org.springframework.util.AntPathMatcher Maven / Gradle / Ivy
/*
* Copyright 2002-2017 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.util;
import java.util.Comparator;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* {@link 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:
*
* - {@code ?} matches one character
* - {@code *} matches zero or more characters
* - {@code **} matches zero or more directories in a path
* - {@code {spring:[a-z]+}} matches the regexp {@code [a-z]+} as a path variable named "spring"
*
*
* Examples
*
* - {@code com/t?st.jsp} — matches {@code com/test.jsp} but also
* {@code com/tast.jsp} or {@code com/txst.jsp}
* - {@code com/*.jsp} — matches all {@code .jsp} files in the
* {@code com} directory
* com/**/test.jsp — matches all {@code test.jsp}
* files underneath the {@code com} pathorg/springframework/**/*.jsp — matches all
* {@code .jsp} files underneath the {@code org/springframework} pathorg/**/servlet/bla.jsp — matches
* {@code org/springframework/servlet/bla.jsp} but also
* {@code org/springframework/testing/servlet/bla.jsp} and {@code org/servlet/bla.jsp}- {@code com/{filename:\\w+}.jsp} will match {@code com/test.jsp} and assign the value {@code test}
* to the {@code 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.
*
* @author Alef Arendsen
* @author Juergen Hoeller
* @author Rob Harrop
* @author Arjen Poutsma
* @author Rossen Stoyanchev
* @author Sam Brannen
* @since 16.07.2003
*/
public class AntPathMatcher implements PathMatcher {
/** Default path separator: "/" */
public static final String DEFAULT_PATH_SEPARATOR = "/";
private static final int CACHE_TURNOFF_THRESHOLD = 65536;
private static final Pattern VARIABLE_PATTERN = Pattern.compile("\\{[^/]+?\\}");
private static final char[] WILDCARD_CHARS = { '*', '?', '{' };
private String pathSeparator;
private PathSeparatorPatternCache pathSeparatorPatternCache;
private boolean caseSensitive = true;
private boolean trimTokens = false;
private volatile Boolean cachePatterns;
private final Map tokenizedPatternCache = new ConcurrentHashMap(256);
final Map stringMatcherCache = new ConcurrentHashMap(256);
/**
* Create a new instance with the {@link #DEFAULT_PATH_SEPARATOR}.
*/
public AntPathMatcher() {
this.pathSeparator = DEFAULT_PATH_SEPARATOR;
this.pathSeparatorPatternCache = new PathSeparatorPatternCache(DEFAULT_PATH_SEPARATOR);
}
/**
* A convenient, alternative constructor to use with a custom path separator.
* @param pathSeparator the path separator to use, must not be {@code null}.
* @since 4.1
*/
public AntPathMatcher(String pathSeparator) {
Assert.notNull(pathSeparator, "'pathSeparator' is required");
this.pathSeparator = pathSeparator;
this.pathSeparatorPatternCache = new PathSeparatorPatternCache(pathSeparator);
}
/**
* Set the path separator to use for pattern parsing.
* Default is "/", as in Ant.
*/
public void setPathSeparator(String pathSeparator) {
this.pathSeparator = (pathSeparator != null ? pathSeparator : DEFAULT_PATH_SEPARATOR);
this.pathSeparatorPatternCache = new PathSeparatorPatternCache(this.pathSeparator);
}
/**
* Specify whether to perform pattern matching in a case-sensitive fashion.
*
Default is {@code true}. Switch this to {@code false} for case-insensitive matching.
* @since 4.2
*/
public void setCaseSensitive(boolean caseSensitive) {
this.caseSensitive = caseSensitive;
}
/**
* Specify whether to trim tokenized paths and patterns.
*
Default is {@code false}.
