1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 /*
26 * This file is available under and governed by the GNU General Public
27 * License version 2 only, as published by the Free Software Foundation.
28 * However, the following notice accompanied the original version of this
29 * file:
30 *
31 * ASM: a very small and fast Java bytecode manipulation framework
32 * Copyright (c) 2000-2011 INRIA, France Telecom
33 * All rights reserved.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 * notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 * notice, this list of conditions and the following disclaimer in the
42 * documentation and/or other materials provided with the distribution.
43 * 3. Neither the name of the copyright holders nor the names of its
44 * contributors may be used to endorse or promote products derived from
45 * this software without specific prior written permission.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
48 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
49 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
50 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
51 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
52 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
53 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
54 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
55 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
56 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
57 * THE POSSIBILITY OF SUCH DAMAGE.
58 */
59 package jdk.internal.org.objectweb.asm;
60
61 /**
62 * A {@link ClassVisitor} that generates classes in bytecode form. More
63 * precisely this visitor generates a byte array conforming to the Java class
64 * file format. It can be used alone, to generate a Java class "from scratch",
65 * or with one or more {@link ClassReader ClassReader} and adapter class visitor
66 * to generate a modified class from one or more existing Java classes.
67 *
68 * @author Eric Bruneton
69 */
70 public class ClassWriter extends ClassVisitor {
71
72 /**
73 * Flag to automatically compute the maximum stack size and the maximum
74 * number of local variables of methods. If this flag is set, then the
75 * arguments of the {@link MethodVisitor#visitMaxs visitMaxs} method of the
76 * {@link MethodVisitor} returned by the {@link #visitMethod visitMethod}
77 * method will be ignored, and computed automatically from the signature and
78 * the bytecode of each method.
79 *
80 * @see #ClassWriter(int)
81 */
82 public static final int COMPUTE_MAXS = 1;
83
84 /**
85 * Flag to automatically compute the stack map frames of methods from
86 * scratch. If this flag is set, then the calls to the
87 * {@link MethodVisitor#visitFrame} method are ignored, and the stack map
88 * frames are recomputed from the methods bytecode. The arguments of the
89 * {@link MethodVisitor#visitMaxs visitMaxs} method are also ignored and
90 * recomputed from the bytecode. In other words, computeFrames implies
91 * computeMaxs.
92 *
93 * @see #ClassWriter(int)
94 */
95 public static final int COMPUTE_FRAMES = 2;
96
97 /**
98 * Pseudo access flag to distinguish between the synthetic attribute and the
99 * synthetic access flag.
100 */
101 static final int ACC_SYNTHETIC_ATTRIBUTE = 0x40000;
102
103 /**
104 * Factor to convert from ACC_SYNTHETIC_ATTRIBUTE to Opcode.ACC_SYNTHETIC.
105 */
106 static final int TO_ACC_SYNTHETIC = ACC_SYNTHETIC_ATTRIBUTE
107 / Opcodes.ACC_SYNTHETIC;
108
109 /**
110 * The type of instructions without any argument.
111 */
112 static final int NOARG_INSN = 0;
113
114 /**
115 * The type of instructions with an signed byte argument.
116 */
117 static final int SBYTE_INSN = 1;
118
119 /**
120 * The type of instructions with an signed short argument.
121 */
122 static final int SHORT_INSN = 2;
123
124 /**
125 * The type of instructions with a local variable index argument.
126 */
127 static final int VAR_INSN = 3;
128
129 /**
130 * The type of instructions with an implicit local variable index argument.
131 */
132 static final int IMPLVAR_INSN = 4;
133
134 /**
135 * The type of instructions with a type descriptor argument.
136 */
137 static final int TYPE_INSN = 5;
138
139 /**
140 * The type of field and method invocations instructions.
141 */
142 static final int FIELDORMETH_INSN = 6;
143
144 /**
145 * The type of the INVOKEINTERFACE/INVOKEDYNAMIC instruction.
146 */
147 static final int ITFMETH_INSN = 7;
148
149 /**
150 * The type of the INVOKEDYNAMIC instruction.
151 */
152 static final int INDYMETH_INSN = 8;
153
154 /**
155 * The type of instructions with a 2 bytes bytecode offset label.
156 */
157 static final int LABEL_INSN = 9;
158
159 /**
160 * The type of instructions with a 4 bytes bytecode offset label.
161 */
162 static final int LABELW_INSN = 10;
163
164 /**
165 * The type of the LDC instruction.
166 */
167 static final int LDC_INSN = 11;
168
169 /**
170 * The type of the LDC_W and LDC2_W instructions.
171 */
172 static final int LDCW_INSN = 12;
173
174 /**
175 * The type of the IINC instruction.
176 */
177 static final int IINC_INSN = 13;
178
179 /**
180 * The type of the TABLESWITCH instruction.
181 */
182 static final int TABL_INSN = 14;
183
184 /**
185 * The type of the LOOKUPSWITCH instruction.
186 */
187 static final int LOOK_INSN = 15;
188
189 /**
190 * The type of the MULTIANEWARRAY instruction.
191 */
192 static final int MANA_INSN = 16;
193
194 /**
195 * The type of the WIDE instruction.
196 */
197 static final int WIDE_INSN = 17;
198
199 /**
200 * The instruction types of all JVM opcodes.
201 */
202 static final byte[] TYPE;
203
204 /**
205 * The type of CONSTANT_Class constant pool items.
206 */
207 static final int CLASS = 7;
208
209 /**
210 * The type of CONSTANT_Fieldref constant pool items.
211 */
212 static final int FIELD = 9;
213
214 /**
215 * The type of CONSTANT_Methodref constant pool items.
216 */
217 static final int METH = 10;
218
219 /**
220 * The type of CONSTANT_InterfaceMethodref constant pool items.
221 */
222 static final int IMETH = 11;
223
224 /**
225 * The type of CONSTANT_String constant pool items.
226 */
227 static final int STR = 8;
228
229 /**
230 * The type of CONSTANT_Integer constant pool items.
