1 /*
2  * Copyright (c) 2012, 2013, 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 separate;
25 
26 import java.io.*;
27 
28 public class AttributeInjector implements ClassFilePreprocessor {
29 
30     private String attributeName;
31     private byte[] attributeData;
32 
AttributeInjector(String attributeName, byte[] attributeData)33     public AttributeInjector(String attributeName, byte[] attributeData) {
34         this.attributeName = attributeName;
35         this.attributeData = attributeData;
36     }
37 
preprocess(String name, byte[] cf)38     public byte[] preprocess(String name, byte[] cf) {
39         ClassFile classfile = new ClassFile(cf);
40 
41         short cpIndex = (short)classfile.constant_pool.size();
42 
43         ClassFile.CpUtf8 entry = new ClassFile.CpUtf8();
44         entry.bytes = new byte[attributeName.length()];
45         for (int i = 0; i < attributeName.length(); ++i) {
46             entry.bytes[i] = (byte)attributeName.charAt(i);
47         }
48 
49         classfile.constant_pool.add(entry);
50 
51         ClassFile.Attribute attr = new ClassFile.Attribute();
52         attr.attribute_name_index = cpIndex;
53         attr.info = attributeData;
54 
55         classfile.attributes.add(attr);
56         return classfile.toByteArray();
57     }
58 
59 /*
60     public static void main(String argv[]) throws Exception {
61         File input = new File(argv[0]);
62         byte[] buffer = new byte[(int)input.length()];
63         new FileInputStream(input).read(buffer);
64 
65         ClassFilePreprocessor cfp =
66             new AttributeInjector("RequiresBridges", new byte[0]);
67         byte[] cf = cfp.preprocess(argv[0], buffer);
68         new FileOutputStream(argv[0] + ".mod").write(cf);
69     }
70 */
71 }
72