*/
public void setTrimTokens(boolean trimTokens) {
this.trimTokens = trimTokens;
}
/**
* Specify whether to cache parsed pattern metadata for patterns passed
* into this matcher's {@link #match} method. A value of {@code true}
* activates an unlimited pattern cache; a value of {@code 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 #getStringMatcher(String)
*/
public void setCachePatterns(boolean cachePatterns) {
this.cachePatterns = cachePatterns;
}
private void deactivatePatternCache() {
this.cachePatterns = false;
this.tokenizedPatternCache.clear();
this.stringMatcherCache.clear();
}
@Override
public boolean isPattern(String path) {
return (path.indexOf('*') != -1 || path.indexOf('?') != -1);
}
@Override
public boolean match(String pattern, String path) {
return doMatch(pattern, path, true, null);
}
@Override
public boolean matchStart(String pattern, String path) {
return doMatch(pattern, path, false, null);
}
/**
* Actually match the given {@code path} against the given {@code pattern}.
* @param pattern the pattern to match against
* @param path the path String to test
* @param fullMatch whether a full pattern match is required (else a pattern match
* as far as the given base path goes is sufficient)
* @return {@code true} if the supplied {@code path} matched, {@code false} if it didn't
*/
protected boolean doMatch(String pattern, String path, boolean fullMatch, Map uriTemplateVariables) {
if (path.startsWith(this.pathSeparator) != pattern.startsWith(this.pathSeparator)) {
return false;
}
String[] pattDirs = tokenizePattern(pattern);
if (fullMatch && this.caseSensitive && !isPotentialMatch(path, pattDirs)) {
return false;
}
String[] pathDirs = tokenizePath(path);
int pattIdxStart = 0;
int pattIdxEnd = pattDirs.length - 1;
int pathIdxStart = 0;
int pathIdxEnd = pathDirs.length - 1;
// Match all elements up to the first **
while (pattIdxStart <= pattIdxEnd && pathIdxStart <= pathIdxEnd) {
String pattDir = pattDirs[pattIdxStart];
if ("**".equals(pattDir)) {
break;
}
if (!matchStrings(pattDir, pathDirs[pathIdxStart], uriTemplateVariables)) {
return false;
}
pattIdxStart++;
pathIdxStart++;
}
if (pathIdxStart > pathIdxEnd) {
// Path is exhausted, only match if rest of pattern is * or **'s
if (pattIdxStart > pattIdxEnd) {
return (pattern.endsWith(this.pathSeparator) == path.endsWith(this.pathSeparator));
}
if (!fullMatch) {
return true;
}
if (pattIdxStart == pattIdxEnd && pattDirs[pattIdxStart].equals("*") && path.endsWith(this.pathSeparator)) {
return true;
}
for (int i = pattIdxStart; i <= pattIdxEnd; i++) {
if (!pattDirs[i].equals("**")) {
return false;
}
}
return true;
}
else if (pattIdxStart > pattIdxEnd) {
// String not exhausted, but pattern is. Failure.
return false;
}
else if (!fullMatch && "**".equals(pattDirs[pattIdxStart])) {
// Path start definitely matches due to "**" part in pattern.
