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_NameAndType_info;
42 import com.sun.tools.classfile.ConstantPool.CONSTANT_String_info;
43 import com.sun.tools.classfile.ConstantPool.CONSTANT_Utf8_info;
44 import com.sun.tools.classfile.ConstantPool.CPInfo;
45
46 /**
47 * Rewrites a class file using a map of translations.
48 *
49 * <p><b>This is NOT part of any supported API.
50 * If you write code that depends on this, you do so at your own risk.
51 * This code and its internal interfaces are subject to change or
52 * deletion without notice.</b>
53 */
54 public class ClassTranslator
55 implements ConstantPool.Visitor<ConstantPool.CPInfo,Map<Object,Object>> {
56 /**
57 * Create a new ClassFile from {@code cf}, such that for all entries
58 * {@code k -\> v} in {@code translations},
59 * each occurrence of {@code k} in {@code cf} will be replaced by {@code v}.
60 * in
61 * @param cf the class file to be processed
62 * @param translations the set of translations to be applied
63 * @return a copy of {@code} with the values in {@code translations} substituted
64 */
65 public ClassFile translate(ClassFile cf, Map<Object,Object> translations) {
66 ClassFile cf2 = (ClassFile) translations.get(cf);
67 if (cf2 == null) {
68 ConstantPool constant_pool2 = translate(cf.constant_pool, translations);
69 Field[] fields2 = translate(cf.fields, cf.constant_pool, translations);
70 Method[] methods2 = translateMethods(cf.methods, cf.constant_pool, translations);
71 Attributes attributes2 = translateAttributes(cf.attributes, cf.constant_pool,
72 translations);
73
74 if (constant_pool2 == cf.constant_pool &&
75 fields2 == cf.fields &&
76 methods2 == cf.methods &&
77 attributes2 == cf.attributes)
78 cf2 = cf;
79 else
80 cf2 = new ClassFile(
81 cf.magic,
82 cf.minor_version,
83 cf.major_version,
84 constant_pool2,
85 cf.access_flags,
86 cf.this_class,
87 cf.super_class,
88 cf.interfaces,
89 fields2,
90 methods2,
91 attributes2);
92 translations.put(cf, cf2);
93 }
94 return cf2;
95 }
96
97 ConstantPool translate(ConstantPool cp, Map<Object,Object> translations) {
98 ConstantPool cp2 = (ConstantPool) translations.get(cp);
99 if (cp2 == null) {
100 ConstantPool.CPInfo[] pool2 = new ConstantPool.CPInfo[cp.size()];
101 boolean eq = true;
102 for (int i = 0; i < cp.size(); ) {
103 ConstantPool.CPInfo cpInfo;
104 try {
105 cpInfo = cp.get(i);
106 } catch (ConstantPool.InvalidIndex e) {
107 throw new IllegalStateException(e);
108 }
109 ConstantPool.CPInfo cpInfo2 = translate(cpInfo, translations);
110 eq &= (cpInfo == cpInfo2);
111 pool2[i] = cpInfo2;
112 if (cpInfo.getTag() != cpInfo2.getTag())
113 throw new IllegalStateException();
114 i += cpInfo.size();
115 }
116
117 if (eq)
118 cp2 = cp;
119 else
120 cp2 = new ConstantPool(pool2);
121
122 translations.put(cp, cp2);
123 }
124 return cp2;
125 }
126
127 ConstantPool.CPInfo translate(ConstantPool.CPInfo cpInfo, Map<Object,Object> translations) {
128 ConstantPool.CPInfo cpInfo2 = (ConstantPool.CPInfo) translations.get(cpInfo);
129 if (cpInfo2 == null) {
130 cpInfo2 = cpInfo.accept(this, translations);
131 translations.put(cpInfo, cpInfo2);
132 }
133 return cpInfo2;
134 }
135
136 Field[] translate(Field[] fields, ConstantPool constant_pool, Map<Object,Object> translations) {
137 Field[] fields2 = (Field[]) translations.get(fields);
138 if (fields2 == null) {
139 fields2 = new Field[fields.length];
140 for (int i = 0; i < fields.length; i++)
141 fields2[i] = translate(fields[i], constant_pool, translations);
142 if (equal(fields, fields2))
143 fields2 = fields;
144 translations.put(fields, fields2);
145 }
146 return fields2;
147 }
148
149 Field translate(Field field, ConstantPool constant_pool, Map<Object,Object> translations) {
150 Field field2 = (Field) translations.get(field);
151 if (field2 == null) {
152 Attributes attributes2 = translateAttributes(field.attributes, constant_pool,
153 translations);
154
155 if (attributes2 == field.attributes)
156 field2 = field;
157 else
158 field2 = new Field(
