1 /** 2 * Copyright (C) 2008 Google Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.google.inject.servlet; 17 18 import java.util.regex.Matcher; 19 import java.util.regex.Pattern; 20 21 /** 22 * An enumeration of the available URI-pattern matching styles 23 * 24 * @since 3.0 25 */ 26 public enum UriPatternType { 27 SERVLET, REGEX; 28 29 static UriPatternMatcher get(UriPatternType type, String pattern) { 30 switch (type) { 31 case SERVLET: 32 return new ServletStyleUriPatternMatcher(pattern); 33 case REGEX: 34 return new RegexUriPatternMatcher(pattern); 35 default: 36 return null; 37 } 38 } 39 40 private static String getUri(String uri) { 41 // Strip out the query, if it existed in the URI. See issue 379. 42 int queryIdx = uri.indexOf('?'); 43 if (queryIdx != -1) { 44 uri = uri.substring(0, queryIdx); 45 } 46 return uri; 47 } 48 49 /** 50 * Matches URIs using the pattern grammar of the Servlet API and web.xml. 51 * 52 * @author dhanji (at) gmail.com (Dhanji R. Prasanna) 53 */ 54 private static class ServletStyleUriPatternMatcher implements UriPatternMatcher { 55 private final String pattern; 56 private final Kind patternKind; 57 58 private static enum Kind { PREFIX, SUFFIX, LITERAL, } 59 60 public ServletStyleUriPatternMatcher(String pattern) { 61 if (pattern.startsWith("*")) { 62 this.pattern = pattern.substring(1); 63 this.patternKind = Kind.PREFIX; 64 } else if (pattern.endsWith("*")) { 65 this.pattern = pattern.substring(0, pattern.length() - 1); 66 this.patternKind = Kind.SUFFIX; 67 } else { 68 this.pattern = pattern; 69 this.patternKind = Kind.LITERAL; 70 } 71 } 72 73 public boolean matches(String uri) { 74 if (null == uri) { 75 return false; 76 } 77 78 uri = getUri(uri); 79 if (patternKind == Kind.PREFIX) { 80 return uri.endsWith(pattern); 81 } else if (patternKind == Kind.SUFFIX) { 82 return uri.startsWith(pattern); 83 } 84 85 //else treat as a literal 86 return pattern.equals(uri); 87 } 88 89 public String extractPath(String path) { 90 if (patternKind == Kind.PREFIX) { 91 return null; 92 } else if (patternKind == Kind.SUFFIX) { 93 String extract = pattern; 94 95 //trim the trailing '/' 96 if (extract.endsWith("/")) { 97 extract = extract.substring(0, extract.length() - 1); 98 } 99 100 return extract; 101 } 102 103 //else treat as literal 104 return path; 105 } 106 107 public UriPatternType getPatternType() { 108 return UriPatternType.SERVLET; 109 } 110 } 111 112 /** 113 * Matches URIs using a regular expression. 114 * 115 * @author dhanji (at) gmail.com (Dhanji R. Prasanna) 116 */ 117 private static class RegexUriPatternMatcher implements UriPatternMatcher { 118 private final Pattern pattern; 119 120 public RegexUriPatternMatcher(String pattern) { 121 this.pattern = Pattern.compile(pattern); 122 } 123 124 public boolean matches(String uri) { 125 return null != uri && this.pattern.matcher(getUri(uri)).matches(); 126 } 127 128 public String extractPath(String path) { 129 Matcher matcher = pattern.matcher(path); 130 if (matcher.matches() && matcher.groupCount() >= 1) { 131 132 // Try to capture the everything before the regex begins to match 133 // the path. This is a rough approximation to try and get parity 134 // with the servlet style mapping where the path is a capture of 135 // the URI before the wildcard. 136 int end = matcher.start(1); 137 if (end < path.length()) { 138 return path.substring(0, end); 139 } 140 } 141 return null; 142 } 143 144 public UriPatternType getPatternType() { 145 return UriPatternType.REGEX; 146 } 147 } 148 } 149