231 */
232 static final int INT = 3;
233
234 /**
235 * The type of CONSTANT_Float constant pool items.
236 */
237 static final int FLOAT = 4;
238
239 /**
240 * The type of CONSTANT_Long constant pool items.
241 */
242 static final int LONG = 5;
243
244 /**
245 * The type of CONSTANT_Double constant pool items.
246 */
247 static final int DOUBLE = 6;
248
249 /**
250 * The type of CONSTANT_NameAndType constant pool items.
251 */
252 static final int NAME_TYPE = 12;
253
254 /**
255 * The type of CONSTANT_Utf8 constant pool items.
256 */
257 static final int UTF8 = 1;
258
259 /**
260 * The type of CONSTANT_MethodType constant pool items.
261 */
262 static final int MTYPE = 16;
263
264 /**
265 * The type of CONSTANT_MethodHandle constant pool items.
266 */
267 static final int HANDLE = 15;
268
269 /**
270 * The type of CONSTANT_InvokeDynamic constant pool items.
271 */
272 static final int INDY = 18;
273
274 /**
275 * The base value for all CONSTANT_MethodHandle constant pool items.
276 * Internally, ASM store the 9 variations of CONSTANT_MethodHandle into 9
277 * different items.
278 */
279 static final int HANDLE_BASE = 20;
280
281 /**
282 * Normal type Item stored in the ClassWriter {@link ClassWriter#typeTable},
283 * instead of the constant pool, in order to avoid clashes with normal
284 * constant pool items in the ClassWriter constant pool's hash table.
285 */
286 static final int TYPE_NORMAL = 30;
287
288 /**
289 * Uninitialized type Item stored in the ClassWriter
290 * {@link ClassWriter#typeTable}, instead of the constant pool, in order to
291 * avoid clashes with normal constant pool items in the ClassWriter constant
292 * pool's hash table.
293 */
294 static final int TYPE_UNINIT = 31;
295
296 /**
297 * Merged type Item stored in the ClassWriter {@link ClassWriter#typeTable},
298 * instead of the constant pool, in order to avoid clashes with normal
299 * constant pool items in the ClassWriter constant pool's hash table.
300 */
301 static final int TYPE_MERGED = 32;
302
303 /**
304 * The type of BootstrapMethods items. These items are stored in a special
305 * class attribute named BootstrapMethods and not in the constant pool.
306 */
307 static final int BSM = 33;
308
309 /**
310 * The class reader from which this class writer was constructed, if any.
311 */
312 ClassReader cr;
313
314 /**
315 * Minor and major version numbers of the class to be generated.
316 */
317 int version;
318
319 /**
320 * Index of the next item to be added in the constant pool.
321 */
322 int index;
323
324 /**
325 * The constant pool of this class.
326 */
327 final ByteVector pool;
328
329 /**
330 * The constant pool's hash table data.
331 */
332 Item[] items;
333
334 /**
335 * The threshold of the constant pool's hash table.
336 */
337 int threshold;
338
339 /**
340 * A reusable key used to look for items in the {@link #items} hash table.
341 */
342 final Item key;
343
344 /**
345 * A reusable key used to look for items in the {@link #items} hash table.
346 */
347 final Item key2;
348
349 /**
350 * A reusable key used to look for items in the {@link #items} hash table.
351 */
352 final Item key3;
353
354 /**
355 * A reusable key used to look for items in the {@link #items} hash table.
356 */
357 final Item key4;
358
359 /**
360 * A type table used to temporarily store internal names that will not
361 * necessarily be stored in the constant pool. This type table is used by
362 * the control flow and data flow analysis algorithm used to compute stack
363 * map frames from scratch. This array associates to each index <tt>i</tt>
364 * the Item whose index is <tt>i</tt>. All Item objects stored in this array
365 * are also stored in the {@link #items} hash table. These two arrays allow
366 * to retrieve an Item from its index or, conversely, to get the index of an
367 * Item from its value. Each Item stores an internal name in its
368 * {@link Item#strVal1} field.
369 */
370 Item[] typeTable;
371
372 /**
373 * Number of elements in the {@link #typeTable} array.
374 */
375 private short typeCount;
376
377 /**
378 * The access flags of this class.
379 */
380 private int access;
381
382 /**
383 * The constant pool item that contains the internal name of this class.
384 */
385 private int name;
386
387 /**
388 * The internal name of this class.
389 */
390 String thisName;
391
392 /**
393 * The constant pool item that contains the signature of this class.
394 */
395 private int signature;
396
397 /**
398 * The constant pool item that contains the internal name of the super class
399 * of this class.
400 */
401 private int superName;
402
403 /**
404 * Number of interfaces implemented or extended by this class or interface.
405 */
406 private int interfaceCount;
407
408 /**
409 * The interfaces implemented or extended by this class or interface. More
410 * precisely, this array contains the indexes of the constant pool items
411 * that contain the internal names of these interfaces.
412 */
413 private int[] interfaces;
414
415 /**
416 * The index of the constant pool item that contains the name of the source
417 * file from which this class was compiled.
418 */
419 private int sourceFile;
420
421 /**
422 * The SourceDebug attribute of this class.
423 */
424 private ByteVector sourceDebug;
425
426 /**
427 * The constant pool item that contains the name of the enclosing class of
428 * this class.
429 */
430 private int enclosingMethodOwner;
431
432 /**
433 * The constant pool item that contains the name and descriptor of the
434 * enclosing method of this class.
435 */
436 private int enclosingMethod;
437
438 /**
439 * The runtime visible annotations of this class.
440 */
441 private AnnotationWriter anns;
442
443 /**
444 * The runtime invisible annotations of this class.
445 */
446 private AnnotationWriter ianns;
447
448 /**
449 * The runtime visible type annotations of this class.
450 */
451 private AnnotationWriter tanns;
452
453 /**
454 * The runtime invisible type annotations of this class.
455 */
456 private AnnotationWriter itanns;
457
458 /**
459 * The non standard attributes of this class.
460 */
461 private Attribute attrs;
462
463 /**
464 * The number of entries in the InnerClasses attribute.
