1 /*
2  * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 only, as
7  * published by the Free Software Foundation.
8  *
9  * This code is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
16  * 2 along with this work; if not, write to the Free Software Foundation,
17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20  * or visit www.oracle.com if you need additional information or have any
21  * questions.
22  */
23 
24 package evalexpr;
25 
26 import java.util.Map;
27 
28 /**
29  * A class loader which loads classes from byte arrays.
30  *
31  * <p><b>This is NOT part of any supported API.
32  * If you write code that depends on this, you do so at your own
33  * risk.  This code and its internal interfaces are subject to change
34  * or deletion without notice.</b></p>
35  * @author Peter von der Ah&eacute;
36  */
37 public class ByteArrayClassLoader extends ClassLoader {
38     /**
39      * Maps binary class names to class files stored as byte arrays.
40      */
41     private Map<String, byte[]> classes;
42 
43     /**
44      * Creates a new instance of ByteArrayClassLoader
45      * @param classes a map from binary class names to class files stored as byte arrays
46      */
ByteArrayClassLoader(Map<String, byte[]> classes)47     public ByteArrayClassLoader(Map<String, byte[]> classes) {
48         this.classes = classes;
49     }
50 
51     @Override
loadClass(String name)52     public Class<?> loadClass(String name) throws ClassNotFoundException {
53         try {
54             return super.loadClass(name);
55         } catch (ClassNotFoundException e) {
56             byte[] classData = classes.get(name);
57             return defineClass(name, classData, 0, classData.length);
58         }
59     }
60 }
61