159 field.access_flags,
160 field.name_index,
161 field.descriptor,
162 attributes2);
163 translations.put(field, field2);
164 }
165 return field2;
166 }
167
168 Method[] translateMethods(Method[] methods, ConstantPool constant_pool, Map<Object,Object> translations) {
169 Method[] methods2 = (Method[]) translations.get(methods);
170 if (methods2 == null) {
171 methods2 = new Method[methods.length];
172 for (int i = 0; i < methods.length; i++)
173 methods2[i] = translate(methods[i], constant_pool, translations);
174 if (equal(methods, methods2))
175 methods2 = methods;
176 translations.put(methods, methods2);
177 }
178 return methods2;
179 }
180
181 Method translate(Method method, ConstantPool constant_pool, Map<Object,Object> translations) {
182 Method method2 = (Method) translations.get(method);
183 if (method2 == null) {
184 Attributes attributes2 = translateAttributes(method.attributes, constant_pool,
185 translations);
186
187 if (attributes2 == method.attributes)
188 method2 = method;
189 else
190 method2 = new Method(
191 method.access_flags,
192 method.name_index,
193 method.descriptor,
194 attributes2);
195 translations.put(method, method2);
196 }
197 return method2;
198 }
199
200 Attributes translateAttributes(Attributes attributes,
201 ConstantPool constant_pool, Map<Object,Object> translations) {
202 Attributes attributes2 = (Attributes) translations.get(attributes);
203 if (attributes2 == null) {
204 Attribute[] attrArray2 = new Attribute[attributes.size()];
205 ConstantPool constant_pool2 = translate(constant_pool, translations);
206 boolean attrsEqual = true;
207 for (int i = 0; i < attributes.size(); i++) {
208 Attribute attr = attributes.get(i);
209 Attribute attr2 = translate(attr, translations);
210 if (attr2 != attr)
211 attrsEqual = false;
212 attrArray2[i] = attr2;
213 }
214 if ((constant_pool2 == constant_pool) && attrsEqual)
215 attributes2 = attributes;
216 else
217 attributes2 = new Attributes(constant_pool2, attrArray2);
218 translations.put(attributes, attributes2);
219 }
220 return attributes2;
221 }
222
223 Attribute translate(Attribute attribute, Map<Object,Object> translations) {
224 Attribute attribute2 = (Attribute) translations.get(attribute);
225 if (attribute2 == null) {
226 attribute2 = attribute; // don't support translation within attributes yet
227 // (what about Code attribute)
228 translations.put(attribute, attribute2);
229 }
230 return attribute2;
231 }
232
233 private static <T> boolean equal(T[] a1, T[] a2) {
234 if (a1 == null || a2 == null)
235 return (a1 == a2);
236 if (a1.length != a2.length)
237 return false;
238 for (int i = 0; i < a1.length; i++) {
239 if (a1[i] != a2[i])
240 return false;
241 }
242 return true;
243 }
244
245 public CPInfo visitClass(CONSTANT_Class_info info, Map<Object, Object> translations) {
246 CONSTANT_Class_info info2 = (CONSTANT_Class_info) translations.get(info);
247 if (info2 == null) {
248 ConstantPool cp2 = translate(info.cp, translations);
249 if (cp2 == info.cp)
250 info2 = info;
251 else
252 info2 = new CONSTANT_Class_info(cp2, info.name_index);
253 translations.put(info, info2);
254 }
255 return info;
256 }
257
258 public CPInfo visitDouble(CONSTANT_Double_info info, Map<Object, Object> translations) {
259 CONSTANT_Double_info info2 = (CONSTANT_Double_info) translations.get(info);
260 if (info2 == null) {
261 info2 = info;
262 translations.put(info, info2);
263 }
264 return info;
265 }
266
267 public CPInfo visitFieldref(CONSTANT_Fieldref_info info, Map<Object, Object> translations) {
268 CONSTANT_Fieldref_info info2 = (CONSTANT_Fieldref_info) translations.get(info);
269 if (info2 == null) {
270 ConstantPool cp2 = translate(info.cp, translations);
271 if (cp2 == info.cp)
272 info2 = info;
273 else
274 info2 = new CONSTANT_Fieldref_info(cp2, info.class_index, info.name_and_type_index);
275 translations.put(info, info2);
276 }
277 return info;
278 }
279
280 public CPInfo visitFloat(CONSTANT_Float_info info, Map<Object, Object> translations) {
