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1
16 package net.sf.cglib.transform;
17
18 import net.sf.cglib.core.CodeGenerationException;
19 import net.sf.cglib.core.ClassGenerator;
20 import net.sf.cglib.core.DebuggingClassWriter;
21 import org.objectweb.asm.ClassReader;
22 import org.objectweb.asm.ClassWriter;
23 import org.objectweb.asm.util.*;
24 import org.objectweb.asm.Attribute;
25
26 import java.io.IOException  ;
27
28 abstract public class AbstractClassLoader extends ClassLoader {
29 private ClassFilter filter;
30 private ClassLoader classPath;
31 private static java.security.ProtectionDomain DOMAIN ;
32
33 static{
34
35 DOMAIN = (java.security.ProtectionDomain )
36 java.security.AccessController.doPrivileged(
37 new java.security.PrivilegedAction () {
38 public Object run() {
39 return AbstractClassLoader.class.getProtectionDomain();
40 }
41 });
42 }
43
44 protected AbstractClassLoader(ClassLoader parent, ClassLoader classPath, ClassFilter filter) {
45 super(parent);
46 this.filter = filter;
47 this.classPath = classPath;
48 }
49
50 public Class loadClass(String name) throws ClassNotFoundException {
51
52 Class loaded = findLoadedClass(name);
53
54 if( loaded != null ){
55 if( loaded.getClassLoader() == this ){
56 return loaded;
57 } }
59
60 if (!filter.accept(name)) {
61 return super.loadClass(name);
62 }
63 ClassReader r;
64 try {
65
66 java.io.InputStream is = classPath.getResourceAsStream(
67 name.replace('.','/') + ".class"
68 );
69
70 if (is == null) {
71
72 throw new ClassNotFoundException (name);
73
74 }
75 try {
76
77 r = new ClassReader(is);
78
79 } finally {
80
81 is.close();
82
83 }
84 } catch (IOException e) {
85 throw new ClassNotFoundException (name + ":" + e.getMessage());
86 }
87
88 try {
89 ClassWriter w = new DebuggingClassWriter(true);
90 getGenerator(r).generateClass( w );
91 byte[] b = w.toByteArray();
92 Class c = super.defineClass(name, b, 0, b.length, DOMAIN);
93 postProcess(c);
94 return c;
95 } catch (RuntimeException e) {
96 throw e;
97 } catch (Error e) {
98 throw e;
99 } catch (Exception e) {
100 throw new CodeGenerationException(e);
101 }
102 }
103
104 protected ClassGenerator getGenerator(ClassReader r) {
105 return new ClassReaderGenerator(r, attributes(), skipDebug());
106 }
107
108 protected boolean skipDebug() {
109 return false;
110 }
111
112 protected Attribute[] attributes() {
113 return null;
114 }
115
116 protected void postProcess(Class c) {
117 }
118 }
119 |
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