public class RegexUtil extends Object
For an example of intended use, see section Testing whether a string is a regular expression in the Checker Framework manual.
Runtime Dependency: Using this class introduces a runtime dependency. This means that you need to distribute (or link to) the Checker Framework, along with your binaries. To eliminate this dependency, you can simply copy this class into your own project.
Modifier and Type | Class and Description |
---|---|
static class |
RegexUtil.CheckedPatternSyntaxException
A checked version of
PatternSyntaxException . |
Modifier and Type | Method and Description |
---|---|
static @Regex String |
asRegex(String s)
Returns the argument as a
@Regex String if it is a regex,
otherwise throws an error. |
static @Regex String |
asRegex(String s,
int groups)
Returns the argument as a
@Regex(groups) String if it is a regex
with at least the given number of groups, otherwise throws an error. |
static boolean |
isRegex(char c)
Returns true if the argument is a syntactically valid regular
expression.
|
static boolean |
isRegex(String s)
Returns true if the argument is a syntactically valid regular
expression.
|
static boolean |
isRegex(String s,
int groups)
Returns true if the argument is a syntactically valid regular
expression with at least the given number of groups.
|
static @Nullable String |
regexError(String s)
Returns null if the argument is a syntactically valid regular
expression.
|
static @Nullable String |
regexError(String s,
int groups)
Returns null if the argument is a syntactically valid regular
expression with at least the given number of groups.
|
static @Nullable PatternSyntaxException |
regexException(String s)
Returns null if the argument is a syntactically valid regular
expression.
|
static @Nullable PatternSyntaxException |
regexException(String s,
int groups)
Returns null if the argument is a syntactically valid regular
expression with at least the given number of groups.
|
public static boolean isRegex(String s)
s
- string to check for being a regular expression@Pure public static boolean isRegex(String s, int groups)
s
- string to check for being a regular expressiongroups
- number of groups expected@Pure public static boolean isRegex(char c)
c
- char to check for being a regular expression@Pure public static @Nullable String regexError(String s)
s
- string to check for being a regular expression@Pure public static @Nullable String regexError(String s, int groups)
s
- string to check for being a regular expressiongroups
- number of groups expected@Pure public static @Nullable PatternSyntaxException regexException(String s)
s
- string to check for being a regular expression@Pure public static @Nullable PatternSyntaxException regexException(String s, int groups)
s
- string to check for being a regular expressiongroups
- number of groups expectedpublic static @Regex String asRegex(String s)
@Regex String
if it is a regex,
otherwise throws an error. The purpose of this method is to suppress Regex
Checker warnings. Once the the Regex Checker supports flow-sensitivity, it
should be very rarely needed.s
- string to check for being a regular expressionError
- if argument is not a regex@Pure public static @Regex String asRegex(String s, int groups)
@Regex(groups) String
if it is a regex
with at least the given number of groups, otherwise throws an error. The
purpose of this method is to suppress Regex Checker warnings. Once the
Regex Checker supports flow-sensitivity, it should be very rarely needed.s
- string to check for being a regular expressiongroups
- number of groups expectedError
- if argument is not a regex