("}"); // invoke method
            out.popIndent();
            out.printil("}"); // helper class
            out.popIndent();
        }

        public String toString() {
            return classBuffer.toString();
        }

        public void adjustJavaLines(int offset) {
            for (int i = 0; i < fragments.size(); i++) {
                Fragment fragment = (Fragment)fragments.get(i);
                fragment.getGenBuffer().adjustJavaLines(offset);
            }
        }
    }
}
