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1
22 package org.jboss.aop.hook;
23
24 import java.io.File  ;
25 import java.io.FileOutputStream ;
26 import java.io.IOException ;
27
28 import javassist.CannotCompileException;
29 import javassist.ClassPool;
30 import javassist.CtClass;
31 import javassist.CtMethod;
32 import javassist.CtNewMethod;
33 import javassist.LoaderClassPath;
34 import javassist.Modifier;
35 import javassist.NotFoundException;
36
37
42 public class GeneratePluggableInstrumentedClassLoader
43 {
44 private static void declare5(CtClass clazz, CtMethod method) throws NotFoundException, CannotCompileException
45 {
46 method.setName("wrappedDefineClass");
47 CtMethod wrapper = CtNewMethod.make(Modifier.PROTECTED, method.getReturnType(), "defineClass", method.getParameterTypes(), method.getExceptionTypes(), null, clazz);
48
49 String code = "{"
50 + " byte[] newBytes = org.jboss.aop.hook.JDK14TransformerManager.transform($0, $1, $2) ;"
51 + " if (newBytes != (byte[])null) {"
52 + " return wrappedDefineClass($1, newBytes, 0, newBytes.length, $5); "
53 + " } else {"
54 + " return wrappedDefineClass($1, $2, $3, $4, $5); "
55 + " }"
56 + "}";
57 wrapper.setBody(code);
58 clazz.addMethod(wrapper);
59
60 }
61
62
71 public static byte[] getInstrumentedClassLoader()
72 throws NotFoundException, IOException , CannotCompileException
73 {
74 ClassPool classpool = ClassPool.getDefault();
75 classpool = ClassPool.getDefault();
76 ClassLoader cl = Thread.currentThread().getContextClassLoader();
77 classpool.insertClassPath(new LoaderClassPath(cl));
78
79 final CtClass clazz = classpool.get(ClassLoader .class.getName());
80 CtMethod[] methods = clazz.getDeclaredMethods();
81 for (int i = 0; i < methods.length; i++)
82 {
83 if (methods[i].getName().equals("defineClass"))
84 {
85 if (methods[i].getParameterTypes().length == 5
86 && methods[i].getParameterTypes()[1].isArray())
87 {
88 declare5(clazz, methods[i]);
89 }
90 }
91 }
92 return clazz.toBytecode();
93 }
94
95
100 public static void main(final String [] args)
101 {
102 if (args.length != 1)
103 {
104 System.err.println("Usage: java " + GeneratePluggableInstrumentedClassLoader.class.getName() + " <output directory>");
105 System.exit(1);
106 }
107 final String filename = args[0] + File.separatorChar +
108 "java" + File.separatorChar +
109 "lang" + File.separatorChar +
110 "ClassLoader.class";
111 final File file = new File (filename);
112 if (file.exists())
113 {
114 if (!file.canWrite())
115 {
116 System.err.println("Cannot write to existing file: " + file.getAbsolutePath());
117 System.exit(2);
118 }
119 }
120 else
121 {
122 final File dir = file.getParentFile();
123 if (!dir.exists())
124 {
125 dir.mkdirs();
126 }
127 if (!dir.canWrite())
128 {
129 System.err.println("Cannot write to parent directory: " + dir.getAbsolutePath());
130 }
131 }
132
133 final byte[] bytes;
134 try
135 {
136 bytes = getInstrumentedClassLoader();
137 }
138 catch (final Throwable th)
139 {
140 System.err.println("Unexpected exception caught during instrumentation: " + th.getMessage());
141 th.printStackTrace(System.err);
142 System.exit(5);
143 return;
144 }
145
146 try
147 {
148 final FileOutputStream fos = new FileOutputStream (file);
149 fos.write(bytes);
150 fos.close();
151 }
152 catch (final IOException ioe)
153 {
154 System.err.println("Unexpected exception caught while writing class file: " + ioe.getMessage());
155 ioe.printStackTrace(System.err);
156 System.exit(6);
157 }
158 }
159 }
160 |
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