com.igormaznitsa.jcp.utils.antpathmatcher

Class AntPathMatcher

java.lang.Object

com.igormaznitsa.jcp.utils.antpathmatcher.AntPathMatcher

All Implemented Interfaces:

PathMatcher

public final class AntPathMatcher
extends java.lang.Object
implements PathMatcher

PathMatcher implementation for Ant-style path patterns.

Part of this mapping code has been kindly borrowed from Apache Ant.

The mapping matches URLs using the following rules:

• ? matches one character
• * matches zero or more characters
• ** matches zero or more directories in a path
• {spring:[a-z]+} matches the regexp [a-z]+ as a path variable named "spring"

Examples

• com/t?st.jsp — matches com/test.jsp but also com/tast.jsp or com/txst.jsp
• com/*.jsp — matches all .jsp files in the com directory
• com/**/test.jsp — matches all test.jsp files underneath the com path
• org/springframework/**/*.jsp — matches all .jsp files underneath the org/springframework path
• org/**/servlet/bla.jsp — matches org/springframework/servlet/bla.jsp but also org/springframework/testing/servlet/bla.jsp and org/servlet/bla.jsp
• com/{filename:\\w+}.jsp will match com/test.jsp and assign the value test to the filename variable

Note: a pattern and a path must both be absolute or must both be relative in order for the two to match. Therefore it is recommended that users of this implementation to sanitize patterns in order to prefix them with "/" as it makes sense in the context in which they're used.

Since:

16.07.2003

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	AntPathMatcher.AntPathStringMatcher Tests whether or not a string matches against a pattern via a Pattern.
protected static class	AntPathMatcher.AntPatternComparator The default Comparator implementation returned by getPatternComparator(String).
private static class	AntPathMatcher.PathSeparatorPatternCache A simple cache for patterns that depend on the configured path separator.

Field Summary

Fields

Modifier and Type	Field and Description
private static int	CACHE_TURNOFF_THRESHOLD
private java.lang.Boolean	cachePatterns
private boolean	caseSensitive
static java.lang.String	DEFAULT_PATH_SEPARATOR Default path separator: "/"
private java.lang.String	pathSeparator
private AntPathMatcher.PathSeparatorPatternCache	pathSeparatorPatternCache
(package private) java.util.Map<java.lang.String,AntPathMatcher.AntPathStringMatcher>	stringMatcherCache
private java.util.Map<java.lang.String,java.lang.String[]>	tokenizedPatternCache
private boolean	trimTokens
private static java.util.regex.Pattern	VARIABLE_PATTERN
private static char[]	WILDCARD_CHARS

Constructor Summary

Constructors

Constructor and Description
AntPathMatcher() Create a new instance with the DEFAULT_PATH_SEPARATOR.
AntPathMatcher(java.lang.String pathSeparator) A convenient, alternative constructor to use with a custom path separator.

