1 /* 2 * Copyright (C) 2010 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 17 package com.google.clearsilver.jsilver.resourceloader; 18 19 import com.google.clearsilver.jsilver.exceptions.JSilverTemplateNotFoundException; 20 21 import java.io.File; 22 import java.io.FileInputStream; 23 import java.io.InputStreamReader; 24 import java.io.IOException; 25 import java.io.Reader; 26 27 /** 28 * Loads resources from a directory. 29 * 30 * @see ResourceLoader 31 */ 32 public class FileSystemResourceLoader extends BufferedResourceLoader { 33 34 private final File rootDir; 35 36 public FileSystemResourceLoader(File rootDir) { 37 this.rootDir = rootDir; 38 } 39 40 public FileSystemResourceLoader(String rootDir) { 41 this(new File(rootDir)); 42 } 43 44 @Override 45 public Reader open(String name) throws IOException { 46 File file = new File(rootDir, name); 47 // Check for non-directory rather than is-file so that reads from 48 // e.g. pipes work. 49 if (file.exists() && !file.isDirectory() && file.canRead()) { 50 return buffer(new InputStreamReader(new FileInputStream(file), getCharacterSet())); 51 } else { 52 return null; 53 } 54 } 55 56 @Override 57 public Reader openOrFail(String name) throws JSilverTemplateNotFoundException, IOException { 58 Reader reader = open(name); 59 if (reader == null) { 60 throw new JSilverTemplateNotFoundException("No file '" + name + "' inside directory '" 61 + rootDir + "'"); 62 } else { 63 return reader; 64 } 65 } 66 67 /** 68 * Some applications, e.g. online help, need to know when a file has changed due to a symlink 69 * modification hence the use of {@link File#getCanonicalFile()}, if possible. 70 */ 71 @Override 72 public Object getResourceVersionId(String filename) { 73 File file = new File(rootDir, filename); 74 // Check for non-directory rather than is-file so that reads from 75 // e.g. pipes work. 76 if (file.exists() && !file.isDirectory() && file.canRead()) { 77 String fullPath; 78 try { 79 fullPath = file.getCanonicalPath(); 80 } catch (IOException e) { 81 fullPath = file.getAbsolutePath(); 82 } 83 return String.format("%s@%s", fullPath, file.lastModified()); 84 } else { 85 return null; 86 } 87 } 88 } 89
