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.tapestry.web; 016 017 import java.util.Locale; 018 019 import org.apache.hivemind.util.LocalizedNameGenerator; 020 import org.apache.hivemind.util.LocalizedResource; 021 022 /** 023 * Finds localized resources within a {@link org.apache.tapestry.web.WebContext}.. 024 * 025 * @author Howard Lewis Ship 026 * @since 4.0 027 */ 028 029 public class LocalizedWebContextResourceFinder 030 { 031 private WebContext _context; 032 033 public LocalizedWebContextResourceFinder(WebContext context) 034 { 035 _context = context; 036 } 037 038 /** 039 * Resolves the resource, returning a path representing the closest match (with respect to the 040 * provided locale). Returns null if no match. 041 * <p> 042 * The provided path is split into a base path and a suffix (at the last period character). The 043 * locale will provide different suffixes to the base path and the first match is returned. 044 */ 045 046 public LocalizedResource resolve(String contextPath, Locale locale) 047 { 048 int dotx = contextPath.lastIndexOf('.'); 049 String basePath; 050 String suffix; 051 if (dotx >= 0) { 052 basePath = contextPath.substring(0, dotx); 053 suffix = contextPath.substring(dotx); 054 } 055 else 056 { 057 // Resource without extension 058 basePath = contextPath; 059 suffix = ""; 060 } 061 062 LocalizedNameGenerator generator = new LocalizedNameGenerator(basePath, locale, suffix); 063 064 while (generator.more()) 065 { 066 String candidatePath = generator.next(); 067 068 if (isExistingResource(candidatePath)) 069 return new LocalizedResource(candidatePath, generator.getCurrentLocale()); 070 } 071 072 return null; 073 } 074 075 private boolean isExistingResource(String path) 076 { 077 return _context.getResource(path) != null; 078 } 079 }