Method Summary

Modifier and Type	Method and Description
java.lang.String	combine(java.lang.String pattern1, java.lang.String pattern2) Combine two patterns into a new pattern.
private java.lang.String	concat(java.lang.String path1, java.lang.String path2)
private void	deactivatePatternCache()
protected boolean	doMatch(java.lang.String pattern, java.lang.String path, boolean fullMatch, java.util.Map<java.lang.String,java.lang.String> uriTemplateVariables) Actually match the given path against the given pattern.
java.lang.String	extractPathWithinPattern(java.lang.String pattern, java.lang.String path) Given a pattern and a full path, determine the pattern-mapped part.
java.util.Map<java.lang.String,java.lang.String>	extractUriTemplateVariables(java.lang.String pattern, java.lang.String path) Given a pattern and a full path, extract the URI template variables.
java.util.Comparator<java.lang.String>	getPatternComparator(java.lang.String path) Given a full path, returns a Comparator suitable for sorting patterns in order of explicitness.
protected AntPathMatcher.AntPathStringMatcher	getStringMatcher(java.lang.String pattern) Build or retrieve an AntPathMatcher.AntPathStringMatcher for the given pattern.
boolean	isPattern(java.lang.String path) Does the given path represent a pattern that can be matched by an implementation of this interface?
private boolean	isPotentialMatch(java.lang.String path, java.lang.String[] pattDirs)
private boolean	isWildcardChar(char c)
boolean	match(java.lang.String pattern, java.lang.String path) Match the given path against the given pattern, according to this PathMatcher's matching strategy.
boolean	matchStart(java.lang.String pattern, java.lang.String path) Match the given path against the corresponding part of the given pattern, according to this PathMatcher's matching strategy.
private boolean	matchStrings(java.lang.String pattern, java.lang.String str, java.util.Map<java.lang.String,java.lang.String> uriTemplateVariables) Test whether or not a string matches against a pattern.
void	setCachePatterns(boolean cachePatterns) Specify whether to cache parsed pattern metadata for patterns passed into this matcher's match(java.lang.String, java.lang.String) method.
void	setCaseSensitive(boolean caseSensitive) Specify whether to perform pattern matching in a case-sensitive fashion.
void	setPathSeparator(java.lang.String pathSeparator) Set the path separator to use for pattern parsing.
void	setTrimTokens(boolean trimTokens) Specify whether to trim tokenized paths and patterns.
private int	skipSegment(char[] chars, int pos, java.lang.String prefix)
private int	skipSeparator(java.lang.String path, int pos, java.lang.String separator)
protected java.lang.String[]	tokenizePath(java.lang.String path) Tokenize the given path String into parts, based on this matcher's settings.
protected java.lang.String[]	tokenizePattern(java.lang.String pattern) Tokenize the given path pattern into parts, based on this matcher's settings.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_PATH_SEPARATOR

public static final java.lang.String DEFAULT_PATH_SEPARATOR

Default path separator: "/"

See Also:

Constant Field Values

CACHE_TURNOFF_THRESHOLD

private static final int CACHE_TURNOFF_THRESHOLD

See Also:

Constant Field Values

VARIABLE_PATTERN

private static final java.util.regex.Pattern VARIABLE_PATTERN

WILDCARD_CHARS

private static final char[] WILDCARD_CHARS

pathSeparator

private java.lang.String pathSeparator

pathSeparatorPatternCache

private AntPathMatcher.PathSeparatorPatternCache pathSeparatorPatternCache

caseSensitive

private boolean caseSensitive

trimTokens

private boolean trimTokens

cachePatterns

private volatile java.lang.Boolean cachePatterns

tokenizedPatternCache

private final java.util.Map<java.lang.String,java.lang.String[]> tokenizedPatternCache

stringMatcherCache

final java.util.Map<java.lang.String,AntPathMatcher.AntPathStringMatcher> stringMatcherCache

Constructor Detail

AntPathMatcher

public AntPathMatcher()

Create a new instance with the DEFAULT_PATH_SEPARATOR.

AntPathMatcher

public AntPathMatcher(java.lang.String pathSeparator)

A convenient, alternative constructor to use with a custom path separator.

Parameters:

pathSeparator - the path separator to use, must not be null.

Since:

4.1

Method Detail

setPathSeparator

public void setPathSeparator(java.lang.String pathSeparator)

Set the path separator to use for pattern parsing. Default is "/", as in Ant.

Parameters:

pathSeparator - value to be used as path separator

setCaseSensitive

public void setCaseSensitive(boolean caseSensitive)

Specify whether to perform pattern matching in a case-sensitive fashion.

Default is true. Switch this to false for case-insensitive matching.

setTrimTokens

public void setTrimTokens(boolean trimTokens)

Specify whether to trim tokenized paths and patterns.

Default is false.

setCachePatterns

public void setCachePatterns(boolean cachePatterns)

Specify whether to cache parsed pattern metadata for patterns passed into this matcher's match(java.lang.String, java.lang.String) method. A value of true activates an unlimited pattern cache; a value of false turns the pattern cache off completely.

Default is for the cache to be on, but with the variant to automatically turn it off when encountering too many patterns to cache at runtime (the threshold is 65536), assuming that arbitrary permutations of patterns are coming in, with little chance for encountering a recurring pattern.

