Class RegexUtil
java.lang.Object
org.checkerframework.checker.regex.util.RegexUtil
Utility methods for regular expressions, most notably for testing whether a string is a regular
expression.
For an example of intended use, see section Testing whether a string is a regular expression in the Checker Framework manual.
Runtime Dependency: If you use this class, you must distribute (or link to)
checker-qual.jar
, along with your binaries. Or, you can copy this class into your own project.
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Nested Class Summary
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Method Summary
Modifier and TypeMethodDescriptionReturns the argument as a@Regex String
if it is a regex, otherwise throws an error.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
everyStringMatchesSomeRegex
(Collection<String> strings, Collection<@Regex String> regexes) Return true if every string is matched by at least one regex.static boolean
isRegex
(char c) Returns true if the argument is a syntactically valid regular expression.static boolean
Returns true if the argument is a syntactically valid regular expression.static boolean
Returns true if the argument is a syntactically valid regular expression with at least the given number of groups.static <@KeyForBottom FROM extends @Nullable @UnknownKeyFor Object,
@KeyForBottom TO extends @Nullable @UnknownKeyFor Object>
List<TO>mapList
(Function<? super @KeyForBottom FROM, ? extends @KeyForBottom TO> f, Iterable<@KeyForBottom FROM> iterable) Applies the function to each element of the given iterable, producing a list of the results.matchesNoRegex
(Collection<String> strings, Collection<@Regex String> regexes) Return the strings that are matched by no regex.matchesSomeRegex
(Collection<String> strings, Collection<@Regex String> regexes) Return the strings such that any one of the regexes matches it.static boolean
noStringMatchesAnyRegex
(Collection<String> strings, Collection<@Regex String> regexes) Return true if no string is matched by any regex.regexError
(String s) Returns null if the argument is a syntactically valid regular expression.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
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.
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Method Details
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isRegex
@Pure @EnsuresQualifierIf(result=true, expression="#1", qualifier=Regex.class) public static boolean isRegex(String s) Returns true if the argument is a syntactically valid regular expression.- Parameters:
s
- string to check for being a regular expression- Returns:
- true iff s is a regular expression
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isRegex
@Pure @EnsuresQualifierIf(result=true, expression="#1", qualifier=Regex.class) public 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.- Parameters:
s
- string to check for being a regular expressiongroups
- number of groups expected- Returns:
- true iff s is a regular expression with
groups
groups
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isRegex
@Pure @EnsuresQualifierIf(result=true, expression="#1", qualifier=Regex.class) public static boolean isRegex(char c) Returns true if the argument is a syntactically valid regular expression.- Parameters:
c
- char to check for being a regular expression- Returns:
- true iff c is a regular expression
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asRegex
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. It should be very rarely needed.- Parameters:
s
- string to check for being a regular expression- Returns:
- its argument
- Throws:
Error
- if argument is not a regex
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asRegex
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. It should be very rarely needed.- Parameters:
s
- string to check for being a regular expressiongroups
- number of groups expected- Returns:
- its argument
- Throws:
Error
- if argument is not a regex
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regexError
Returns null if the argument is a syntactically valid regular expression. Otherwise returns a string describing why the argument is not a regex.- Parameters:
s
- string to check for being a regular expression- Returns:
- null, or a string describing why the argument is not a regex
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regexError
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.- Parameters:
s
- string to check for being a regular expressiongroups
- number of groups expected- Returns:
- null, or a string describing why the argument is not a regex
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regexException
Returns null if the argument is a syntactically valid regular expression. Otherwise returns a PatternSyntaxException describing why the argument is not a regex.- Parameters:
s
- string to check for being a regular expression- Returns:
- null, or a PatternSyntaxException describing why the argument is not a regex
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regexException
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.- Parameters:
s
- string to check for being a regular expressiongroups
- number of groups expected- Returns:
- null, or a PatternSyntaxException describing why the argument is not a regex
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matchesSomeRegex
public static List<String> matchesSomeRegex(Collection<String> strings, Collection<@Regex String> regexes) Return the strings such that any one of the regexes matches it.- Parameters:
strings
- a collection of stringsregexes
- a collection of regular expressions- Returns:
- the strings such that any one of the regexes matches it
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everyStringMatchesSomeRegex
public static boolean everyStringMatchesSomeRegex(Collection<String> strings, Collection<@Regex String> regexes) Return true if every string is matched by at least one regex.- Parameters:
strings
- a collection of stringsregexes
- a collection of regular expressions- Returns:
- true if every string is matched by at least one regex
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matchesNoRegex
public static List<String> matchesNoRegex(Collection<String> strings, Collection<@Regex String> regexes) Return the strings that are matched by no regex.- Parameters:
strings
- a collection of stringsregexes
- a collection of regular expressions- Returns:
- the strings such that none of the regexes matches it
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noStringMatchesAnyRegex
public static boolean noStringMatchesAnyRegex(Collection<String> strings, Collection<@Regex String> regexes) Return true if no string is matched by any regex.- Parameters:
strings
- a collection of stringsregexes
- a collection of regular expressions- Returns:
- true if no string is matched by any regex
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mapList
public static <@KeyForBottom FROM extends @Nullable @UnknownKeyFor Object,@KeyForBottom TO extends @Nullable @UnknownKeyFor Object> List<TO> mapList(Function<? super @KeyForBottom FROM, ? extends @KeyForBottom TO> f, Iterable<@KeyForBottom FROM> iterable) Applies the function to each element of the given iterable, producing a list of the results.The point of this method is to make mapping operations more concise. Import it with
import static org.plumelib.util.CollectionsPlume.mapList;
This method is just liketransform
, but with the arguments in the other order.To perform replacement in place, see
List.replaceAll
.- Type Parameters:
FROM
- the type of elements of the given iterableTO
- the type of elements of the result list- Parameters:
f
- a functioniterable
- an iterable- Returns:
- a list of the results of applying
f
to the elements ofiterable
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