1 /*
2 * Copyright (c) 2008, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.classfile;
27
28 import java.util.Map;
29
30 import com.sun.tools.classfile.ConstantPool.CONSTANT_Class_info;
31 import com.sun.tools.classfile.ConstantPool.CONSTANT_Double_info;
32 import com.sun.tools.classfile.ConstantPool.CONSTANT_Fieldref_info;
33 import com.sun.tools.classfile.ConstantPool.CONSTANT_Float_info;
34 import com.sun.tools.classfile.ConstantPool.CONSTANT_Integer_info;
35 import com.sun.tools.classfile.ConstantPool.CONSTANT_InterfaceMethodref_info;
36 import com.sun.tools.classfile.ConstantPool.CONSTANT_InvokeDynamic_info;
37 import com.sun.tools.classfile.ConstantPool.CONSTANT_Long_info;
38 import com.sun.tools.classfile.ConstantPool.CONSTANT_MethodHandle_info;
39 import com.sun.tools.classfile.ConstantPool.CONSTANT_MethodType_info;
40 import com.sun.tools.classfile.ConstantPool.CONSTANT_Methodref_info;
41 import com.sun.tools.classfile.ConstantPool.CONSTANT_Module_info;
42 import com.sun.tools.classfile.ConstantPool.CONSTANT_NameAndType_info;
43 import com.sun.tools.classfile.ConstantPool.CONSTANT_Package_info;
44 import com.sun.tools.classfile.ConstantPool.CONSTANT_String_info;
45 import com.sun.tools.classfile.ConstantPool.CONSTANT_Utf8_info;
46 import com.sun.tools.classfile.ConstantPool.CPInfo;
47
48 /**
49 * Rewrites a class file using a map of translations.
50 *
51 * <p><b>This is NOT part of any supported API.
52 * If you write code that depends on this, you do so at your own risk.
53 * This code and its internal interfaces are subject to change or
54 * deletion without notice.</b>
55 */
56 public class ClassTranslator
57 implements ConstantPool.Visitor<ConstantPool.CPInfo,Map<Object,Object>> {
58 /**
59 * Create a new ClassFile from {@code cf}, such that for all entries
60 * {@code k -\> v} in {@code translations},
61 * each occurrence of {@code k} in {@code cf} will be replaced by {@code v}.
62 * in
63 * @param cf the class file to be processed
64 * @param translations the set of translations to be applied
65 * @return a copy of {@code} with the values in {@code translations} substituted
66 */
67 public ClassFile translate(ClassFile cf, Map<Object,Object> translations) {
68 ClassFile cf2 = (ClassFile) translations.get(cf);
69 if (cf2 == null) {
70 ConstantPool constant_pool2 = translate(cf.constant_pool, translations);
71 Field[] fields2 = translate(cf.fields, cf.constant_pool, translations);
72 Method[] methods2 = translateMethods(cf.methods, cf.constant_pool, translations);
73 Attributes attributes2 = translateAttributes(cf.attributes, cf.constant_pool,
74 translations);
75
76 if (constant_pool2 == cf.constant_pool &&
77 fields2 == cf.fields &&
78 methods2 == cf.methods &&
79 attributes2 == cf.attributes)
80 cf2 = cf;
81 else
82 cf2 = new ClassFile(
83 cf.magic,
84 cf.minor_version,
85 cf.major_version,
86 constant_pool2,
87 cf.access_flags,
88 cf.this_class,
89 cf.super_class,
90 cf.interfaces,
91 fields2,
92 methods2,
93 attributes2);
94 translations.put(cf, cf2);
95 }
96 return cf2;
97 }
98
99 ConstantPool translate(ConstantPool cp, Map<Object,Object> translations) {
100 ConstantPool cp2 = (ConstantPool) translations.get(cp);
101 if (cp2 == null) {
102 ConstantPool.CPInfo[] pool2 = new ConstantPool.CPInfo[cp.size()];
103 boolean eq = true;
104 for (int i = 0; i < cp.size(); ) {
105 ConstantPool.CPInfo cpInfo;
106 try {
107 cpInfo = cp.get(i);
108 } catch (ConstantPool.InvalidIndex e) {
109 throw new IllegalStateException(e);
110 }
111 ConstantPool.CPInfo cpInfo2 = translate(cpInfo, translations);
112 eq &= (cpInfo == cpInfo2);
113 pool2[i] = cpInfo2;