465 */
466 private int innerClassesCount;
467
468 /**
469 * The InnerClasses attribute.
470 */
471 private ByteVector innerClasses;
472
473 /**
474 * The number of entries in the BootstrapMethods attribute.
475 */
476 int bootstrapMethodsCount;
477
478 /**
479 * The BootstrapMethods attribute.
480 */
481 ByteVector bootstrapMethods;
482
483 /**
484 * The fields of this class. These fields are stored in a linked list of
485 * {@link FieldWriter} objects, linked to each other by their
486 * {@link FieldWriter#fv} field. This field stores the first element of this
487 * list.
488 */
489 FieldWriter firstField;
490
491 /**
492 * The fields of this class. These fields are stored in a linked list of
493 * {@link FieldWriter} objects, linked to each other by their
494 * {@link FieldWriter#fv} field. This field stores the last element of this
495 * list.
496 */
497 FieldWriter lastField;
498
499 /**
500 * The methods of this class. These methods are stored in a linked list of
501 * {@link MethodWriter} objects, linked to each other by their
502 * {@link MethodWriter#mv} field. This field stores the first element of
503 * this list.
504 */
505 MethodWriter firstMethod;
506
507 /**
508 * The methods of this class. These methods are stored in a linked list of
509 * {@link MethodWriter} objects, linked to each other by their
510 * {@link MethodWriter#mv} field. This field stores the last element of this
511 * list.
512 */
513 MethodWriter lastMethod;
514
515 /**
516 * <tt>true</tt> if the maximum stack size and number of local variables
517 * must be automatically computed.
518 */
519 private final boolean computeMaxs;
520
521 /**
522 * <tt>true</tt> if the stack map frames must be recomputed from scratch.
523 */
524 private final boolean computeFrames;
525
526 /**
527 * <tt>true</tt> if the stack map tables of this class are invalid. The
528 * {@link MethodWriter#resizeInstructions} method cannot transform existing
529 * stack map tables, and so produces potentially invalid classes when it is
530 * executed. In this case the class is reread and rewritten with the
531 * {@link #COMPUTE_FRAMES} option (the resizeInstructions method can resize
532 * stack map tables when this option is used).
533 */
534 boolean invalidFrames;
535
536 // ------------------------------------------------------------------------
537 // Static initializer
538 // ------------------------------------------------------------------------
539
540 /**
541 * Computes the instruction types of JVM opcodes.
542 */
543 static {
544 int i;
545 byte[] b = new byte[220];
546 String s = "AAAAAAAAAAAAAAAABCLMMDDDDDEEEEEEEEEEEEEEEEEEEEAAAAAAAADD"
547 + "DDDEEEEEEEEEEEEEEEEEEEEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
548 + "AAAAAAAAAAAAAAAAANAAAAAAAAAAAAAAAAAAAAJJJJJJJJJJJJJJJJDOPAA"
549 + "AAAAGGGGGGGHIFBFAAFFAARQJJKKJJJJJJJJJJJJJJJJJJ";
550 for (i = 0; i < b.length; ++i) {
551 b[i] = (byte) (s.charAt(i) - 'A');
552 }
553 TYPE = b;
554
555 // code to generate the above string
556 //
557 // // SBYTE_INSN instructions
558 // b[Constants.NEWARRAY] = SBYTE_INSN;
559 // b[Constants.BIPUSH] = SBYTE_INSN;
560 //
561 // // SHORT_INSN instructions
562 // b[Constants.SIPUSH] = SHORT_INSN;
563 //
564 // // (IMPL)VAR_INSN instructions
565 // b[Constants.RET] = VAR_INSN;
566 // for (i = Constants.ILOAD; i <= Constants.ALOAD; ++i) {
567 // b[i] = VAR_INSN;
568 // }
569 // for (i = Constants.ISTORE; i <= Constants.ASTORE; ++i) {
570 // b[i] = VAR_INSN;
571 // }
572 // for (i = 26; i <= 45; ++i) { // ILOAD_0 to ALOAD_3
573 // b[i] = IMPLVAR_INSN;
574 // }
575 // for (i = 59; i <= 78; ++i) { // ISTORE_0 to ASTORE_3
576 // b[i] = IMPLVAR_INSN;
577 // }
578 //
579 // // TYPE_INSN instructions
580 // b[Constants.NEW] = TYPE_INSN;
581 // b[Constants.ANEWARRAY] = TYPE_INSN;
582 // b[Constants.CHECKCAST] = TYPE_INSN;
583 // b[Constants.INSTANCEOF] = TYPE_INSN;
584 //
585 // // (Set)FIELDORMETH_INSN instructions
586 // for (i = Constants.GETSTATIC; i <= Constants.INVOKESTATIC; ++i) {
587 // b[i] = FIELDORMETH_INSN;
588 // }
589 // b[Constants.INVOKEINTERFACE] = ITFMETH_INSN;
590 // b[Constants.INVOKEDYNAMIC] = INDYMETH_INSN;
591 //
592 // // LABEL(W)_INSN instructions
593 // for (i = Constants.IFEQ; i <= Constants.JSR; ++i) {
594 // b[i] = LABEL_INSN;
595 // }
596 // b[Constants.IFNULL] = LABEL_INSN;
597 // b[Constants.IFNONNULL] = LABEL_INSN;
598 // b[200] = LABELW_INSN; // GOTO_W
599 // b[201] = LABELW_INSN; // JSR_W
600 // // temporary opcodes used internally by ASM - see Label and
601 // MethodWriter
602 // for (i = 202; i < 220; ++i) {
603 // b[i] = LABEL_INSN;
604 // }
605 //
606 // // LDC(_W) instructions
607 // b[Constants.LDC] = LDC_INSN;
608 // b[19] = LDCW_INSN; // LDC_W
609 // b[20] = LDCW_INSN; // LDC2_W
610 //
611 // // special instructions
612 // b[Constants.IINC] = IINC_INSN;
613 // b[Constants.TABLESWITCH] = TABL_INSN;
614 // b[Constants.LOOKUPSWITCH] = LOOK_INSN;
615 // b[Constants.MULTIANEWARRAY] = MANA_INSN;
616 // b[196] = WIDE_INSN; // WIDE
617 //
618 // for (i = 0; i < b.length; ++i) {
619 // System.err.print((char)('A' + b[i]));
620 // }
621 // System.err.println();
622 }
623
624 // ------------------------------------------------------------------------
625 // Constructor
626 // ------------------------------------------------------------------------
627
628 /**
629 * Constructs a new {@link ClassWriter} object.
