checkers.regex

Class RegexUtil

@NonNull java.lang.Object

checkers.regex.RegexUtil

public class RegexUtil
extends @NonNull Object

Utility methods for regular expressions.

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.

Method Summary

Methods

Modifier and Type	Method and Description
static @ReadOnly String	asRegex(@ReadOnly String s) Returns the argument as a @Regex String if it is a regex, otherwise throws an error.
static @ReadOnly String	asRegex(@ReadOnly 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(@ReadOnly String s) Returns true if the argument is a syntactically valid regular expression.
static boolean	isRegex(@ReadOnly String s, int groups) Returns true if the argument is a syntactically valid regular expression with at least the given number of groups.
static @ReadOnly String	regexError(@ReadOnly String s) Returns null if the argument is a syntactically valid regular expression.
static @ReadOnly String	regexError(@ReadOnly 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(@ReadOnly String s) Returns null if the argument is a syntactically valid regular expression.
static @Nullable PatternSyntaxException	regexException(@ReadOnly String s, int groups) Returns null if the argument is a syntactically valid regular expression with at least the given number of groups.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

isRegex

public static boolean isRegex(@ReadOnly String s)

Returns true if the argument is a syntactically valid regular expression.

isRegex

public static boolean isRegex(@ReadOnly String s,
              int groups)

Returns true if the argument is a syntactically valid regular expression with at least the given number of groups.

isRegex

public static boolean isRegex(char c)

Returns true if the argument is a syntactically valid regular expression.

regexError

public static @ReadOnly String regexError(@ReadOnly String s)

Returns null if the argument is a syntactically valid regular expression. Otherwise returns a string describing why the argument is not a regex.

regexError

public static @ReadOnly String regexError(@ReadOnly String s,
                          int groups)

Returns null if the argument is a syntactically valid regular expression with at least the given number of groups. Otherwise returns a string describing why the argument is not a regex.

regexException

public static @Nullable PatternSyntaxException regexException(@ReadOnly String s)

Returns null if the argument is a syntactically valid regular expression. Otherwise returns a PatternSyntaxException describing why the argument is not a regex.

regexException

public static @Nullable PatternSyntaxException regexException(@ReadOnly String s,
                                              int groups)

Returns null if the argument is a syntactically valid regular expression with at least the given number of groups. Otherwise returns a PatternSyntaxException describing why the argument is not a regex.

asRegex

public static @ReadOnly String asRegex(@ReadOnly String s)

Returns the argument as a @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.

asRegex

public static @ReadOnly String asRegex(@ReadOnly 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. 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.