114 if (cpInfo.getTag() != cpInfo2.getTag())
115 throw new IllegalStateException();
116 i += cpInfo.size();
117 }
118
119 if (eq)
120 cp2 = cp;
121 else
122 cp2 = new ConstantPool(pool2);
123
124 translations.put(cp, cp2);
125 }
126 return cp2;
127 }
128
129 ConstantPool.CPInfo translate(ConstantPool.CPInfo cpInfo, Map<Object,Object> translations) {
130 ConstantPool.CPInfo cpInfo2 = (ConstantPool.CPInfo) translations.get(cpInfo);
131 if (cpInfo2 == null) {
132 cpInfo2 = cpInfo.accept(this, translations);
133 translations.put(cpInfo, cpInfo2);
134 }
135 return cpInfo2;
136 }
137
138 Field[] translate(Field[] fields, ConstantPool constant_pool, Map<Object,Object> translations) {
139 Field[] fields2 = (Field[]) translations.get(fields);
140 if (fields2 == null) {
141 fields2 = new Field[fields.length];
142 for (int i = 0; i < fields.length; i++)
143 fields2[i] = translate(fields[i], constant_pool, translations);
144 if (equal(fields, fields2))
145 fields2 = fields;
146 translations.put(fields, fields2);
147 }
148 return fields2;
149 }
150
151 Field translate(Field field, ConstantPool constant_pool, Map<Object,Object> translations) {
152 Field field2 = (Field) translations.get(field);
153 if (field2 == null) {
154 Attributes attributes2 = translateAttributes(field.attributes, constant_pool,
155 translations);
156
157 if (attributes2 == field.attributes)
158 field2 = field;
159 else
160 field2 = new Field(
161 field.access_flags,
162 field.name_index,
163 field.descriptor,
164 attributes2);
165 translations.put(field, field2);
166 }
167 return field2;
168 }
169
170 Method[] translateMethods(Method[] methods, ConstantPool constant_pool, Map<Object,Object> translations) {
171 Method[] methods2 = (Method[]) translations.get(methods);
172 if (methods2 == null) {
173 methods2 = new Method[methods.length];
174 for (int i = 0; i < methods.length; i++)
175 methods2[i] = translate(methods[i], constant_pool, translations);
176 if (equal(methods, methods2))
177 methods2 = methods;
178 translations.put(methods, methods2);
179 }
180 return methods2;
181 }
182
183 Method translate(Method method, ConstantPool constant_pool, Map<Object,Object> translations) {
184 Method method2 = (Method) translations.get(method);
185 if (method2 == null) {
186 Attributes attributes2 = translateAttributes(method.attributes, constant_pool,
187 translations);
188
189 if (attributes2 == method.attributes)
190 method2 = method;
191 else
192 method2 = new Method(
193 method.access_flags,
194 method.name_index,
195 method.descriptor,
196 attributes2);
197 translations.put(method, method2);
198 }
199 return method2;
200 }
201
202 Attributes translateAttributes(Attributes attributes,
203 ConstantPool constant_pool, Map<Object,Object> translations) {
204 Attributes attributes2 = (Attributes) translations.get(attributes);
205 if (attributes2 == null) {
206 Attribute[] attrArray2 = new Attribute[attributes.size()];
207 ConstantPool constant_pool2 = translate(constant_pool, translations);
208 boolean attrsEqual = true;
209 for (int i = 0; i < attributes.size(); i++) {
210 Attribute attr = attributes.get(i);
211 Attribute attr2 = translate(attr, translations);
212 if (attr2 != attr)
213 attrsEqual = false;
214 attrArray2[i] = attr2;
215 }
216 if ((constant_pool2 == constant_pool) && attrsEqual)
217 attributes2 = attributes;
218 else
219 attributes2 = new Attributes(constant_pool2, attrArray2);
220 translations.put(attributes, attributes2);
221 }
222 return attributes2;
223 }
224
225 Attribute translate(Attribute attribute, Map<Object,Object> translations) {
226 Attribute attribute2 = (Attribute) translations.get(attribute);
227 if (attribute2 == null) {