630 *
631 * @param flags
632 * option flags that can be used to modify the default behavior
633 * of this class. See {@link #COMPUTE_MAXS},
634 * {@link #COMPUTE_FRAMES}.
635 */
636 public ClassWriter(final int flags) {
637 super(Opcodes.ASM5);
638 index = 1;
639 pool = new ByteVector();
640 items = new Item[256];
641 threshold = (int) (0.75d * items.length);
642 key = new Item();
643 key2 = new Item();
644 key3 = new Item();
645 key4 = new Item();
646 this.computeMaxs = (flags & COMPUTE_MAXS) != 0;
647 this.computeFrames = (flags & COMPUTE_FRAMES) != 0;
648 }
649
650 /**
651 * Constructs a new {@link ClassWriter} object and enables optimizations for
652 * "mostly add" bytecode transformations. These optimizations are the
653 * following:
654 *
655 * <ul>
656 * <li>The constant pool from the original class is copied as is in the new
657 * class, which saves time. New constant pool entries will be added at the
658 * end if necessary, but unused constant pool entries <i>won't be
659 * removed</i>.</li>
660 * <li>Methods that are not transformed are copied as is in the new class,
661 * directly from the original class bytecode (i.e. without emitting visit
662 * events for all the method instructions), which saves a <i>lot</i> of
663 * time. Untransformed methods are detected by the fact that the
664 * {@link ClassReader} receives {@link MethodVisitor} objects that come from
665 * a {@link ClassWriter} (and not from any other {@link ClassVisitor}
666 * instance).</li>
667 * </ul>
668 *
669 * @param classReader
670 * the {@link ClassReader} used to read the original class. It
671 * will be used to copy the entire constant pool from the
672 * original class and also to copy other fragments of original
673 * bytecode where applicable.
674 * @param flags
675 * option flags that can be used to modify the default behavior
676 * of this class. <i>These option flags do not affect methods
677 * that are copied as is in the new class. This means that the
678 * maximum stack size nor the stack frames will be computed for
679 * these methods</i>. See {@link #COMPUTE_MAXS},
680 * {@link #COMPUTE_FRAMES}.
681 */
682 public ClassWriter(final ClassReader classReader, final int flags) {
683 this(flags);
684 classReader.copyPool(this);
685 this.cr = classReader;
686 }
687
688 // ------------------------------------------------------------------------
689 // Implementation of the ClassVisitor abstract class
690 // ------------------------------------------------------------------------
691
692 @Override
693 public final void visit(final int version, final int access,
694 final String name, final String signature, final String superName,
695 final String[] interfaces) {
696 this.version = version;
697 this.access = access;
698 this.name = newClass(name);
699 thisName = name;
700 if (ClassReader.SIGNATURES && signature != null) {
701 this.signature = newUTF8(signature);
702 }
703 this.superName = superName == null ? 0 : newClass(superName);
704 if (interfaces != null && interfaces.length > 0) {
705 interfaceCount = interfaces.length;
706 this.interfaces = new int[interfaceCount];
707 for (int i = 0; i < interfaceCount; ++i) {
708 this.interfaces[i] = newClass(interfaces[i]);
709 }
710 }
711 }
712
713 @Override
714 public final void visitSource(final String file, final String debug) {
715 if (file != null) {
716 sourceFile = newUTF8(file);
717 }
718 if (debug != null) {
719 sourceDebug = new ByteVector().putUTF8(debug);
720 }
721 }
722
723 @Override
724 public final void visitOuterClass(final String owner, final String name,
725 final String desc) {
726 enclosingMethodOwner = newClass(owner);
727 if (name != null && desc != null) {
728 enclosingMethod = newNameType(name, desc);
729 }
730 }
731
732 @Override
733 public final AnnotationVisitor visitAnnotation(final String desc,
734 final boolean visible) {
735 if (!ClassReader.ANNOTATIONS) {
736 return null;
737 }
738 ByteVector bv = new ByteVector();
739 // write type, and reserve space for values count
740 bv.putShort(newUTF8(desc)).putShort(0);
741 AnnotationWriter aw = new AnnotationWriter(this, true, bv, bv, 2);
742 if (visible) {
743 aw.next = anns;
744 anns = aw;
745 } else {
746 aw.next = ianns;
747 ianns = aw;
748 }
749 return aw;
750 }
751
752 @Override
753 public final AnnotationVisitor visitTypeAnnotation(int typeRef,
754 TypePath typePath, final String desc, final boolean visible) {
755 if (!ClassReader.ANNOTATIONS) {
756 return null;
757 }
758 ByteVector bv = new ByteVector();
759 // write target_type and target_info
760 AnnotationWriter.putTarget(typeRef, typePath, bv);
761 // write type, and reserve space for values count
762 bv.putShort(newUTF8(desc)).putShort(0);
763 AnnotationWriter aw = new AnnotationWriter(this, true, bv, bv,
764 bv.length - 2);
765 if (visible) {
766 aw.next = tanns;
767 tanns = aw;
768 } else {
769 aw.next = itanns;
770 itanns = aw;
771 }
772 return aw;
773 }
774
775 @Override
776 public final void visitAttribute(final Attribute attr) {
777 attr.next = attrs;
778 attrs = attr;
779 }
780
781 @Override
782 public final void visitInnerClass(final String name,
783 final String outerName, final String innerName, final int access) {
784 if (innerClasses == null) {
785 innerClasses = new ByteVector();
786 }
787 ++innerClassesCount;
788 innerClasses.putShort(name == null ? 0 : newClass(name));
789 innerClasses.putShort(outerName == null ? 0 : newClass(outerName));
790 innerClasses.putShort(innerName == null ? 0 : newUTF8(innerName));
791 innerClasses.putShort(access);
792 }
793
794 @Override
795 public final FieldVisitor visitField(final int access, final String name,
796 final String desc, final String signature, final Object value) {
797 return new FieldWriter(this, access, name, desc, signature, value);
798 }
799
800 @Override
801 public final MethodVisitor visitMethod(final int access, final String name,
802 final String desc, final String signature, final String[] exceptions) {
803 return new MethodWriter(this, access, name, desc, signature,
804 exceptions, computeMaxs, computeFrames);
805 }
806
807 @Override
808 public final void visitEnd() {
809 }
810
811 // ------------------------------------------------------------------------
812 // Other public methods
813 // ------------------------------------------------------------------------
814
815 /**
816 * Returns the bytecode of the class that was build with this class writer.