return true;
}
// up to last '**'
while (pattIdxStart <= pattIdxEnd && pathIdxStart <= pathIdxEnd) {
String pattDir = pattDirs[pattIdxEnd];
if (pattDir.equals("**")) {
break;
}
if (!matchStrings(pattDir, pathDirs[pathIdxEnd], uriTemplateVariables)) {
return false;
}
pattIdxEnd--;
pathIdxEnd--;
}
if (pathIdxStart > pathIdxEnd) {
// String is exhausted
for (int i = pattIdxStart; i <= pattIdxEnd; i++) {
if (!pattDirs[i].equals("**")) {
return false;
}
}
return true;
}
while (pattIdxStart != pattIdxEnd && pathIdxStart <= pathIdxEnd) {
int patIdxTmp = -1;
for (int i = pattIdxStart + 1; i <= pattIdxEnd; i++) {
if (pattDirs[i].equals("**")) {
patIdxTmp = i;
break;
}
}
if (patIdxTmp == pattIdxStart + 1) {
// '**/**' situation, so skip one
pattIdxStart++;
continue;
}
// Find the pattern between padIdxStart & padIdxTmp in str between
// strIdxStart & strIdxEnd
int patLength = (patIdxTmp - pattIdxStart - 1);
int strLength = (pathIdxEnd - pathIdxStart + 1);
int foundIdx = -1;
strLoop:
for (int i = 0; i <= strLength - patLength; i++) {
for (int j = 0; j < patLength; j++) {
String subPat = pattDirs[pattIdxStart + j + 1];
String subStr = pathDirs[pathIdxStart + i + j];
if (!matchStrings(subPat, subStr, uriTemplateVariables)) {
continue strLoop;
}
}
foundIdx = pathIdxStart + i;
break;
}
if (foundIdx == -1) {
return false;
}
pattIdxStart = patIdxTmp;
pathIdxStart = foundIdx + patLength;
}
for (int i = pattIdxStart; i <= pattIdxEnd; i++) {
if (!pattDirs[i].equals("**")) {
return false;
}
}
return true;
}
private boolean isPotentialMatch(String path, String[] pattDirs) {
if (!this.trimTokens) {
int pos = 0;
for (String pattDir : pattDirs) {
int skipped = skipSeparator(path, pos, this.pathSeparator);
pos += skipped;
skipped = skipSegment(path, pos, pattDir);
if (skipped < pattDir.length()) {
return (skipped > 0 || (pattDir.length() > 0 && isWildcardChar(pattDir.charAt(0))));
}
pos += skipped;
}
}
return true;
}
private int skipSegment(String path, int pos, String prefix) {
int skipped = 0;
for (int i = 0; i < prefix.length(); i++) {
char c = prefix.charAt(i);
if (isWildcardChar(c)) {
return skipped;
}
int currPos = pos + skipped;
if (currPos >= path.length()) {
return 0;
}
if (c == path.charAt(currPos)) {
skipped++;
}
}
return skipped;
}
private int skipSeparator(String path, int pos, String separator) {
int skipped = 0;
while (path.startsWith(separator, pos + skipped)) {
skipped += separator.length();
}
return skipped;
}
private boolean isWildcardChar(char c) {
for (char candidate : WILDCARD_CHARS) {
if (c == candidate) {
return true;
}
}
return false;
}
/**
* Tokenize the given path pattern into parts, based on this matcher's settings.
* Performs caching based on {@link #setCachePatterns}, delegating to
* {@link #tokenizePath(String)} for the actual tokenization algorithm.
* @param pattern the pattern to tokenize
* @return the tokenized pattern parts
*/
protected String[] tokenizePattern(String pattern) {
String[] tokenized = null;
Boolean cachePatterns = this.cachePatterns;
if (cachePatterns == null || cachePatterns.booleanValue()) {
tokenized = this.tokenizedPatternCache.get(pattern);
}
if (tokenized == null) {
tokenized = tokenizePath(pattern);
if (cachePatterns == null && this.tokenizedPatternCache.size() >= CACHE_TURNOFF_THRESHOLD) {
// Try to adapt to the runtime situation that we're encountering:
// There are obviously too many different patterns coming in here...
// So let's turn off the cache since the patterns are unlikely to be reoccurring.
deactivatePatternCache();
return tokenized;
}
if (cachePatterns == null || cachePatterns.booleanValue()) {
this.tokenizedPatternCache.put(pattern, tokenized);
}
}
return tokenized;
}
/**
* Tokenize the given path String into parts, based on this matcher's settings.
* @param path the path to tokenize
* @return the tokenized path parts
*/
protected String[] tokenizePath(String path) {
return StringUtils.tokenizeToStringArray(path, this.pathSeparator, this.trimTokens, true);
}
/**
* Test whether or not a string matches against a pattern.
