001 /*
002 * This file is part of the Echo Point Project. This project is a collection
003 * of Components that have extended the Echo Web Application Framework.
004 *
005 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
006 *
007 * The contents of this file are subject to the Mozilla Public License Version
008 * 1.1 (the "License"); you may not use this file except in compliance with
009 * the License. You may obtain a copy of the License at
010 * http://www.mozilla.org/MPL/
011 *
012 * Software distributed under the License is distributed on an "AS IS" basis,
013 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
014 * for the specific language governing rights and limitations under the
015 * License.
016 *
017 * Alternatively, the contents of this file may be used under the terms of
018 * either the GNU General Public License Version 2 or later (the "GPL"), or
019 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
020 * in which case the provisions of the GPL or the LGPL are applicable instead
021 * of those above. If you wish to allow use of your version of this file only
022 * under the terms of either the GPL or the LGPL, and not to allow others to
023 * use your version of this file under the terms of the MPL, indicate your
024 * decision by deleting the provisions above and replace them with the notice
025 * and other provisions required by the GPL or the LGPL. If you do not delete
026 * the provisions above, a recipient may use your version of this file under
027 * the terms of any one of the MPL, the GPL or the LGPL.
028 */
029 package echopoint.template.ui;
030
031 import echopoint.util.StringPeerFactory;
032
033 import java.util.Map;
034 import java.util.WeakHashMap;
035
036
037 /**
038 * <code>TemplateCompilerLoader</code> is repsonsible for finding
039 * a template compiler instance for a given content type
040 */
041 public class TemplateCompilerLoader {
042
043 private static final String PEERS_PATH = "META-INF/echopoint/template/TemplateCompilers.properties";
044
045 private static final Map classLoaderToLoaderMap = new WeakHashMap();
046
047 /**
048 * Creates or retrieves a <code>TemplateCompilerLoader</code>
049 * givena <code>ClassLoader</code>.
050 *
051 * @param classLoader the <code>ClassLoader</code> to use for
052 * dynamically loading classes
053 *
054 * @return the <code>TemplateCompilerLoader</code>
055 */
056 public static TemplateCompilerLoader forClassLoader(ClassLoader classLoader) {
057 synchronized(classLoaderToLoaderMap) {
058 TemplateCompilerLoader loader = (TemplateCompilerLoader) classLoaderToLoaderMap.get(classLoader);
059 if (loader == null) {
060 loader = new TemplateCompilerLoader(classLoader);
061 classLoaderToLoaderMap.put(classLoader, loader);
062 }
063 return loader;
064 }
065 }
066
067 private StringPeerFactory peerFactory;
068
069 /**
070 * Creates a new <code>TemplateCompilerLoader</code>.
071 *
072 * @param classLoader the <code>ClassLoader</code> to use for
073 * dynamically loading property classes
074 */
075 private TemplateCompilerLoader(ClassLoader classLoader) {
076 super();
077 peerFactory = new StringPeerFactory(PEERS_PATH, classLoader);
078 }
079
080 /**
081 * Returns the <code>TemplateCompiler</code> that can compile
082 * the given content type.
083 *
084 * @param contentType - the content type of the template data
085 * @return the XML parsing peer
086 */
087 public TemplateCompiler getTemplateCompiler(String contentType) {
088 return (TemplateCompiler) peerFactory.getPeer(contentType);
089 }
090 }