KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > apache > cocoon > woody > event > impl > JavaClassWidgetListenerBuilder


1 /*
2  * Copyright 1999-2004 The Apache Software Foundation.
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 package org.apache.cocoon.woody.event.impl;
17
18 import org.apache.cocoon.util.ClassUtils;
19 import org.apache.cocoon.woody.event.WidgetListener;
20 import org.apache.cocoon.woody.event.WidgetListenerBuilder;
21 import org.apache.cocoon.woody.util.DomHelper;
22 import org.w3c.dom.Element JavaDoc;
23
24 /**
25  * A {@link WidgetListenerBuilder} that creates java classes.
26  * <p>
27  * The syntax for this listener is as follows :<br/>
28  * <pre>
29  * &lt;java class="com.my.SuperListener"/&gt;
30  * </pre>
31  *
32  * @author <a HREF="http://www.apache.org/~sylvain/">Sylvain Wallez</a>
33  * @version CVS $Id: JavaClassWidgetListenerBuilder.java 30932 2004-07-29 17:35:38Z vgritsenko $
34  */
35 public class JavaClassWidgetListenerBuilder implements WidgetListenerBuilder {
36
37     public static final JavaClassWidgetListenerBuilder INSTANCE = new JavaClassWidgetListenerBuilder();
38
39     public WidgetListener buildListener(Element JavaDoc element, Class JavaDoc listenerClass) throws Exception JavaDoc {
40
41         String JavaDoc name = DomHelper.getAttribute(element, "class");
42
43         Object JavaDoc listener = ClassUtils.newInstance(name);
44         if (listenerClass.isAssignableFrom(listener.getClass())) {
45             // FIXME : apply filecyclehelper
46 return (WidgetListener)listener;
47         } else {
48             throw new Exception JavaDoc("Class " + listener.getClass() + " is not a " + listenerClass);
49         }
50     }
51 }
Popular Tags