* @param pattern the pattern to match against (never {@code null})
* @param str the String which must be matched against the pattern (never {@code null})
* @return {@code true} if the string matches against the pattern, or {@code false} otherwise
*/
private boolean matchStrings(String pattern, String str, Map uriTemplateVariables) {
return getStringMatcher(pattern).matchStrings(str, uriTemplateVariables);
}
/**
* Build or retrieve an {@link AntPathStringMatcher} for the given pattern.
* The default implementation checks this AntPathMatcher's internal cache
* (see {@link #setCachePatterns}), 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.
* @param pattern the pattern to match against (never {@code null})
* @return a corresponding AntPathStringMatcher (never {@code null})
* @see #setCachePatterns
*/
protected AntPathStringMatcher getStringMatcher(String pattern) {
AntPathStringMatcher matcher = null;
Boolean cachePatterns = this.cachePatterns;
if (cachePatterns == null || cachePatterns.booleanValue()) {
matcher = this.stringMatcherCache.get(pattern);
}
if (matcher == null) {
matcher = new AntPathStringMatcher(pattern, this.caseSensitive);
if (cachePatterns == null && this.stringMatcherCache.size() >= CACHE_TURNOFF_THRESHOLD) {
// Try to adapt to the runtime situation that we're encountering:
// There are obviously too many different patterns coming in here...
// So let's turn off the cache since the patterns are unlikely to be reoccurring.
deactivatePatternCache();
return matcher;
}
if (cachePatterns == null || cachePatterns.booleanValue()) {
this.stringMatcherCache.put(pattern, matcher);
}
}
return matcher;
}
/**
* Given a pattern and a full path, determine the pattern-mapped part.
For example:
* - '{@code /docs/cvs/commit.html}' and '{@code /docs/cvs/commit.html} -> ''
* - '{@code /docs/*}' and '{@code /docs/cvs/commit} -> '{@code cvs/commit}'
* - '{@code /docs/cvs/*.html}' and '{@code /docs/cvs/commit.html} -> '{@code commit.html}'
* - '{@code /docs/**}' and '{@code /docs/cvs/commit} -> '{@code cvs/commit}'
* - '{@code /docs/**\/*.html}' and '{@code /docs/cvs/commit.html} -> '{@code cvs/commit.html}'
* - '{@code /*.html}' and '{@code /docs/cvs/commit.html} -> '{@code docs/cvs/commit.html}'
* - '{@code *.html}' and '{@code /docs/cvs/commit.html} -> '{@code /docs/cvs/commit.html}'
* - '{@code *}' and '{@code /docs/cvs/commit.html} -> '{@code /docs/cvs/commit.html}'
* Assumes that {@link #match} returns {@code true} for '{@code pattern}' and '{@code path}', but
* does not enforce this.
*/
@Override
public String extractPathWithinPattern(String pattern, String path) {
String[] patternParts = StringUtils.tokenizeToStringArray(pattern, this.pathSeparator, this.trimTokens, true);
String[] pathParts = StringUtils.tokenizeToStringArray(path, this.pathSeparator, this.trimTokens, true);
StringBuilder builder = new StringBuilder();
boolean pathStarted = false;
for (int segment = 0; segment < patternParts.length; segment++) {
String patternPart = patternParts[segment];
if (patternPart.indexOf('*') > -1 || patternPart.indexOf('?') > -1) {
for (; segment < pathParts.length; segment++) {
if (pathStarted || (segment == 0 && !pattern.startsWith(this.pathSeparator))) {
builder.append(this.pathSeparator);
}
builder.append(pathParts[segment]);
pathStarted = true;
}
}
}
return builder.toString();
}
@Override
public Map extractUriTemplateVariables(String pattern, String path) {
Map variables = new LinkedHashMap();
boolean result = doMatch(pattern, path, true, variables);
if (!result) {
throw new IllegalStateException("Pattern \"" + pattern + "\" is not a match for \"" + path + "\"");
}
return variables;
}
/**
* 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., {@code *.html}).
