| /** |
| * Copyright (C) 2008 Google Inc. |
| * |
| * 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 |
| * |
| * http://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 com.google.inject.servlet; |
| |
| import java.util.regex.Matcher; |
| import java.util.regex.Pattern; |
| |
| /** |
| * An enumeration of the available URI-pattern matching styles |
| */ |
| enum UriPatternType { |
| SERVLET, REGEX; |
| |
| public static UriPatternMatcher get(UriPatternType type, String pattern) { |
| switch (type) { |
| case SERVLET: |
| return new ServletStyleUriPatternMatcher(pattern); |
| case REGEX: |
| return new RegexUriPatternMatcher(pattern); |
| default: |
| return null; |
| } |
| } |
| |
| /** |
| * Matches URIs using the pattern grammar of the Servlet API and web.xml. |
| * |
| * @author dhanji@gmail.com (Dhanji R. Prasanna) |
| */ |
| private static class ServletStyleUriPatternMatcher implements UriPatternMatcher { |
| private final String pattern; |
| private final Kind patternKind; |
| |
| private static enum Kind { PREFIX, SUFFIX, LITERAL, } |
| |
| public ServletStyleUriPatternMatcher(String pattern) { |
| if (pattern.startsWith("*")) { |
| this.pattern = pattern.substring(1); |
| this.patternKind = Kind.PREFIX; |
| } else if (pattern.endsWith("*")) { |
| this.pattern = pattern.substring(0, pattern.length() - 1); |
| this.patternKind = Kind.SUFFIX; |
| } else { |
| this.pattern = pattern; |
| this.patternKind = Kind.LITERAL; |
| } |
| } |
| |
| public boolean matches(String uri) { |
| if (null == uri) { |
| return false; |
| } |
| |
| if (patternKind == Kind.PREFIX) { |
| return uri.endsWith(pattern); |
| } else if (patternKind == Kind.SUFFIX) { |
| return uri.startsWith(pattern); |
| } |
| |
| //else treat as a literal |
| return pattern.equals(uri); |
| } |
| |
| public String extractPath(String path) { |
| if (patternKind == Kind.PREFIX) { |
| return null; |
| } else if (patternKind == Kind.SUFFIX) { |
| String extract = pattern; |
| |
| //trim the trailing '/' |
| if (extract.endsWith("/")) { |
| extract = extract.substring(0, extract.length() - 1); |
| } |
| |
| return extract; |
| } |
| |
| //else treat as literal |
| return path; |
| } |
| } |
| |
| /** |
| * Matchers URIs using a regular expression. |
| * |
| * @author dhanji@gmail.com (Dhanji R. Prasanna) |
| */ |
| private static class RegexUriPatternMatcher implements UriPatternMatcher { |
| private final Pattern pattern; |
| |
| public RegexUriPatternMatcher(String pattern) { |
| this.pattern = Pattern.compile(pattern); |
| } |
| |
| public boolean matches(String uri) { |
| return null != uri && this.pattern.matcher(uri).matches(); |
| } |
| |
| public String extractPath(String path) { |
| Matcher matcher = pattern.matcher(path); |
| if (matcher.matches() && matcher.groupCount() >= 1) { |
| |
| // Try to capture the everything before the regex begins to match |
| // the path. This is a rough approximation to try and get parity |
| // with the servlet style mapping where the path is a capture of |
| // the URI before the wildcard. |
| int end = matcher.start(1); |
| if (end < path.length()) { |
| return path.substring(0, end); |
| } |
| } |
| return null; |
| } |
| } |
| } |