817 *
818 * @return the bytecode of the class that was build with this class writer.
819 */
820 public byte[] toByteArray() {
821 if (index > 0xFFFF) {
822 throw new RuntimeException("Class file too large!");
823 }
824 // computes the real size of the bytecode of this class
825 int size = 24 + 2 * interfaceCount;
826 int nbFields = 0;
827 FieldWriter fb = firstField;
828 while (fb != null) {
829 ++nbFields;
830 size += fb.getSize();
831 fb = (FieldWriter) fb.fv;
832 }
833 int nbMethods = 0;
834 MethodWriter mb = firstMethod;
835 while (mb != null) {
836 ++nbMethods;
837 size += mb.getSize();
838 mb = (MethodWriter) mb.mv;
839 }
840 int attributeCount = 0;
841 if (bootstrapMethods != null) {
842 // we put it as first attribute in order to improve a bit
843 // ClassReader.copyBootstrapMethods
844 ++attributeCount;
845 size += 8 + bootstrapMethods.length;
846 newUTF8("BootstrapMethods");
847 }
848 if (ClassReader.SIGNATURES && signature != 0) {
849 ++attributeCount;
850 size += 8;
851 newUTF8("Signature");
852 }
853 if (sourceFile != 0) {
854 ++attributeCount;
855 size += 8;
856 newUTF8("SourceFile");
857 }
858 if (sourceDebug != null) {
859 ++attributeCount;
860 size += sourceDebug.length + 4;
861 newUTF8("SourceDebugExtension");
862 }
863 if (enclosingMethodOwner != 0) {
864 ++attributeCount;
865 size += 10;
866 newUTF8("EnclosingMethod");
867 }
868 if ((access & Opcodes.ACC_DEPRECATED) != 0) {
869 ++attributeCount;
870 size += 6;
871 newUTF8("Deprecated");
872 }
873 if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
874 if ((version & 0xFFFF) < Opcodes.V1_5
875 || (access & ACC_SYNTHETIC_ATTRIBUTE) != 0) {
876 ++attributeCount;
877 size += 6;
878 newUTF8("Synthetic");
879 }
880 }
881 if (innerClasses != null) {
882 ++attributeCount;
883 size += 8 + innerClasses.length;
884 newUTF8("InnerClasses");
885 }
886 if (ClassReader.ANNOTATIONS && anns != null) {
887 ++attributeCount;
888 size += 8 + anns.getSize();
889 newUTF8("RuntimeVisibleAnnotations");
890 }
891 if (ClassReader.ANNOTATIONS && ianns != null) {
892 ++attributeCount;
893 size += 8 + ianns.getSize();
894 newUTF8("RuntimeInvisibleAnnotations");
895 }
896 if (ClassReader.ANNOTATIONS && tanns != null) {
897 ++attributeCount;
898 size += 8 + tanns.getSize();
899 newUTF8("RuntimeVisibleTypeAnnotations");
900 }
901 if (ClassReader.ANNOTATIONS && itanns != null) {
902 ++attributeCount;
903 size += 8 + itanns.getSize();
904 newUTF8("RuntimeInvisibleTypeAnnotations");
905 }
906 if (attrs != null) {
907 attributeCount += attrs.getCount();
908 size += attrs.getSize(this, null, 0, -1, -1);
909 }
910 size += pool.length;
911 // allocates a byte vector of this size, in order to avoid unnecessary
912 // arraycopy operations in the ByteVector.enlarge() method
913 ByteVector out = new ByteVector(size);
914 out.putInt(0xCAFEBABE).putInt(version);
915 out.putShort(index).putByteArray(pool.data, 0, pool.length);
916 int mask = Opcodes.ACC_DEPRECATED | ACC_SYNTHETIC_ATTRIBUTE
917 | ((access & ACC_SYNTHETIC_ATTRIBUTE) / TO_ACC_SYNTHETIC);
918 out.putShort(access & ~mask).putShort(name).putShort(superName);
919 out.putShort(interfaceCount);
920 for (int i = 0; i < interfaceCount; ++i) {
921 out.putShort(interfaces[i]);
922 }
923 out.putShort(nbFields);
924 fb = firstField;
925 while (fb != null) {
926 fb.put(out);
927 fb = (FieldWriter) fb.fv;
928 }
929 out.putShort(nbMethods);
930 mb = firstMethod;
931 while (mb != null) {
932 mb.put(out);
933 mb = (MethodWriter) mb.mv;
934 }
935 out.putShort(attributeCount);
936 if (bootstrapMethods != null) {
937 out.putShort(newUTF8("BootstrapMethods"));
938 out.putInt(bootstrapMethods.length + 2).putShort(
939 bootstrapMethodsCount);
940 out.putByteArray(bootstrapMethods.data, 0, bootstrapMethods.length);
941 }
942 if (ClassReader.SIGNATURES && signature != 0) {
943 out.putShort(newUTF8("Signature")).putInt(2).putShort(signature);
944 }
945 if (sourceFile != 0) {
946 out.putShort(newUTF8("SourceFile")).putInt(2).putShort(sourceFile);
947 }
948 if (sourceDebug != null) {
949 int len = sourceDebug.length - 2;
950 out.putShort(newUTF8("SourceDebugExtension")).putInt(len);
951 out.putByteArray(sourceDebug.data, 2, len);
952 }
953 if (enclosingMethodOwner != 0) {
954 out.putShort(newUTF8("EnclosingMethod")).putInt(4);
955 out.putShort(enclosingMethodOwner).putShort(enclosingMethod);
956 }
957 if ((access & Opcodes.ACC_DEPRECATED) != 0) {
958 out.putShort(newUTF8("Deprecated")).putInt(0);
959 }
960 if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
961 if ((version & 0xFFFF) < Opcodes.V1_5
962 || (access & ACC_SYNTHETIC_ATTRIBUTE) != 0) {
963 out.putShort(newUTF8("Synthetic")).putInt(0);
964 }
965 }
966 if (innerClasses != null) {
967 out.putShort(newUTF8("InnerClasses"));
