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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 GenerateInstrumentedClassLoader
43 {
44
45 private static void declare5(CtClass clazz, CtMethod method) throws NotFoundException, CannotCompileException
46 {
47 method.setName("wrappedDefineClass");
48 CtMethod wrapper = CtNewMethod.make(Modifier.PROTECTED, method.getReturnType(), "defineClass", method.getParameterTypes(), method.getExceptionTypes(), null, clazz);
49
50 String code = "{"
51 + " byte[] newBytes = org.jboss.aop.AspectManager.instance().translate($1, $0, $2) ;"
52 + " if (newBytes != (byte[])null) {"
53 + " return wrappedDefineClass($1, newBytes, 0, newBytes.length, $5); "
54 + " } else {"
55 + " return wrappedDefineClass($1, $2, $3, $4, $5); "
56 + " }"
57 + "}";
58 wrapper.setBody(code);
59 clazz.addMethod(wrapper);
60
61 }
62
63
72 public static byte[] getInstrumentedClassLoader()
73 throws NotFoundException, IOException , CannotCompileException
74 {
75 ClassPool classpool = ClassPool.getDefault();
76 classpool = ClassPool.getDefault();
77 ClassLoader cl = Thread.currentThread().getContextClassLoader();
78 classpool.insertClassPath(new LoaderClassPath(cl));
79
80 final CtClass clazz = classpool.get(ClassLoader .class.getName());
81 CtMethod[] methods = clazz.getDeclaredMethods();
82 for (int i = 0; i < methods.length; i++)
83 {
84 if (methods[i].getName().equals("defineClass"))
85 {
86 if (methods[i].getParameterTypes().length == 5
87 && methods[i].getParameterTypes()[1].isArray())
88 {
89 declare5(clazz, methods[i]);
90 }
91 }
92 }
93 return clazz.toBytecode();
94 }
95
96
101 public static void main(final String [] args)
102 {
103 if (args.length != 1)
104 {
105 System.err.println("Usage: java " + GeneratePluggableInstrumentedClassLoader.class.getName() + " <output directory>");
106 System.exit(1);
107 }
108 final String filename = args[0] + File.separatorChar +
109 "java" + File.separatorChar +
110 "lang" + File.separatorChar +
111 "ClassLoader.class";
112 final File file = new File (filename);
113 if (file.exists())
114 {
115 if (!file.canWrite())
116 {
117 System.err.println("Cannot write to existing file: " + file.getAbsolutePath());
118 System.exit(2);
119 }
120 }
121 else
122 {
123 final File dir = file.getParentFile();
124 if (!dir.exists())
125 {
126 dir.mkdirs();
127 }
128 if (!dir.canWrite())
129 {
130 System.err.println("Cannot write to parent directory: " + dir.getAbsolutePath());
131 }
132 }
133
134 final byte[] bytes;
135 try
136 {
137 bytes = getInstrumentedClassLoader();
138 }
139 catch (final Throwable th)
140 {
141 System.err.println("Unexpected exception caught during instrumentation: " + th.getMessage());
142 th.printStackTrace(System.err);
143 System.exit(5);
144 return;
145 }
146
147 try
148 {
149 final FileOutputStream fos = new FileOutputStream (file);
150 fos.write(bytes);
151 fos.close();
152 }
153 catch (final IOException ioe)
154 {
155 System.err.println("Unexpected exception caught while writing class file: " + ioe.getMessage());
156 ioe.printStackTrace(System.err);
157 System.exit(6);
158 }
159 }
160 }
161 |
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