228 attribute2 = attribute; // don't support translation within attributes yet
229 // (what about Code attribute)
230 translations.put(attribute, attribute2);
231 }
232 return attribute2;
233 }
234
235 private static <T> boolean equal(T[] a1, T[] a2) {
236 if (a1 == null || a2 == null)
237 return (a1 == a2);
238 if (a1.length != a2.length)
239 return false;
240 for (int i = 0; i < a1.length; i++) {
241 if (a1[i] != a2[i])
242 return false;
243 }
244 return true;
245 }
246
247 @Override
248 public CPInfo visitClass(CONSTANT_Class_info info, Map<Object, Object> translations) {
249 CONSTANT_Class_info info2 = (CONSTANT_Class_info) translations.get(info);
250 if (info2 == null) {
251 ConstantPool cp2 = translate(info.cp, translations);
252 if (cp2 == info.cp)
253 info2 = info;
254 else
255 info2 = new CONSTANT_Class_info(cp2, info.name_index);
256 translations.put(info, info2);
257 }
258 return info;
259 }
260
261 @Override
262 public CPInfo visitDouble(CONSTANT_Double_info info, Map<Object, Object> translations) {
263 CONSTANT_Double_info info2 = (CONSTANT_Double_info) translations.get(info);
264 if (info2 == null) {
265 info2 = info;
266 translations.put(info, info2);
267 }
268 return info;
269 }
270
271 @Override
272 public CPInfo visitFieldref(CONSTANT_Fieldref_info info, Map<Object, Object> translations) {
273 CONSTANT_Fieldref_info info2 = (CONSTANT_Fieldref_info) translations.get(info);
274 if (info2 == null) {
275 ConstantPool cp2 = translate(info.cp, translations);
276 if (cp2 == info.cp)
277 info2 = info;
278 else
279 info2 = new CONSTANT_Fieldref_info(cp2, info.class_index, info.name_and_type_index);
280 translations.put(info, info2);
281 }
282 return info;
283 }
284
285 @Override
286 public CPInfo visitFloat(CONSTANT_Float_info info, Map<Object, Object> translations) {
287 CONSTANT_Float_info info2 = (CONSTANT_Float_info) translations.get(info);
288 if (info2 == null) {
289 info2 = info;
290 translations.put(info, info2);
291 }
292 return info;
293 }
294
295 @Override
296 public CPInfo visitInteger(CONSTANT_Integer_info info, Map<Object, Object> translations) {
297 CONSTANT_Integer_info info2 = (CONSTANT_Integer_info) translations.get(info);
298 if (info2 == null) {
299 info2 = info;
300 translations.put(info, info2);
301 }
302 return info;
303 }
304
305 @Override
306 public CPInfo visitInterfaceMethodref(CONSTANT_InterfaceMethodref_info info, Map<Object, Object> translations) {
307 CONSTANT_InterfaceMethodref_info info2 = (CONSTANT_InterfaceMethodref_info) translations.get(info);
308 if (info2 == null) {
309 ConstantPool cp2 = translate(info.cp, translations);
310 if (cp2 == info.cp)
311 info2 = info;
312 else
313 info2 = new CONSTANT_InterfaceMethodref_info(cp2, info.class_index, info.name_and_type_index);
314 translations.put(info, info2);
315 }
316 return info;
317 }
318
319 @Override
320 public CPInfo visitInvokeDynamic(CONSTANT_InvokeDynamic_info info, Map<Object, Object> translations) {
321 CONSTANT_InvokeDynamic_info info2 = (CONSTANT_InvokeDynamic_info) translations.get(info);
322 if (info2 == null) {
323 ConstantPool cp2 = translate(info.cp, translations);
324 if (cp2 == info.cp) {
325 info2 = info;
326 } else {
327 info2 = new CONSTANT_InvokeDynamic_info(cp2, info.bootstrap_method_attr_index, info.name_and_type_index);
328 }
329 translations.put(info, info2);
330 }
331 return info;
332 }
333
334 @Override
335 public CPInfo visitLong(CONSTANT_Long_info info, Map<Object, Object> translations) {
336 CONSTANT_Long_info info2 = (CONSTANT_Long_info) translations.get(info);
337 if (info2 == null) {
338 info2 = info;
339 translations.put(info, info2);
340 }
