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30 import org.objectweb.asm.FieldVisitor;
31 import org.objectweb.asm.ClassAdapter;
32 import org.objectweb.asm.ClassReader;
33 import org.objectweb.asm.ClassVisitor;
34 import org.objectweb.asm.ClassWriter;
35 import org.objectweb.asm.MethodAdapter;
36 import org.objectweb.asm.MethodVisitor;
37 import org.objectweb.asm.Opcodes;
38 import org.objectweb.asm.Type;
39
40 import java.io.FileOutputStream  ;
41 import java.io.InputStream ;
42 import java.lang.reflect.Method ;
43
44
47 public class Adapt extends ClassLoader {
48
49 protected synchronized Class loadClass(
50 final String name,
51 final boolean resolve) throws ClassNotFoundException
52 {
53 if (name.startsWith("java.")) {
54 System.err.println("Adapt: loading class '" + name
55 + "' without on the fly adaptation");
56 return super.loadClass(name, resolve);
57 } else {
58 System.err.println("Adapt: loading class '" + name
59 + "' with on the fly adaptation");
60 }
61
62 String resource = name.replace('.', '/') + ".class";
64 InputStream is = getResourceAsStream(resource);
65 byte[] b;
66
67 try {
69 ClassReader cr = new ClassReader(is);
70 ClassWriter cw = new ClassWriter(false);
71 ClassVisitor cv = new TraceFieldClassAdapter(cw);
72 cr.accept(cv, false);
73 b = cw.toByteArray();
74 } catch (Exception e) {
75 throw new ClassNotFoundException (name, e);
76 }
77
78 try {
80 FileOutputStream fos = new FileOutputStream (resource + ".adapted");
81 fos.write(b);
82 fos.close();
83 } catch (Exception e) {
84 }
85
86 return defineClass(name, b, 0, b.length);
88 }
89
90 public static void main(final String args[]) throws Exception {
91 ClassLoader loader = new Adapt();
93 Class c = loader.loadClass(args[0]);
94 Method m = c.getMethod("main", new Class [] { String [].class });
97 String [] applicationArgs = new String [args.length - 1];
98 System.arraycopy(args, 1, applicationArgs, 0, applicationArgs.length);
99 m.invoke(null, new Object [] { applicationArgs });
100 }
101 }
102
103 class TraceFieldClassAdapter extends ClassAdapter implements Opcodes {
104
105 private String owner;
106
107 public TraceFieldClassAdapter(final ClassVisitor cv) {
108 super(cv);
109 }
110
111 public void visit(
112 final int version,
113 final int access,
114 final String name,
115 final String signature,
116 final String superName,
117 final String [] interfaces)
118 {
119 owner = name;
120 super.visit(version, access, name, signature, superName, interfaces);
121 }
122
123 public FieldVisitor visitField(
124 final int access,
125 final String name,
126 final String desc,
127 final String signature,
128 final Object value)
129 {
130 FieldVisitor fv = super.visitField(access, name, desc, signature, value);
131 if ((access & ACC_STATIC) == 0) {
132 Type t = Type.getType(desc);
133 int size = t.getSize();
134
135 String gDesc = "()" + desc;
137 MethodVisitor gv = cv.visitMethod(ACC_PRIVATE,
138 "_get" + name,
139 gDesc,
140 null,
141 null);
142 gv.visitFieldInsn(GETSTATIC,
143 "java/lang/System",
144 "err",
145 "Ljava/io/PrintStream;");
146 gv.visitLdcInsn("_get" + name + " called");
147 gv.visitMethodInsn(INVOKEVIRTUAL,
148 "java/io/PrintStream",
149 "println",
150 "(Ljava/lang/String;)V");
151 gv.visitVarInsn(ALOAD, 0);
152 gv.visitFieldInsn(GETFIELD, owner, name, desc);
153 gv.visitInsn(t.getOpcode(IRETURN));
154 gv.visitMaxs(1 + size, 1);
155 gv.visitEnd();
156
157 String sDesc = "(" + desc + ")V";
159 MethodVisitor sv = cv.visitMethod(ACC_PRIVATE,
160 "_set" + name,
161 sDesc,
162 null,
163 null);
164 sv.visitFieldInsn(GETSTATIC,
165 "java/lang/System",
166 "err",
167 "Ljava/io/PrintStream;");
168 sv.visitLdcInsn("_set" + name + " called");
169 sv.visitMethodInsn(INVOKEVIRTUAL,
170 "java/io/PrintStream",
171 "println",
172 "(Ljava/lang/String;)V");
173 sv.visitVarInsn(ALOAD, 0);
174 sv.visitVarInsn(t.getOpcode(ILOAD), 1);
175 sv.visitFieldInsn(PUTFIELD, owner, name, desc);
176 sv.visitInsn(RETURN);
177 sv.visitMaxs(1 + size, 1 + size);
178 sv.visitEnd();
179 }
180 return fv;
181 }
182
183 public MethodVisitor visitMethod(
184 final int access,
185 final String name,
186 final String desc,
187 final String signature,
188 final String [] exceptions)
189 {
190 MethodVisitor mv = cv.visitMethod(access,
191 name,
192 desc,
193 signature,
194 exceptions);
195 return mv == null ? null : new TraceFieldCodeAdapter(mv, owner);
196 }
197 }
198
199 class TraceFieldCodeAdapter extends MethodAdapter implements Opcodes {
200
201 private String owner;
202
203 public TraceFieldCodeAdapter(final MethodVisitor mv, final String owner) {
204 super(mv);
205 this.owner = owner;
206 }
207
208 public void visitFieldInsn(
209 final int opcode,
210 final String owner,
211 final String name,
212 final String desc)
213 {
214 if (owner.equals(this.owner)) {
215 if (opcode == GETFIELD) {
216 String gDesc = "()" + desc;
218 visitMethodInsn(INVOKESPECIAL, owner, "_get" + name, gDesc);
219 return;
220 } else if (opcode == PUTFIELD) {
221 String sDesc = "(" + desc + ")V";
223 visitMethodInsn(INVOKESPECIAL, owner, "_set" + name, sDesc);
224 return;
225 }
226 }
227 super.visitFieldInsn(opcode, owner, name, desc);
228 }
229 }
230 |
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