968 out.putInt(innerClasses.length + 2).putShort(innerClassesCount);
969 out.putByteArray(innerClasses.data, 0, innerClasses.length);
970 }
971 if (ClassReader.ANNOTATIONS && anns != null) {
972 out.putShort(newUTF8("RuntimeVisibleAnnotations"));
973 anns.put(out);
974 }
975 if (ClassReader.ANNOTATIONS && ianns != null) {
976 out.putShort(newUTF8("RuntimeInvisibleAnnotations"));
977 ianns.put(out);
978 }
979 if (ClassReader.ANNOTATIONS && tanns != null) {
980 out.putShort(newUTF8("RuntimeVisibleTypeAnnotations"));
981 tanns.put(out);
982 }
983 if (ClassReader.ANNOTATIONS && itanns != null) {
984 out.putShort(newUTF8("RuntimeInvisibleTypeAnnotations"));
985 itanns.put(out);
986 }
987 if (attrs != null) {
988 attrs.put(this, null, 0, -1, -1, out);
989 }
990 if (invalidFrames) {
991 ClassWriter cw = new ClassWriter(COMPUTE_FRAMES);
992 new ClassReader(out.data).accept(cw, ClassReader.SKIP_FRAMES);
993 return cw.toByteArray();
994 }
995 return out.data;
996 }
997
998 // ------------------------------------------------------------------------
999 // Utility methods: constant pool management
1000 // ------------------------------------------------------------------------
1001
1002 /**
1003 * Adds a number or string constant to the constant pool of the class being
1004 * build. Does nothing if the constant pool already contains a similar item.
1005 *
1006 * @param cst
1007 * the value of the constant to be added to the constant pool.
1008 * This parameter must be an {@link Integer}, a {@link Float}, a
1009 * {@link Long}, a {@link Double}, a {@link String} or a
1010 * {@link Type}.
1011 * @return a new or already existing constant item with the given value.
1012 */
1013 Item newConstItem(final Object cst) {
1014 if (cst instanceof Integer) {
1015 int val = ((Integer) cst).intValue();
1016 return newInteger(val);
1017 } else if (cst instanceof Byte) {
1018 int val = ((Byte) cst).intValue();
1019 return newInteger(val);
1020 } else if (cst instanceof Character) {
1021 int val = ((Character) cst).charValue();
1022 return newInteger(val);
1023 } else if (cst instanceof Short) {
1024 int val = ((Short) cst).intValue();
1025 return newInteger(val);
1026 } else if (cst instanceof Boolean) {
1027 int val = ((Boolean) cst).booleanValue() ? 1 : 0;
1028 return newInteger(val);
1029 } else if (cst instanceof Float) {
1030 float val = ((Float) cst).floatValue();
1031 return newFloat(val);
1032 } else if (cst instanceof Long) {
1033 long val = ((Long) cst).longValue();
1034 return newLong(val);
1035 } else if (cst instanceof Double) {
1036 double val = ((Double) cst).doubleValue();
1037 return newDouble(val);
1038 } else if (cst instanceof String) {
1039 return newString((String) cst);
1040 } else if (cst instanceof Type) {
1041 Type t = (Type) cst;
1042 int s = t.getSort();
1043 if (s == Type.OBJECT) {
1044 return newClassItem(t.getInternalName());
1045 } else if (s == Type.METHOD) {
1046 return newMethodTypeItem(t.getDescriptor());
1047 } else { // s == primitive type or array
1048 return newClassItem(t.getDescriptor());
1049 }
1050 } else if (cst instanceof Handle) {
1051 Handle h = (Handle) cst;
1052 return newHandleItem(h.tag, h.owner, h.name, h.desc);
1053 } else {
1054 throw new IllegalArgumentException("value " + cst);
1055 }
1056 }
1057
1058 /**
1059 * Adds a number or string constant to the constant pool of the class being
1060 * build. Does nothing if the constant pool already contains a similar item.
1061 * <i>This method is intended for {@link Attribute} sub classes, and is
1062 * normally not needed by class generators or adapters.</i>
1063 *
1064 * @param cst
1065 * the value of the constant to be added to the constant pool.
1066 * This parameter must be an {@link Integer}, a {@link Float}, a
1067 * {@link Long}, a {@link Double} or a {@link String}.
1068 * @return the index of a new or already existing constant item with the
1069 * given value.
1070 */
1071 public int newConst(final Object cst) {
1072 return newConstItem(cst).index;
1073 }
1074
1075 /**
1076 * Adds an UTF8 string to the constant pool of the class being build. Does
1077 * nothing if the constant pool already contains a similar item. <i>This
1078 * method is intended for {@link Attribute} sub classes, and is normally not
1079 * needed by class generators or adapters.</i>
1080 *
1081 * @param value
1082 * the String value.
1083 * @return the index of a new or already existing UTF8 item.
1084 */
1085 public int newUTF8(final String value) {
1086 key.set(UTF8, value, null, null);
1087 Item result = get(key);
1088 if (result == null) {
1089 pool.putByte(UTF8).putUTF8(value);
1090 result = new Item(index++, key);
1091 put(result);
1092 }
1093 return result.index;
1094 }
1095
1096 /**
1097 * Adds a class reference to the constant pool of the class being build.
