1 /**********************************************************************
2 * ClassHandler.java
3 * created on 14.08.2004 by netseeker
4 * $Source: /cvsroot/ejoe/EJOE/src/de/netseeker/ejoe/handler/ClassHandler.java,v $
5 * $Date: 2007/11/17 10:57:00 $
6 * $Revision: 1.17 $
7 *
8 * ====================================================================
9 *
10 * Copyright 2005-2006 netseeker aka Michael Manske
11 *
12 * Licensed under the Apache License, Version 2.0 (the "License");
13 * you may not use this file except in compliance with the License.
14 * You may obtain a copy of the License at
15 *
16 * http://www.apache.org/licenses/LICENSE-2.0
17 *
18 * Unless required by applicable law or agreed to in writing, software
19 * distributed under the License is distributed on an "AS IS" BASIS,
20 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
21 * See the License for the specific language governing permissions and
22 * limitations under the License.
23 * ====================================================================
24 *
25 * This file is part of the ejoe framework.
26 * For more information on the author, please see
27 * <http://www.manskes.de/>.
28 *
29 *********************************************************************/
30
31 package de.netseeker.ejoe.handler;
32
33 import java.io.ByteArrayOutputStream;
34 import java.io.IOException;
35 import java.io.InputStream;
36 import java.util.Map;
37 import java.util.logging.Level;
38 import java.util.logging.Logger;
39
40 import de.netseeker.ejoe.EJConstants;
41 import de.netseeker.ejoe.cache.LRUMap;
42 import de.netseeker.ejoe.io.IOUtil;
43
44 /***
45 * A ServerHandler which handles class loader requests. It reads the .class file of the requested class and returns the
46 * content as an ByteArray. A cache is used to store the last thousand returned classes.
47 *
48 * @author netseeker aka Michael Manske
49 * @since 0.3.0
50 */
51 public final class ClassHandler implements ServerHandler
52 {
53 /***
54 *
55 */
56 private static final long serialVersionUID = 1L;
57
58 private static final Logger log = Logger.getLogger( ClassHandler.class.getName() );
59
60 private static final Map _classCache = new LRUMap();
61
62
63
64
65
66
67 public Object handle( Object obj )
68 {
69 byte[] buf = (byte[]) _classCache.get( obj );
70
71 if ( buf == null )
72 {
73 InputStream input = null;
74
75 try
76 {
77 String name = ((String) obj).replaceAll( "//.", "/" );
78 input = ClassHandler.class.getResourceAsStream( '/' + name + ".class" );
79 if ( input != null )
80 {
81 ByteArrayOutputStream bos = new ByteArrayOutputStream( EJConstants.BUFFERED_STREAM_SIZE );
82 byte[] buffer = new byte[EJConstants.BUFFERED_STREAM_SIZE];
83 int count = 0;
84 int n = 0;
85 while ( -1 != (n = input.read( buffer )) )
86 {
87 bos.write( buffer, 0, n );
88 count += n;
89 }
90
91 buf = bos.toByteArray();
92 _classCache.put( obj, buf );
93 }
94 else
95 {
96 throw new RuntimeException( "Class " + obj + "not found." );
97 }
98 }
99 catch ( IOException e )
100 {
101 log.log( Level.SEVERE, "IOException occured while serializing class " + obj + '.', e );
102 throw new RuntimeException( e );
103 }
104 finally
105 {
106 IOUtil.closeQuiet( input );
107 }
108 }
109
110 return buf;
111 }
112 }