* In that case, the second pattern will be merged into the first. Otherwise,
* an {@code IllegalArgumentException} will be thrown.
*
Examples
*
* Pattern 1 Pattern 2 Result {@code null} {@code null} /hotels {@code null} /hotels {@code 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 {@code IllegalArgumentException}
* @param pattern1 the first pattern
* @param pattern2 the second pattern
* @return the combination of the two patterns
* @throws IllegalArgumentException if the two patterns cannot be combined
*/
@Override
public String combine(String pattern1, String pattern2) {
if (!StringUtils.hasText(pattern1) && !StringUtils.hasText(pattern2)) {
return "";
}
if (!StringUtils.hasText(pattern1)) {
return pattern2;
}
if (!StringUtils.hasText(pattern2)) {
return pattern1;
}
boolean pattern1ContainsUriVar = (pattern1.indexOf('{') != -1);
if (!pattern1.equals(pattern2) && !pattern1ContainsUriVar && match(pattern1, pattern2)) {
// /* + /hotel -> /hotel ; "/*.*" + "/*.html" -> /*.html
// However /user + /user -> /usr/user ; /{foo} + /bar -> /{foo}/bar
return pattern2;
}
// /hotels/* + /booking -> /hotels/booking
// /hotels/* + booking -> /hotels/booking
if (pattern1.endsWith(this.pathSeparatorPatternCache.getEndsOnWildCard())) {
return concat(pattern1.substring(0, pattern1.length() - 2), pattern2);
}
// /hotels/** + /booking -> /hotels/**/booking
// /hotels/** + booking -> /hotels/**/booking
if (pattern1.endsWith(this.pathSeparatorPatternCache.getEndsOnDoubleWildCard())) {
return concat(pattern1, pattern2);
}
int starDotPos1 = pattern1.indexOf("*.");
if (pattern1ContainsUriVar || starDotPos1 == -1 || this.pathSeparator.equals(".")) {
// simply concatenate the two patterns
return concat(pattern1, pattern2);
}
String ext1 = pattern1.substring(starDotPos1 + 1);
int dotPos2 = pattern2.indexOf('.');
String file2 = (dotPos2 == -1 ? pattern2 : pattern2.substring(0, dotPos2));
String ext2 = (dotPos2 == -1 ? "" : pattern2.substring(dotPos2));
boolean ext1All = (ext1.equals(".*") || ext1.equals(""));
boolean ext2All = (ext2.equals(".*") || ext2.equals(""));
if (!ext1All && !ext2All) {
throw new IllegalArgumentException("Cannot combine patterns: " + pattern1 + " vs " + pattern2);
}
String ext = (ext1All ? ext2 : ext1);
return file2 + ext;
}
private String concat(String path1, String path2) {
boolean path1EndsWithSeparator = path1.endsWith(this.pathSeparator);
boolean path2StartsWithSeparator = path2.startsWith(this.pathSeparator);
if (path1EndsWithSeparator && path2StartsWithSeparator) {
return path1 + path2.substring(1);
}
else if (path1EndsWithSeparator || path2StartsWithSeparator) {
return path1 + path2;
}
else {
return path1 + this.pathSeparator + path2;
}
}
/**
* Given a full path, returns a {@link Comparator} suitable for sorting patterns in order of
* explicitness.
* This{@code Comparator} will {@linkplain java.util.Collections#sort(List, Comparator) 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:
*
* - {@code /hotels/new}
* - {@code /hotels/{hotel}}
- {@code /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 {@code /hotels/2}, the pattern {@code /hotels/2} will be sorted before {@code /hotels/1}.
* @param path the full path to use for comparison
* @return a comparator capable of sorting patterns in order of explicitness
*/
@Override
public Comparator getPatternComparator(String path) {
return new AntPatternComparator(path);
}
/**
* Tests whether or not a string matches against a pattern via a {@link Pattern}.
