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16 package net.sf.cglib.core;
17
18 import java.io.*;
19 import java.util.*;
20 import org.objectweb.asm.*;
21
22
25 public class ClassEmitter extends ClassAdapter {
26 private ClassInfo classInfo;
27 private Map fieldInfo;
28
29 private static int hookCounter;
30 private MethodVisitor rawStaticInit;
31 private CodeEmitter staticInit;
32 private CodeEmitter staticHook;
33 private Signature staticHookSig;
34
35 public ClassEmitter(ClassVisitor cv) {
36 super(null);
37 setTarget(cv);
38 }
39
40 public ClassEmitter() {
41 super(null);
42 }
43
44 public void setTarget(ClassVisitor cv) {
45 this.cv = cv;
46 fieldInfo = new HashMap();
47
48 staticInit = staticHook = null;
50 staticHookSig = null;
51 }
52
53 synchronized private static int getNextHook() {
54 return ++hookCounter;
55 }
56
57 public ClassInfo getClassInfo() {
58 return classInfo;
59 }
60
61 public void begin_class(int version, final int access, String  className, final Type superType, final Type[] interfaces, String source) {
62 final Type classType = Type.getType("L" + className.replace('.', '/') + ";");
63 classInfo = new ClassInfo() {
64 public Type getType() {
65 return classType;
66 }
67 public Type getSuperType() {
68 return (superType != null) ? superType : Constants.TYPE_OBJECT;
69 }
70 public Type[] getInterfaces() {
71 return interfaces;
72 }
73 public int getModifiers() {
74 return access;
75 }
76 };
77 cv.visit(version,
78 access,
79 classInfo.getType().getInternalName(),
80 null,
81 classInfo.getSuperType().getInternalName(),
82 TypeUtils.toInternalNames(interfaces));
83 if (source != null)
84 cv.visitSource(source, null);
85 init();
86 }
87
88 public CodeEmitter getStaticHook() {
89 if (TypeUtils.isInterface(getAccess())) {
90 throw new IllegalStateException ("static hook is invalid for this class");
91 }
92 if (staticHook == null) {
93 staticHookSig = new Signature("CGLIB$STATICHOOK" + getNextHook(), "()V");
94 staticHook = begin_method(Constants.ACC_STATIC,
95 staticHookSig,
96 null);
97 if (staticInit != null) {
98 staticInit.invoke_static_this(staticHookSig);
99 }
100 }
101 return staticHook;
102 }
103
104 protected void init() {
105 }
106
107 public int getAccess() {
108 return classInfo.getModifiers();
109 }
110
111 public Type getClassType() {
112 return classInfo.getType();
113 }
114
115 public Type getSuperType() {
116 return classInfo.getSuperType();
117 }
118
119 public void end_class() {
120 if (staticHook != null && staticInit == null) {
121 begin_static();
123 }
124 if (staticInit != null) {
125 staticHook.return_value();
126 staticHook.end_method();
127 rawStaticInit.visitInsn(Constants.RETURN);
128 rawStaticInit.visitMaxs(0, 0);
129 staticInit = staticHook = null;
130 staticHookSig = null;
131 }
132 cv.visitEnd();
133 }
134
135 public CodeEmitter begin_method(int access, Signature sig, Type[] exceptions) {
136 if (classInfo == null)
137 throw new IllegalStateException ("classInfo is null! " + this);
138 MethodVisitor v = cv.visitMethod(access,
139 sig.getName(),
140 sig.getDescriptor(),
141 null,
142 TypeUtils.toInternalNames(exceptions));
143 if (sig.equals(Constants.SIG_STATIC) && !TypeUtils.isInterface(getAccess())) {
144 rawStaticInit = v;
145 MethodVisitor wrapped = new MethodAdapter(v) {
146 public void visitMaxs(int maxStack, int maxLocals) {
147 }
149 public void visitInsn(int insn) {
150 if (insn != Constants.RETURN) {
151 super.visitInsn(insn);
152 }
153 }
154 };
155 staticInit = new CodeEmitter(this, wrapped, access, sig, exceptions);
156 if (staticHook == null) {
157 getStaticHook();
159 } else {
160 staticInit.invoke_static_this(staticHookSig);
161 }
162 return staticInit;
163 } else if (sig.equals(staticHookSig)) {
164 return new CodeEmitter(this, v, access, sig, exceptions) {
165 public boolean isStaticHook() {
166 return true;
167 }
168 };
169 } else {
170 return new CodeEmitter(this, v, access, sig, exceptions);
171 }
172 }
173
174 public CodeEmitter begin_static() {
175 return begin_method(Constants.ACC_STATIC, Constants.SIG_STATIC, null);
176 }
177
178 public void declare_field(int access, String name, Type type, Object value) {
179 FieldInfo existing = (FieldInfo)fieldInfo.get(name);
180 FieldInfo info = new FieldInfo(access, name, type, value);
181 if (existing != null) {
182 if (!info.equals(existing)) {
183 throw new IllegalArgumentException ("Field \"" + name + "\" has been declared differently");
184 }
185 } else {
186 fieldInfo.put(name, info);
187 cv.visitField(access, name, type.getDescriptor(), null, value);
188 }
189 }
190
191 boolean isFieldDeclared(String name) {
193 return fieldInfo.get(name) != null;
194 }
195
196 FieldInfo getFieldInfo(String name) {
197 FieldInfo field = (FieldInfo)fieldInfo.get(name);
198 if (field == null) {
199 throw new IllegalArgumentException ("Field " + name + " is not declared in " + getClassType().getClassName());
200 }
201 return field;
202 }
203
204 static class FieldInfo {
205 int access;
206 String name;
207 Type type;
208 Object value;
209
210 public FieldInfo(int access, String name, Type type, Object value) {
211 this.access = access;
212 this.name = name;
213 this.type = type;
214 this.value = value;
215 }
216
217 public boolean equals(Object o) {
218 if (o == null)
219 return false;
220 if (!(o instanceof FieldInfo))
221 return false;
222 FieldInfo other = (FieldInfo)o;
223 if (access != other.access ||
224 !name.equals(other.name) ||
225 !type.equals(other.type)) {
226 return false;
227 }
228 if ((value == null) ^ (other.value == null))
229 return false;
230 if (value != null && !value.equals(other.value))
231 return false;
232 return true;
233 }
234
235 public int hashCode() {
236 return access ^ name.hashCode() ^ type.hashCode() ^ ((value == null) ? 0 : value.hashCode());
237 }
238 }
239
240 public void visit(int version,
241 int access,
242 String name,
243 String signature,
244 String superName,
245 String [] interfaces) {
246 begin_class(version,
247 access,
248 name.replace('/', '.'),
249 TypeUtils.fromInternalName(superName),
250 TypeUtils.fromInternalNames(interfaces),
251 null); }
253
254 public void visitEnd() {
255 end_class();
256 }
257
258 public FieldVisitor visitField(int access,
259 String name,
260 String desc,
261 String signature,
262 Object value) {
263 declare_field(access, name, Type.getType(desc), value);
264 return null; }
266
267 public MethodVisitor visitMethod(int access,
268 String name,
269 String desc,
270 String signature,
271 String [] exceptions) {
272 return begin_method(access,
273 new Signature(name, desc),
274 TypeUtils.fromInternalNames(exceptions));
275 }
276 }
277 |
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