Since:

4.0.1

See Also:

getStringMatcher(String)

deactivatePatternCache

private void deactivatePatternCache()

isPattern

public boolean isPattern(java.lang.String path)

Description copied from interface: PathMatcher

Does the given path represent a pattern that can be matched by an implementation of this interface?

If the return value is false, then the PathMatcher.match(java.lang.String, java.lang.String) method does not have to be used because direct equality comparisons on the static path Strings will lead to the same result.

Specified by:

isPattern in interface PathMatcher

Parameters:

path - the path String to check

Returns:

true if the given path represents a pattern

match

public boolean match(java.lang.String pattern,
                     java.lang.String path)

Description copied from interface: PathMatcher

Match the given path against the given pattern, according to this PathMatcher's matching strategy.

Specified by:

match in interface PathMatcher

Parameters:

pattern - the pattern to match against

path - the path String to test

Returns:

true if the supplied path matched, false if it didn't

matchStart

public boolean matchStart(java.lang.String pattern,
                          java.lang.String path)

Description copied from interface: PathMatcher

Match the given path against the corresponding part of the given pattern, according to this PathMatcher's matching strategy.

Determines whether the pattern at least matches as far as the given base path goes, assuming that a full path may then match as well.

Specified by:

matchStart in interface PathMatcher

Parameters:

pattern - the pattern to match against

path - the path String to test

Returns:

true if the supplied path matched, false if it didn't

doMatch

protected boolean doMatch(java.lang.String pattern,
                          java.lang.String path,
                          boolean fullMatch,
                          java.util.Map<java.lang.String,java.lang.String> uriTemplateVariables)

Actually match the given path against the given pattern.

Parameters:

pattern - the pattern to match against

path - the path String to test

fullMatch - whether a full pattern match is required (else a pattern match as far as the given base path goes is sufficient)

Returns:

true if the supplied path matched, false if it didn't

isPotentialMatch

private boolean isPotentialMatch(java.lang.String path,
                                 java.lang.String[] pattDirs)

skipSegment

private int skipSegment(char[] chars,
                        int pos,
                        java.lang.String prefix)

skipSeparator

private int skipSeparator(java.lang.String path,
                          int pos,
                          java.lang.String separator)

isWildcardChar

private boolean isWildcardChar(char c)

tokenizePattern

protected java.lang.String[] tokenizePattern(java.lang.String pattern)

Tokenize the given path pattern into parts, based on this matcher's settings.

Performs caching based on setCachePatterns(boolean), delegating to tokenizePath(String) for the actual tokenization algorithm.

Parameters:

pattern - the pattern to tokenize

Returns:

the tokenized pattern parts

tokenizePath

protected java.lang.String[] tokenizePath(java.lang.String path)

Tokenize the given path String into parts, based on this matcher's settings.

Parameters:

path - the path to tokenize

Returns:

the tokenized path parts

matchStrings

private boolean matchStrings(java.lang.String pattern,
                             java.lang.String str,
                             java.util.Map<java.lang.String,java.lang.String> uriTemplateVariables)

Test whether or not a string matches against a pattern.

Parameters:

pattern - the pattern to match against (never null)

str - the String which must be matched against the pattern (never null)

Returns:

true if the string matches against the pattern, or false otherwise

getStringMatcher

protected AntPathMatcher.AntPathStringMatcher getStringMatcher(java.lang.String pattern)

Build or retrieve an AntPathMatcher.AntPathStringMatcher for the given pattern.

The default implementation checks this AntPathMatcher's internal cache (see setCachePatterns(boolean)), creating a new AntPathStringMatcher instance if no cached copy is found.

When encountering too many patterns to cache at runtime (the threshold is 65536), it turns the default cache off, assuming that arbitrary permutations of patterns are coming in, with little chance for encountering a recurring pattern.

This method may be overridden to implement a custom cache strategy.