* The pattern may contain special characters: '*' means zero or more characters; '?' means one and
* only one character; '{' and '}' indicate a URI template pattern. For example /users/{user}.
*/
protected static class AntPathStringMatcher {
private static final Pattern GLOB_PATTERN = Pattern.compile("\\?|\\*|\\{((?:\\{[^/]+?\\}|[^/{}]|\\\\[{}])+?)\\}");
private static final String DEFAULT_VARIABLE_PATTERN = "(.*)";
private final Pattern pattern;
private final List variableNames = new LinkedList();
public AntPathStringMatcher(String pattern) {
this(pattern, true);
}
public AntPathStringMatcher(String pattern, boolean caseSensitive) {
StringBuilder patternBuilder = new StringBuilder();
Matcher matcher = GLOB_PATTERN.matcher(pattern);
int end = 0;
while (matcher.find()) {
patternBuilder.append(quote(pattern, end, matcher.start()));
String match = matcher.group();
if ("?".equals(match)) {
patternBuilder.append('.');
}
else if ("*".equals(match)) {
patternBuilder.append(".*");
}
else if (match.startsWith("{") && match.endsWith("}")) {
int colonIdx = match.indexOf(':');
if (colonIdx == -1) {
patternBuilder.append(DEFAULT_VARIABLE_PATTERN);
this.variableNames.add(matcher.group(1));
}
else {
String variablePattern = match.substring(colonIdx + 1, match.length() - 1);
patternBuilder.append('(');
patternBuilder.append(variablePattern);
patternBuilder.append(')');
String variableName = match.substring(1, colonIdx);
this.variableNames.add(variableName);
}
}
end = matcher.end();
}
patternBuilder.append(quote(pattern, end, pattern.length()));
this.pattern = (caseSensitive ? Pattern.compile(patternBuilder.toString()) :
Pattern.compile(patternBuilder.toString(), Pattern.CASE_INSENSITIVE));
}
private String quote(String s, int start, int end) {
if (start == end) {
return "";
}
return Pattern.quote(s.substring(start, end));
}
/**
* Main entry point.
* @return {@code true} if the string matches against the pattern, or {@code false} otherwise.
*/
public boolean matchStrings(String str, Map uriTemplateVariables) {
Matcher matcher = this.pattern.matcher(str);
if (matcher.matches()) {
if (uriTemplateVariables != null) {
// SPR-8455
if (this.variableNames.size() != matcher.groupCount()) {
throw new IllegalArgumentException("The number of capturing groups in the pattern segment " +
this.pattern + " does not match the number of URI template variables it defines, " +
"which can occur if capturing groups are used in a URI template regex. " +
"Use non-capturing groups instead.");
}
for (int i = 1; i <= matcher.groupCount(); i++) {
String name = this.variableNames.get(i - 1);
String value = matcher.group(i);
uriTemplateVariables.put(name, value);
}
}
return true;
}
else {
return false;
}
}
}
/**
* The default {@link Comparator} implementation returned by
* {@link #getPatternComparator(String)}.
* In order, the most "generic" pattern is determined by the following:
*
* - if it's null or a capture all pattern (i.e. it is equal to "/**")
* - if the other pattern is an actual match
* - if it's a catch-all pattern (i.e. it ends with "**"
* - if it's got more "*" than the other pattern
* - if it's got more "{foo}" than the other pattern
* - if it's shorter than the other pattern
*
*/
protected static class AntPatternComparator implements Comparator {
private final String path;
public AntPatternComparator(String path) {
this.path = path;
}
/**
* Compare two patterns to determine which should match first, i.e. which
* is the most specific regarding the current path.
* @return a negative integer, zero, or a positive integer as pattern1 is
* more specific, equally specific, or less specific than pattern2.
