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1
54 package org.logicalcobwebs.cglib.core;
55
56 import java.io.*;
57 import java.util.*;
58 import org.logicalcobwebs.asm.*;
59
60
63 public class ClassEmitter extends ClassAdapter {
64 private static final Signature STATIC_HOOK =
65 TypeUtils.parseSignature("void CGLIB$STATIC_HOOK()");
66 private static final String  STATIC_HOOK_FLAG = "CGLIB$STATIC_HOOK_FLAG";
67
68 private int access;
69 private Type classType;
70 private Type superType;
71 private Map fieldInfo;
72 private boolean seenStatic;
73 private CodeEmitter hook;
74 private boolean ended;
75 private ClassVisitor outer;
76
77 public ClassEmitter(ClassVisitor cv) {
78 super(null);
79 setTarget(cv, this);
80 }
81
82 public ClassEmitter() {
83 super(null);
84 }
85
86 public void setTarget(ClassVisitor cv, ClassVisitor outer) {
87 this.cv = cv;
88 this.outer = outer;
89 fieldInfo = new HashMap();
90 seenStatic = false;
91 hook = null;
92 ended = false;
93 }
94
95 public void begin_class(int access, String className, Type superType, Type[] interfaces, String sourceFile) {
96 this.access = access;
97 this.classType = Type.getType("L" + className.replace('.', '/') + ";");
98 this.superType = (superType != null) ? superType : Constants.TYPE_OBJECT;
99 cv.visit(access,
100 this.classType.getInternalName(),
101 this.superType.getInternalName(),
102 TypeUtils.toInternalNames(interfaces),
103 sourceFile);
104 init();
105 }
106
107 public CodeEmitter getStaticHook() {
108 if (TypeUtils.isInterface(access)) {
109 throw new IllegalStateException ("static hook is invalid for this class");
110 }
111 if (hook == null) {
112 ClassEmitter oe = new ClassEmitter(outer);
113 oe.declare_field(Constants.PRIVATE_FINAL_STATIC, STATIC_HOOK_FLAG, Type.BOOLEAN_TYPE, null, null);
114 CodeEmitter e = oe.begin_method(Constants.ACC_STATIC, STATIC_HOOK, null, null);
115 Label ok = e.make_label();
116 e.getstatic(classType, STATIC_HOOK_FLAG, Type.BOOLEAN_TYPE);
117 e.if_jump(e.EQ, ok);
118 e.return_value();
119 e.mark(ok);
120 e.push(true);
121 e.putstatic(classType, STATIC_HOOK_FLAG, Type.BOOLEAN_TYPE);
122 }
123 return hook;
124 }
125
126 protected void init() {
127 }
128
129 public int getAccess() {
130 return access;
131 }
132
133 public Type getClassType() {
134 return classType;
135 }
136
137 public Type getSuperType() {
138 return superType;
139 }
140
141 public void end_class() {
142 if (seenStatic && hook == null) {
143 getStaticHook(); }
145 if (hook != null) {
146 if (!seenStatic) {
147 CodeVisitor v = outer.visitMethod(Constants.ACC_STATIC,
148 Constants.SIG_STATIC.getName(),
149 Constants.SIG_STATIC.getDescriptor(),
150 null,
151 null);
152 v.visitInsn(Constants.RETURN);
153 v.visitMaxs(0, 0);
154 }
155 ended = true;
156 hook.return_value();
157 hook.end_method();
158 }
159 cv.visitEnd();
160 }
161
162 public CodeEmitter begin_method(int access, Signature sig, Type[] exceptions, Attribute attrs) {
163 CodeVisitor v = cv.visitMethod(access,
164 sig.getName(),
165 sig.getDescriptor(),
166 TypeUtils.toInternalNames(exceptions),
167 attrs);
168 if (sig.equals(STATIC_HOOK)) {
169 hook = new CodeEmitter(this, v, access, sig, exceptions) {
170 public boolean isStaticHook() {
171 return true;
172 }
173 public void visitMaxs(int maxStack, int maxLocals) {
174 if (ended) {
175 super.visitMaxs(maxStack, maxLocals);
176 }
177 }
178 public void visitInsn(int insn) {
179 if (insn != Constants.RETURN || ended) {
180 super.visitInsn(insn);
181 }
182 }
183 };
184 return hook;
185 } else {
186 CodeEmitter e = new CodeEmitter(this, v, access, sig, exceptions);
187 if (sig.equals(Constants.SIG_STATIC) && !TypeUtils.isInterface(this.access)) {
188 seenStatic = true;
189 e.invoke_static_this(STATIC_HOOK);
190 }
191 return e;
192 }
193 }
194
195 public CodeEmitter begin_static() {
196 return begin_method(Constants.ACC_STATIC, Constants.SIG_STATIC, null, null);
197 }
198
199 public void declare_field(int access, String name, Type type, Object value, Attribute attrs) {
200 FieldInfo existing = (FieldInfo)fieldInfo.get(name);
201 FieldInfo info = new FieldInfo(access, name, type, value);
202 if (existing != null) {
203 if (!info.equals(existing)) {
204 throw new IllegalArgumentException ("Field \"" + name + "\" has been declared differently");
205 }
206 } else {
207 fieldInfo.put(name, info);
208 cv.visitField(access, name, type.getDescriptor(), value, attrs);
209 }
210 }
211
212 public void define_attribute(Attribute attrs) {
213 cv.visitAttribute(attrs);
214 }
215
216 boolean isFieldDeclared(String name) {
218 return fieldInfo.get(name) != null;
219 }
220
221 FieldInfo getFieldInfo(String name) {
222 FieldInfo field = (FieldInfo)fieldInfo.get(name);
223 if (field == null) {
224 throw new IllegalArgumentException ("Field " + name + " is not declared in " + classType.getClassName());
225 }
226 return field;
227 }
228
229 static class FieldInfo {
230 int access;
231 String name;
232 Type type;
233 Object value;
234
235 public FieldInfo(int access, String name, Type type, Object value) {
236 this.access = access;
237 this.name = name;
238 this.type = type;
239 this.value = value;
240 }
241
242 public boolean equals(Object o) {
243 if (o == null)
244 return false;
245 if (!(o instanceof FieldInfo))
246 return false;
247 FieldInfo other = (FieldInfo)o;
248 if (access != other.access ||
249 !name.equals(other.name) ||
250 !type.equals(other.type)) {
251 return false;
252 }
253 if ((value == null) ^ (other.value == null))
254 return false;
255 if (value != null && !value.equals(other.value))
256 return false;
257 return true;
258 }
259
260 public int hashCode() {
261 return access ^ name.hashCode() ^ type.hashCode() ^ ((value == null) ? 0 : value.hashCode());
262 }
263 }
264
265 public void visit(int access, String name, String superName, String [] interfaces, String sourceFile) {
266 begin_class(access,
267 name.replace('/', '.'),
268 TypeUtils.fromInternalName(superName),
269 TypeUtils.fromInternalNames(interfaces),
270 sourceFile);
271 }
272
273 public void visitEnd() {
274 end_class();
275 }
276
277 public void visitField(int access, String name, String desc, Object value, Attribute attrs) {
278 declare_field(access, name, Type.getType(desc), value, attrs);
279 }
280
281
283 public CodeVisitor visitMethod(int access, String name, String desc, String [] exceptions, Attribute attrs) {
284 return begin_method(access,
285 new Signature(name, desc),
286 TypeUtils.fromInternalNames(exceptions),
287 attrs);
288 }
289
290 public void visitAttribute(Attribute attrs) {
291 define_attribute(attrs);
292 }
293 }
294 |
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