341 return info;
342 }
343
344 @Override
345 public CPInfo visitMethodref(CONSTANT_Methodref_info info, Map<Object, Object> translations) {
346 CONSTANT_Methodref_info info2 = (CONSTANT_Methodref_info) translations.get(info);
347 if (info2 == null) {
348 ConstantPool cp2 = translate(info.cp, translations);
349 if (cp2 == info.cp)
350 info2 = info;
351 else
352 info2 = new CONSTANT_Methodref_info(cp2, info.class_index, info.name_and_type_index);
353 translations.put(info, info2);
354 }
355 return info;
356 }
357
358 @Override
359 public CPInfo visitMethodHandle(CONSTANT_MethodHandle_info info, Map<Object, Object> translations) {
360 CONSTANT_MethodHandle_info info2 = (CONSTANT_MethodHandle_info) translations.get(info);
361 if (info2 == null) {
362 ConstantPool cp2 = translate(info.cp, translations);
363 if (cp2 == info.cp) {
364 info2 = info;
365 } else {
366 info2 = new CONSTANT_MethodHandle_info(cp2, info.reference_kind, info.reference_index);
367 }
368 translations.put(info, info2);
369 }
370 return info;
371 }
372
373 @Override
374 public CPInfo visitMethodType(CONSTANT_MethodType_info info, Map<Object, Object> translations) {
375 CONSTANT_MethodType_info info2 = (CONSTANT_MethodType_info) translations.get(info);
376 if (info2 == null) {
377 ConstantPool cp2 = translate(info.cp, translations);
378 if (cp2 == info.cp) {
379 info2 = info;
380 } else {
381 info2 = new CONSTANT_MethodType_info(cp2, info.descriptor_index);
382 }
383 translations.put(info, info2);
384 }
385 return info;
386 }
387
388 @Override
389 public CPInfo visitModule(CONSTANT_Module_info info, Map<Object, Object> translations) {
390 CONSTANT_Module_info info2 = (CONSTANT_Module_info) translations.get(info);
391 if (info2 == null) {
392 ConstantPool cp2 = translate(info.cp, translations);
393 if (cp2 == info.cp)
394 info2 = info;
395 else
396 info2 = new CONSTANT_Module_info(cp2, info.name_index);
397 translations.put(info, info2);
398 }
399 return info;
400 }
401
402 @Override
403 public CPInfo visitNameAndType(CONSTANT_NameAndType_info info, Map<Object, Object> translations) {
404 CONSTANT_NameAndType_info info2 = (CONSTANT_NameAndType_info) translations.get(info);
405 if (info2 == null) {
406 ConstantPool cp2 = translate(info.cp, translations);
407 if (cp2 == info.cp)
408 info2 = info;
409 else
410 info2 = new CONSTANT_NameAndType_info(cp2, info.name_index, info.type_index);
411 translations.put(info, info2);
412 }
413 return info;
414 }
415
416 @Override
417 public CPInfo visitPackage(CONSTANT_Package_info info, Map<Object, Object> translations) {
418 CONSTANT_Package_info info2 = (CONSTANT_Package_info) translations.get(info);
419 if (info2 == null) {
420 ConstantPool cp2 = translate(info.cp, translations);
421 if (cp2 == info.cp)
422 info2 = info;
423 else
424 info2 = new CONSTANT_Package_info(cp2, info.name_index);
425 translations.put(info, info2);
426 }
427 return info;
428 }
429
430 @Override
431 public CPInfo visitString(CONSTANT_String_info info, Map<Object, Object> translations) {
432 CONSTANT_String_info info2 = (CONSTANT_String_info) translations.get(info);
433 if (info2 == null) {
434 ConstantPool cp2 = translate(info.cp, translations);
435 if (cp2 == info.cp)
436 info2 = info;
437 else
438 info2 = new CONSTANT_String_info(cp2, info.string_index);
439 translations.put(info, info2);
440 }
441 return info;
442 }
443
444 @Override
445 public CPInfo visitUtf8(CONSTANT_Utf8_info info, Map<Object, Object> translations) {
446 CONSTANT_Utf8_info info2 = (CONSTANT_Utf8_info) translations.get(info);
447 if (info2 == null) {
448 info2 = info;
449 translations.put(info, info2);
450 }
451 return info;
452 }
453
454 }