*/
@Override
public int compare(String pattern1, String pattern2) {
PatternInfo info1 = new PatternInfo(pattern1);
PatternInfo info2 = new PatternInfo(pattern2);
if (info1.isLeastSpecific() && info2.isLeastSpecific()) {
return 0;
}
else if (info1.isLeastSpecific()) {
return 1;
}
else if (info2.isLeastSpecific()) {
return -1;
}
boolean pattern1EqualsPath = pattern1.equals(path);
boolean pattern2EqualsPath = pattern2.equals(path);
if (pattern1EqualsPath && pattern2EqualsPath) {
return 0;
}
else if (pattern1EqualsPath) {
return -1;
}
else if (pattern2EqualsPath) {
return 1;
}
if (info1.isPrefixPattern() && info2.getDoubleWildcards() == 0) {
return 1;
}
else if (info2.isPrefixPattern() && info1.getDoubleWildcards() == 0) {
return -1;
}
if (info1.getTotalCount() != info2.getTotalCount()) {
return info1.getTotalCount() - info2.getTotalCount();
}
if (info1.getLength() != info2.getLength()) {
return info2.getLength() - info1.getLength();
}
if (info1.getSingleWildcards() < info2.getSingleWildcards()) {
return -1;
}
else if (info2.getSingleWildcards() < info1.getSingleWildcards()) {
return 1;
}
if (info1.getUriVars() < info2.getUriVars()) {
return -1;
}
else if (info2.getUriVars() < info1.getUriVars()) {
return 1;
}
return 0;
}
/**
* Value class that holds information about the pattern, e.g. number of
* occurrences of "*", "**", and "{" pattern elements.
*/
private static class PatternInfo {
private final String pattern;
private int uriVars;
private int singleWildcards;
private int doubleWildcards;
private boolean catchAllPattern;
private boolean prefixPattern;
private Integer length;
public PatternInfo(String pattern) {
this.pattern = pattern;
if (this.pattern != null) {
initCounters();
this.catchAllPattern = this.pattern.equals("/**");
this.prefixPattern = !this.catchAllPattern && this.pattern.endsWith("/**");
}
if (this.uriVars == 0) {
this.length = (this.pattern != null ? this.pattern.length() : 0);
}
}
protected void initCounters() {
int pos = 0;
while (pos < this.pattern.length()) {
if (this.pattern.charAt(pos) == '{') {
this.uriVars++;
pos++;
}
else if (this.pattern.charAt(pos) == '*') {
if (pos + 1 < this.pattern.length() && this.pattern.charAt(pos + 1) == '*') {
this.doubleWildcards++;
pos += 2;
}
else if (pos > 0 && !this.pattern.substring(pos - 1).equals(".*")) {
this.singleWildcards++;
pos++;
}
else {
pos++;
}
}
else {
pos++;
}
}
}
public int getUriVars() {
return this.uriVars;
}
public int getSingleWildcards() {
return this.singleWildcards;
}
public int getDoubleWildcards() {
return this.doubleWildcards;
}
public boolean isLeastSpecific() {
return (this.pattern == null || this.catchAllPattern);
}
public boolean isPrefixPattern() {
return this.prefixPattern;
}
public int getTotalCount() {
return this.uriVars + this.singleWildcards + (2 * this.doubleWildcards);
}
/**
* Returns the length of the given pattern, where template variables are considered to be 1 long.
*/
public int getLength() {
if (this.length == null) {
this.length = VARIABLE_PATTERN.matcher(this.pattern).replaceAll("#").length();
}
return this.length;
}
}
}
/**
* A simple cache for patterns that depend on the configured path separator.
*/
private static class PathSeparatorPatternCache {
private final String endsOnWildCard;
private final String endsOnDoubleWildCard;
public PathSeparatorPatternCache(String pathSeparator) {
this.endsOnWildCard = pathSeparator + "*";
this.endsOnDoubleWildCard = pathSeparator + "**";
}
public String getEndsOnWildCard() {
return this.endsOnWildCard;
}
public String getEndsOnDoubleWildCard() {
return this.endsOnDoubleWildCard;
}
}
}