1098 * Does nothing if the constant pool already contains a similar item.
1099 * <i>This method is intended for {@link Attribute} sub classes, and is
1100 * normally not needed by class generators or adapters.</i>
1101 *
1102 * @param value
1103 * the internal name of the class.
1104 * @return a new or already existing class reference item.
1105 */
1106 Item newClassItem(final String value) {
1107 key2.set(CLASS, value, null, null);
1108 Item result = get(key2);
1109 if (result == null) {
1110 pool.put12(CLASS, newUTF8(value));
1111 result = new Item(index++, key2);
1112 put(result);
1113 }
1114 return result;
1115 }
1116
1117 /**
1118 * Adds a class reference to the constant pool of the class being build.
1119 * Does nothing if the constant pool already contains a similar item.
1120 * <i>This method is intended for {@link Attribute} sub classes, and is
1121 * normally not needed by class generators or adapters.</i>
1122 *
1123 * @param value
1124 * the internal name of the class.
1125 * @return the index of a new or already existing class reference item.
1126 */
1127 public int newClass(final String value) {
1128 return newClassItem(value).index;
1129 }
1130
1131 /**
1132 * Adds a method type reference to the constant pool of the class being
1133 * build. Does nothing if the constant pool already contains a similar item.
1134 * <i>This method is intended for {@link Attribute} sub classes, and is
1135 * normally not needed by class generators or adapters.</i>
1136 *
1137 * @param methodDesc
1138 * method descriptor of the method type.
1139 * @return a new or already existing method type reference item.
1140 */
1141 Item newMethodTypeItem(final String methodDesc) {
1142 key2.set(MTYPE, methodDesc, null, null);
1143 Item result = get(key2);
1144 if (result == null) {
1145 pool.put12(MTYPE, newUTF8(methodDesc));
1146 result = new Item(index++, key2);
1147 put(result);
1148 }
1149 return result;
1150 }
1151
1152 /**
1153 * Adds a method type reference to the constant pool of the class being
1154 * build. Does nothing if the constant pool already contains a similar item.
1155 * <i>This method is intended for {@link Attribute} sub classes, and is
1156 * normally not needed by class generators or adapters.</i>
1157 *
1158 * @param methodDesc
1159 * method descriptor of the method type.
1160 * @return the index of a new or already existing method type reference
1161 * item.
1162 */
1163 public int newMethodType(final String methodDesc) {
1164 return newMethodTypeItem(methodDesc).index;
1165 }
1166
1167 /**
1168 * Adds a handle to the constant pool of the class being build. Does nothing
1169 * if the constant pool already contains a similar item. <i>This method is
1170 * intended for {@link Attribute} sub classes, and is normally not needed by
1171 * class generators or adapters.</i>
1172 *
1173 * @param tag
1174 * the kind of this handle. Must be {@link Opcodes#H_GETFIELD},
1175 * {@link Opcodes#H_GETSTATIC}, {@link Opcodes#H_PUTFIELD},
1176 * {@link Opcodes#H_PUTSTATIC}, {@link Opcodes#H_INVOKEVIRTUAL},
1177 * {@link Opcodes#H_INVOKESTATIC},
1178 * {@link Opcodes#H_INVOKESPECIAL},
1179 * {@link Opcodes#H_NEWINVOKESPECIAL} or
1180 * {@link Opcodes#H_INVOKEINTERFACE}.
1181 * @param owner
1182 * the internal name of the field or method owner class.
1183 * @param name
1184 * the name of the field or method.
1185 * @param desc
1186 * the descriptor of the field or method.
1187 * @return a new or an already existing method type reference item.
1188 */
1189 Item newHandleItem(final int tag, final String owner, final String name,
1190 final String desc) {
1191 key4.set(HANDLE_BASE + tag, owner, name, desc);
1192 Item result = get(key4);
1193 if (result == null) {
1194 if (tag <= Opcodes.H_PUTSTATIC) {
1195 put112(HANDLE, tag, newField(owner, name, desc));
1196 } else {
1197 put112(HANDLE,
1198 tag,
1199 newMethod(owner, name, desc,
1200 tag == Opcodes.H_INVOKEINTERFACE));
1201 }
1202 result = new Item(index++, key4);
1203 put(result);
1204 }
1205 return result;
1206 }
1207
1208 /**
1209 * Adds a handle to the constant pool of the class being build. Does nothing
1210 * if the constant pool already contains a similar item. <i>This method is
1211 * intended for {@link Attribute} sub classes, and is normally not needed by
1212 * class generators or adapters.</i>
1213 *
1214 * @param tag
1215 * the kind of this handle. Must be {@link Opcodes#H_GETFIELD},
1216 * {@link Opcodes#H_GETSTATIC}, {@link Opcodes#H_PUTFIELD},
1217 * {@link Opcodes#H_PUTSTATIC}, {@link Opcodes#H_INVOKEVIRTUAL},
1218 * {@link Opcodes#H_INVOKESTATIC},
1219 * {@link Opcodes#H_INVOKESPECIAL},
1220 * {@link Opcodes#H_NEWINVOKESPECIAL} or
1221 * {@link Opcodes#H_INVOKEINTERFACE}.
1222 * @param owner
1223 * the internal name of the field or method owner class.
1224 * @param name
1225 * the name of the field or method.
1226 * @param desc
1227 * the descriptor of the field or method.
1228 * @return the index of a new or already existing method type reference
1229 * item.
1230 */
1231 public int newHandle(final int tag, final String owner, final String name,
1232 final String desc) {
1233 return newHandleItem(tag, owner, name, desc).index;
1234 }
1235
1236 /**
1237 * Adds an invokedynamic reference to the constant pool of the class being
1238 * build. Does nothing if the constant pool already contains a similar item.
1239 * <i>This method is intended for {@link Attribute} sub classes, and is
1240 * normally not needed by class generators or adapters.</i>
1241 *
1242 * @param name
1243 * name of the invoked method.
1244 * @param desc
1245 * descriptor of the invoke method.
