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16 package net.sf.cglib.reflect;
17
18 import java.lang.reflect.*;
19 import java.util.*;
20 import net.sf.cglib.core.*;
21 import org.objectweb.asm.ClassVisitor;
22 import org.objectweb.asm.MethodVisitor;
23 import org.objectweb.asm.Type;
24
25 abstract public class MulticastDelegate implements Cloneable  {
26 protected Object [] targets = {};
27
28 protected MulticastDelegate() {
29 }
30
31 public List getTargets() {
32 return new ArrayList(Arrays.asList(targets));
33 }
34
35 abstract public MulticastDelegate add(Object target);
36
37 protected MulticastDelegate addHelper(Object target) {
38 MulticastDelegate copy = newInstance();
39 copy.targets = new Object [targets.length + 1];
40 System.arraycopy(targets, 0, copy.targets, 0, targets.length);
41 copy.targets[targets.length] = target;
42 return copy;
43 }
44
45 public MulticastDelegate remove(Object target) {
46 for (int i = targets.length - 1; i >= 0; i--) {
47 if (targets[i].equals(target)) {
48 MulticastDelegate copy = newInstance();
49 copy.targets = new Object [targets.length - 1];
50 System.arraycopy(targets, 0, copy.targets, 0, i);
51 System.arraycopy(targets, i + 1, copy.targets, i, targets.length - i - 1);
52 return copy;
53 }
54 }
55 return this;
56 }
57
58 abstract public MulticastDelegate newInstance();
59
60 public static MulticastDelegate create(Class iface) {
61 Generator gen = new Generator();
62 gen.setInterface(iface);
63 return gen.create();
64 }
65
66 public static class Generator extends AbstractClassGenerator {
67 private static final Source SOURCE = new Source(MulticastDelegate.class.getName());
68 private static final Type MULTICAST_DELEGATE =
69 TypeUtils.parseType("net.sf.cglib.reflect.MulticastDelegate");
70 private static final Signature NEW_INSTANCE =
71 new Signature("newInstance", MULTICAST_DELEGATE, new Type[0]);
72 private static final Signature ADD_DELEGATE =
73 new Signature("add", MULTICAST_DELEGATE, new Type[]{ Constants.TYPE_OBJECT });
74 private static final Signature ADD_HELPER =
75 new Signature("addHelper", MULTICAST_DELEGATE, new Type[]{ Constants.TYPE_OBJECT });
76
77 private Class iface;
78
79 public Generator() {
80 super(SOURCE);
81 }
82
83 protected ClassLoader getDefaultClassLoader() {
84 return iface.getClassLoader();
85 }
86
87 public void setInterface(Class iface) {
88 this.iface = iface;
89 }
90
91 public MulticastDelegate create() {
92 setNamePrefix(MulticastDelegate.class.getName());
93 return (MulticastDelegate)super.create(iface.getName());
94 }
95
96 public void generateClass(ClassVisitor cv) {
97 final MethodInfo method = ReflectUtils.getMethodInfo(ReflectUtils.findInterfaceMethod(iface));
98
99 ClassEmitter ce = new ClassEmitter(cv);
100 ce.begin_class(Constants.V1_2,
101 Constants.ACC_PUBLIC,
102 getClassName(),
103 MULTICAST_DELEGATE,
104 new Type[]{ Type.getType(iface) },
105 Constants.SOURCE_FILE);
106 EmitUtils.null_constructor(ce);
107
108 emitProxy(ce, method);
110
111 CodeEmitter e = ce.begin_method(Constants.ACC_PUBLIC, NEW_INSTANCE, null);
113 e.new_instance_this();
114 e.dup();
115 e.invoke_constructor_this();
116 e.return_value();
117 e.end_method();
118
119 e = ce.begin_method(Constants.ACC_PUBLIC, ADD_DELEGATE, null);
121 e.load_this();
122 e.load_arg(0);
123 e.checkcast(Type.getType(iface));
124 e.invoke_virtual_this(ADD_HELPER);
125 e.return_value();
126 e.end_method();
127
128 ce.end_class();
129 }
130
131 private void emitProxy(ClassEmitter ce, final MethodInfo method) {
132 final CodeEmitter e = EmitUtils.begin_method(ce, method, Constants.ACC_PUBLIC);
133 Type returnType = method.getSignature().getReturnType();
134 final boolean returns = returnType != Type.VOID_TYPE;
135 Local result = null;
136 if (returns) {
137 result = e.make_local(returnType);
138 e.zero_or_null(returnType);
139 e.store_local(result);
140 }
141 e.load_this();
142 e.super_getfield("targets", Constants.TYPE_OBJECT_ARRAY);
143 final Local result2 = result;
144 EmitUtils.process_array(e, Constants.TYPE_OBJECT_ARRAY, new ProcessArrayCallback() {
145 public void processElement(Type type) {
146 e.checkcast(Type.getType(iface));
147 e.load_args();
148 e.invoke(method);
149 if (returns) {
150 e.store_local(result2);
151 }
152 }
153 });
154 if (returns) {
155 e.load_local(result);
156 }
157 e.return_value();
158 e.end_method();
159 }
160
161 protected Object firstInstance(Class type) {
162 return ((MulticastDelegate)ReflectUtils.newInstance(type)).newInstance();
164 }
165
166 protected Object nextInstance(Object instance) {
167 return ((MulticastDelegate)instance).newInstance();
168 }
169 }
170 }
171 |
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