281 CONSTANT_Float_info info2 = (CONSTANT_Float_info) translations.get(info);
282 if (info2 == null) {
283 info2 = info;
284 translations.put(info, info2);
285 }
286 return info;
287 }
288
289 public CPInfo visitInteger(CONSTANT_Integer_info info, Map<Object, Object> translations) {
290 CONSTANT_Integer_info info2 = (CONSTANT_Integer_info) translations.get(info);
291 if (info2 == null) {
292 info2 = info;
293 translations.put(info, info2);
294 }
295 return info;
296 }
297
298 public CPInfo visitInterfaceMethodref(CONSTANT_InterfaceMethodref_info info, Map<Object, Object> translations) {
299 CONSTANT_InterfaceMethodref_info info2 = (CONSTANT_InterfaceMethodref_info) translations.get(info);
300 if (info2 == null) {
301 ConstantPool cp2 = translate(info.cp, translations);
302 if (cp2 == info.cp)
303 info2 = info;
304 else
305 info2 = new CONSTANT_InterfaceMethodref_info(cp2, info.class_index, info.name_and_type_index);
306 translations.put(info, info2);
307 }
308 return info;
309 }
310
311 public CPInfo visitInvokeDynamic(CONSTANT_InvokeDynamic_info info, Map<Object, Object> translations) {
312 CONSTANT_InvokeDynamic_info info2 = (CONSTANT_InvokeDynamic_info) translations.get(info);
313 if (info2 == null) {
314 ConstantPool cp2 = translate(info.cp, translations);
315 if (cp2 == info.cp) {
316 info2 = info;
317 } else {
318 info2 = new CONSTANT_InvokeDynamic_info(cp2, info.bootstrap_method_attr_index, info.name_and_type_index);
319 }
320 translations.put(info, info2);
321 }
322 return info;
323 }
324
325 public CPInfo visitLong(CONSTANT_Long_info info, Map<Object, Object> translations) {
326 CONSTANT_Long_info info2 = (CONSTANT_Long_info) translations.get(info);
327 if (info2 == null) {
328 info2 = info;
329 translations.put(info, info2);
330 }
331 return info;
332 }
333
334 public CPInfo visitNameAndType(CONSTANT_NameAndType_info info, Map<Object, Object> translations) {
335 CONSTANT_NameAndType_info info2 = (CONSTANT_NameAndType_info) translations.get(info);
336 if (info2 == null) {
337 ConstantPool cp2 = translate(info.cp, translations);
338 if (cp2 == info.cp)
339 info2 = info;
340 else
341 info2 = new CONSTANT_NameAndType_info(cp2, info.name_index, info.type_index);
342 translations.put(info, info2);
343 }
344 return info;
345 }
346
347 public CPInfo visitMethodref(CONSTANT_Methodref_info info, Map<Object, Object> translations) {
348 CONSTANT_Methodref_info info2 = (CONSTANT_Methodref_info) translations.get(info);
349 if (info2 == null) {
350 ConstantPool cp2 = translate(info.cp, translations);
351 if (cp2 == info.cp)
352 info2 = info;
353 else
354 info2 = new CONSTANT_Methodref_info(cp2, info.class_index, info.name_and_type_index);
355 translations.put(info, info2);
356 }
357 return info;
358 }
359
360 public CPInfo visitMethodHandle(CONSTANT_MethodHandle_info info, Map<Object, Object> translations) {
361 CONSTANT_MethodHandle_info info2 = (CONSTANT_MethodHandle_info) translations.get(info);
362 if (info2 == null) {
363 ConstantPool cp2 = translate(info.cp, translations);
364 if (cp2 == info.cp) {
365 info2 = info;
366 } else {
367 info2 = new CONSTANT_MethodHandle_info(cp2, info.reference_kind, info.reference_index);
368 }
369 translations.put(info, info2);
370 }
371 return info;
372 }
373
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 public CPInfo visitString(CONSTANT_String_info info, Map<Object, Object> translations) {
389 CONSTANT_String_info info2 = (CONSTANT_String_info) translations.get(info);
390 if (info2 == null) {
391 ConstantPool cp2 = translate(info.cp, translations);
392 if (cp2 == info.cp)
393 info2 = info;
394 else
395 info2 = new CONSTANT_String_info(cp2, info.string_index);
396 translations.put(info, info2);
397 }
398 return info;
399 }
400
401 public CPInfo visitUtf8(CONSTANT_Utf8_info info, Map<Object, Object> translations) {
402 CONSTANT_Utf8_info info2 = (CONSTANT_Utf8_info) translations.get(info);
403 if (info2 == null) {
404 info2 = info;
405 translations.put(info, info2);
406 }
407 return info;
408 }
409
410 }