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Java > Open Source Codes > org > mule > interceptors > InterceptorStack


1 /*
2  * $Id: InterceptorStack.java 3798 2006-11-04 04:07:14Z aperepel $
3  * --------------------------------------------------------------------------------------
4  * Copyright (c) MuleSource, Inc. All rights reserved. http://www.mulesource.com
5  *
6  * The software in this package is published under the terms of the MuleSource MPL
7  * license, a copy of which has been included with this distribution in the
8  * LICENSE.txt file.
9  */
10
11 package org.mule.interceptors;
12
13 import org.mule.umo.Invocation;
14 import org.mule.umo.UMOException;
15 import org.mule.umo.UMOInterceptor;
16 import org.mule.umo.UMOInterceptorStack;
17 import org.mule.umo.UMOMessage;
18 import org.mule.umo.lifecycle.Disposable;
19 import org.mule.umo.lifecycle.Initialisable;
20 import org.mule.umo.lifecycle.InitialisationException;
21
22 import java.util.Iterator JavaDoc;
23 import java.util.List JavaDoc;
24
25 /**
26  * Maintains a list of interceptors that can be applied to components
27  *
28  * @author <a HREF="mailto:gnt@codehaus.org">Guillaume Nodet</a>
29  * @version $Revision: 3798 $
30  */
31 public class InterceptorStack implements UMOInterceptorStack, Initialisable, Disposable
32 {
33
34     private List JavaDoc interceptors;
35
36     public InterceptorStack()
37     {
38         super();
39     }
40
41     public InterceptorStack(List JavaDoc interceptors)
42     {
43         this.interceptors = interceptors;
44     }
45
46     public UMOMessage intercept(Invocation invocation) throws UMOException
47     {
48         return new Invoc(invocation).execute();
49     }
50
51     private class Invoc extends Invocation
52     {
53         private int cursor = 0;
54         private Invocation invocation;
55
56         public Invoc(Invocation invocation)
57         {
58             super(invocation.getDescriptor(), invocation.getMessage(), invocation);
59             this.invocation = invocation;
60         }
61
62         public UMOMessage execute() throws UMOException
63         {
64             if (interceptors != null && cursor < interceptors.size())
65             {
66                 UMOInterceptor interceptor = (UMOInterceptor)interceptors.get(cursor);
67                 cursor++;
68                 setMessage(interceptor.intercept(this));
69             }
70             else
71             {
72                 invocation.setMessage(getMessage());
73                 setMessage(invocation.execute());
74             }
75             return getMessage();
76         }
77
78     }
79
80     public List JavaDoc getInterceptors()
81     {
82         return interceptors;
83     }
84
85     public void setInterceptors(List JavaDoc interceptors)
86     {
87         this.interceptors = interceptors;
88     }
89
90     public void initialise() throws InitialisationException
91     {
92         for (Iterator JavaDoc it = interceptors.iterator(); it.hasNext();)
93         {
94             UMOInterceptor interceptor = (UMOInterceptor)it.next();
95             if (interceptor instanceof Initialisable)
96             {
97                 ((Initialisable)interceptor).initialise();
98             }
99         }
100     }
101
102     public void dispose()
103     {
104         for (Iterator JavaDoc it = interceptors.iterator(); it.hasNext();)
105         {
106             UMOInterceptor interceptor = (UMOInterceptor)it.next();
107             if (interceptor instanceof Disposable)
108             {
109                 ((Disposable)interceptor).dispose();
110             }
111         }
112     }
113
114 }
115
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