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The Java Developers Almanac 1.4Order this book from Amazon. |
e6. Getting and Setting a Property of a BeanThis example demonstrates how to get and set the value of a property in a bean usingExpression and Statement . The example gets
and sets three types of properties, an Object , a primitive type,
and an array. Both these classes use the name of the method that gets
or sets the property.
Object o = new MyBean(); try { // Get the value of prop1 Expression expr = new Expression(o, "getProp1", new Object[0]); expr.execute(); String s = (String)expr.getValue(); // Set the value of prop1 Statement stmt = new Statement(o, "setProp1", new Object[]{"new string"}); stmt.execute(); // Get the value of prop2 expr = new Expression(o, "getProp2", new Object[0]); expr.execute(); int i = ((Integer)expr.getValue()).intValue(); // Set the value of prop2 stmt = new Statement(o, "setProp2", new Object[]{new Integer(123)}); stmt.execute(); // Get the value of prop1 expr = new Expression(o, "getProp3", new Object[0]); expr.execute(); byte[] bytes = (byte[])expr.getValue(); // Set the value of prop1 stmt = new Statement(o, "setProp3", new Object[]{new byte[]{0x12, 0x23}}); stmt.execute(); } catch (Exception e) { } public class MyBean { // Property prop1 String prop1; public String getProp1() { return prop1; } public void setProp1(String s) { prop1 = s; } // Property prop2 int prop2; public int getProp2() { return prop2; } public void setProp2(int i) { prop2 = i; } // Property prop3 byte[] prop3; public byte[] getProp3() { return prop3; } public void setProp3(byte[] bytes) { prop3 = bytes; } }
e2. Implementing a Bound Property e3. Implementing a Constrained Property e4. Instantiating a Bean e5. Listing the Property Names of a Bean
© 2002 Addison-Wesley. |