1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19
20 package org.apache.myfaces.orchestra.viewController;
21
22 import org.apache.myfaces.orchestra.lib.OrchestraException;
23
24 import java.lang.reflect.InvocationTargetException;
25 import java.lang.reflect.Method;
26
27 /**
28 * Invokes ViewController events using reflection.
29 * <p>
30 * If the target bean has a method with any of the following signatures then it
31 * receives the appropriate callback:
32 * <ul>
33 * <li>public void initView()</li>
34 * <li>public void preProcess()</li>
35 * <li>public void preRenderView()</li>
36 * </ul>
37 * <p>
38 * Note that each method here returns false if the target bean does not
39 * have a method with an appropriate signature; this allows this executor to
40 * be "chained" with others.
41 */
42 public class ReflectiveViewControllerExecutor extends AbstractViewControllerExecutor
43 {
44 /**
45 * Helper method to find the method which should get invoked.
46 */
47 protected boolean invokeOnViewController(Object bean, String methodName)
48 {
49 try
50 {
51 Method method = bean.getClass().getMethod(methodName, (Class[]) null); // NON-NLS
52 method.invoke(bean, (Object[]) null);
53 }
54 catch (NoSuchMethodException e)
55 {
56 return false;
57 }
58 catch (IllegalAccessException e)
59 {
60 throw new OrchestraException(e);
61 }
62 catch (InvocationTargetException e)
63 {
64 throw new OrchestraException(e);
65 }
66
67 return true;
68 }
69
70 /* the ViewControllerExecutor interface */
71 public boolean invokeInitView(String beanName, Object bean)
72 {
73 return invokeOnViewController(bean, "initView");
74 }
75
76 public boolean invokePreRenderView(String beanName, Object bean)
77 {
78 return invokeOnViewController(bean, "preRenderView");
79 }
80
81 public boolean invokePreProcess(String beanName, Object bean)
82 {
83 return invokeOnViewController(bean, "preProcess");
84 }
85 }