001 // Copyright 2004, 2005 The Apache Software Foundation 002 // 003 // Licensed under the Apache License, Version 2.0 (the "License"); 004 // you may not use this file except in compliance with the License. 005 // You may obtain a copy of the License at 006 // 007 // http://www.apache.org/licenses/LICENSE-2.0 008 // 009 // Unless required by applicable law or agreed to in writing, software 010 // distributed under the License is distributed on an "AS IS" BASIS, 011 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012 // See the License for the specific language governing permissions and 013 // limitations under the License. 014 015 package org.apache.hivemind.util; 016 017 import java.net.MalformedURLException; 018 import java.util.Locale; 019 020 import javax.servlet.ServletContext; 021 022 /** 023 * Finds localized resources within the web application context. 024 * <p> 025 * Originally part of Tapestry 3.0. 026 * 027 * @see javax.servlet.ServletContext 028 * @author Howard Lewis Ship 029 * @since 1.1 030 */ 031 032 public class LocalizedContextResourceFinder 033 { 034 private ServletContext _context; 035 036 public LocalizedContextResourceFinder(ServletContext context) 037 { 038 _context = context; 039 } 040 041 /** 042 * Resolves the resource, returning a path representing the closest match (with respect to the 043 * provided locale). Returns null if no match. 044 * <p> 045 * The provided path is split into a base path and a suffix (at the last period character). The 046 * locale will provide different suffixes to the base path and the first match is returned. 047 */ 048 049 public LocalizedResource resolve(String contextPath, Locale locale) 050 { 051 int dotx = contextPath.lastIndexOf('.'); 052 String basePath; 053 String suffix; 054 if (dotx >= 0) { 055 basePath = contextPath.substring(0, dotx); 056 suffix = contextPath.substring(dotx); 057 } 058 else 059 { 060 // Resource without extension 061 basePath = contextPath; 062 suffix = ""; 063 } 064 065 LocalizedNameGenerator generator = new LocalizedNameGenerator(basePath, locale, suffix); 066 067 while (generator.more()) 068 { 069 String candidatePath = generator.next(); 070 071 if (isExistingResource(candidatePath)) 072 return new LocalizedResource(candidatePath, generator.getCurrentLocale()); 073 } 074 075 return null; 076 } 077 078 private boolean isExistingResource(String path) 079 { 080 try 081 { 082 return _context.getResource(path) != null; 083 } 084 catch (MalformedURLException ex) 085 { 086 return false; 087 } 088 } 089 }