Parameters:

pattern - the pattern to match against (never null)

Returns:

a corresponding AntPathStringMatcher (never null)

See Also:

setCachePatterns(boolean)

extractPathWithinPattern

public java.lang.String extractPathWithinPattern(java.lang.String pattern,
                                                 java.lang.String path)

Given a pattern and a full path, determine the pattern-mapped part.

For example:

• '/docs/cvs/commit.html' and '/docs/cvs/commit.html -> ''
• '/docs/*' and '/docs/cvs/commit -> 'cvs/commit'
• '/docs/cvs/*.html' and '/docs/cvs/commit.html -> 'commit.html'
• '/docs/**' and '/docs/cvs/commit -> 'cvs/commit'
• '/docs/**\/*.html' and '/docs/cvs/commit.html -> 'cvs/commit.html'
• '/*.html' and '/docs/cvs/commit.html -> 'docs/cvs/commit.html'
• '*.html' and '/docs/cvs/commit.html -> '/docs/cvs/commit.html'
• '*' and '/docs/cvs/commit.html -> '/docs/cvs/commit.html'

Assumes that match(java.lang.String, java.lang.String) returns true for 'pattern' and 'path', but does not enforce this.

Specified by:

extractPathWithinPattern in interface PathMatcher

Parameters:

pattern - the path pattern

path - the full path to introspect

Returns:

the pattern-mapped part of the given path (never null)

extractUriTemplateVariables

public java.util.Map<java.lang.String,java.lang.String> extractUriTemplateVariables(java.lang.String pattern,
                                                                                    java.lang.String path)

Description copied from interface: PathMatcher

Given a pattern and a full path, extract the URI template variables. URI template variables are expressed through curly brackets ('{' and '}').

For example: For pattern "/hotels/{hotel}" and path "/hotels/1", this method will return a map containing "hotel"->"1".

Specified by:

extractUriTemplateVariables in interface PathMatcher

Parameters:

pattern - the path pattern, possibly containing URI templates

path - the full path to extract template variables from

Returns:

a map, containing variable names as keys; variables values as values

combine

public java.lang.String combine(java.lang.String pattern1,
                                java.lang.String pattern2)

Combine two patterns into a new pattern.

This implementation simply concatenates the two patterns, unless the first pattern contains a file extension match (e.g., *.html). In that case, the second pattern will be merged into the first. Otherwise, an IllegalArgumentException will be thrown.

Examples

Pattern 1	Pattern 2	Result
null	null
/hotels	null	/hotels
null	/hotels	/hotels
/hotels	/bookings	/hotels/bookings
/hotels	bookings	/hotels/bookings
/hotels/*	/bookings	/hotels/bookings
/hotels/**	/bookings	/hotels/**/bookings
/hotels	{hotel}	/hotels/{hotel}
/hotels/*	{hotel}	/hotels/{hotel}
/hotels/**	{hotel}	/hotels/**/{hotel}
/*.html	/hotels.html	/hotels.html
/*.html	/hotels	/hotels.html
/*.html	/*.txt	IllegalArgumentException

Specified by:

combine in interface PathMatcher

Parameters:

pattern1 - the first pattern

pattern2 - the second pattern

Returns:

the combination of the two patterns

Throws:

java.lang.IllegalArgumentException - if the two patterns cannot be combined

concat

private java.lang.String concat(java.lang.String path1,
                                java.lang.String path2)

getPatternComparator

public java.util.Comparator<java.lang.String> getPatternComparator(java.lang.String path)

Given a full path, returns a Comparator suitable for sorting patterns in order of explicitness.

ThisComparator will sort a list so that more specific patterns (without uri templates or wild cards) come before generic patterns. So given a list with the following patterns:

1. /hotels/new
2. /hotels/{hotel}
3. /hotels/*

the returned comparator will sort this list so that the order will be as indicated.

The full path given as parameter is used to test for exact matches. So when the given path is /hotels/2, the pattern /hotels/2 will be sorted before /hotels/1.

Specified by:

getPatternComparator in interface PathMatcher

Parameters:

path - the full path to use for comparison

Returns:

a comparator capable of sorting patterns in order of explicitness