1246 * @param bsm
1247 * the bootstrap method.
1248 * @param bsmArgs
1249 * the bootstrap method constant arguments.
1250 *
1251 * @return a new or an already existing invokedynamic type reference item.
1252 */
1253 Item newInvokeDynamicItem(final String name, final String desc,
1254 final Handle bsm, final Object... bsmArgs) {
1255 // cache for performance
1256 ByteVector bootstrapMethods = this.bootstrapMethods;
1257 if (bootstrapMethods == null) {
1258 bootstrapMethods = this.bootstrapMethods = new ByteVector();
1259 }
1260
1261 int position = bootstrapMethods.length; // record current position
1262
1263 int hashCode = bsm.hashCode();
1264 bootstrapMethods.putShort(newHandle(bsm.tag, bsm.owner, bsm.name,
1265 bsm.desc));
1266
1267 int argsLength = bsmArgs.length;
1268 bootstrapMethods.putShort(argsLength);
1269
1270 for (int i = 0; i < argsLength; i++) {
1271 Object bsmArg = bsmArgs[i];
1272 hashCode ^= bsmArg.hashCode();
1273 bootstrapMethods.putShort(newConst(bsmArg));
1274 }
1275
1276 byte[] data = bootstrapMethods.data;
1277 int length = (1 + 1 + argsLength) << 1; // (bsm + argCount + arguments)
1278 hashCode &= 0x7FFFFFFF;
1279 Item result = items[hashCode % items.length];
1280 loop: while (result != null) {
1281 if (result.type != BSM || result.hashCode != hashCode) {
1282 result = result.next;
1283 continue;
1284 }
1285
1286 // because the data encode the size of the argument
1287 // we don't need to test if these size are equals
1288 int resultPosition = result.intVal;
1289 for (int p = 0; p < length; p++) {
1290 if (data[position + p] != data[resultPosition + p]) {
1291 result = result.next;
1292 continue loop;
1293 }
1294 }
1295 break;
1296 }
1297
1298 int bootstrapMethodIndex;
1299 if (result != null) {
1300 bootstrapMethodIndex = result.index;
1301 bootstrapMethods.length = position; // revert to old position
1302 } else {
1303 bootstrapMethodIndex = bootstrapMethodsCount++;
1304 result = new Item(bootstrapMethodIndex);
1305 result.set(position, hashCode);
1306 put(result);
1307 }
1308
1309 // now, create the InvokeDynamic constant
1310 key3.set(name, desc, bootstrapMethodIndex);
1311 result = get(key3);
1312 if (result == null) {
1313 put122(INDY, bootstrapMethodIndex, newNameType(name, desc));
1314 result = new Item(index++, key3);
1315 put(result);
1316 }
1317 return result;
1318 }
1319
1320 /**
1321 * Adds an invokedynamic reference to the constant pool of the class being
1322 * build. Does nothing if the constant pool already contains a similar item.
1323 * <i>This method is intended for {@link Attribute} sub classes, and is
1324 * normally not needed by class generators or adapters.</i>
1325 *
1326 * @param name
1327 * name of the invoked method.
1328 * @param desc
1329 * descriptor of the invoke method.
1330 * @param bsm
1331 * the bootstrap method.
1332 * @param bsmArgs
1333 * the bootstrap method constant arguments.
1334 *
1335 * @return the index of a new or already existing invokedynamic reference
1336 * item.
1337 */
1338 public int newInvokeDynamic(final String name, final String desc,
1339 final Handle bsm, final Object... bsmArgs) {
1340 return newInvokeDynamicItem(name, desc, bsm, bsmArgs).index;
1341 }
1342
1343 /**
1344 * Adds a field reference to the constant pool of the class being build.
1345 * Does nothing if the constant pool already contains a similar item.
1346 *
1347 * @param owner
1348 * the internal name of the field's owner class.
1349 * @param name
1350 * the field's name.
1351 * @param desc
1352 * the field's descriptor.
1353 * @return a new or already existing field reference item.
1354 */
1355 Item newFieldItem(final String owner, final String name, final String desc) {
1356 key3.set(FIELD, owner, name, desc);
1357 Item result = get(key3);
1358 if (result == null) {
1359 put122(FIELD, newClass(owner), newNameType(name, desc));
1360 result = new Item(index++, key3);
1361 put(result);
1362 }
1363 return result;
1364 }
1365
1366 /**
1367 * Adds a field reference to the constant pool of the class being build.
1368 * Does nothing if the constant pool already contains a similar item.
1369 * <i>This method is intended for {@link Attribute} sub classes, and is
1370 * normally not needed by class generators or adapters.</i>
1371 *
1372 * @param owner
1373 * the internal name of the field's owner class.
1374 * @param name
1375 * the field's name.
1376 * @param desc
1377 * the field's descriptor.
1378 * @return the index of a new or already existing field reference item.
1379 */
1380 public int newField(final String owner, final String name, final String desc) {
1381 return newFieldItem(owner, name, desc).index;
1382 }
1383
1384 /**
1385 * Adds a method reference to the constant pool of the class being build.
1386 * Does nothing if the constant pool already contains a similar item.
1387 *
1388 * @param owner
1389 * the internal name of the method's owner class.
1390 * @param name
1391 * the method's name.
1392 * @param desc
1393 * the method's descriptor.
1394 * @param itf
1395 * <tt>true</tt> if <tt>owner</tt> is an interface.
1396 * @return a new or already existing method reference item.
1397 */
1398 Item newMethodItem(final String owner, final String name,
1399 final String desc, final boolean itf) {
1400 int type = itf ? IMETH : METH;
1401 key3.set(type, owner, name, desc);
1402 Item result = get(key3);
1403 if (result == null) {
1404 put122(type, newClass(owner), newNameType(name, desc));
1405 result = new Item(index++, key3);
1406 put(result);
1407 }
1408 return result;
1409 }
1410
1411 /**
1412 * Adds a method reference to the constant pool of the class being build.
1413 * Does nothing if the constant pool already contains a similar item.
1414 * <i>This method is intended for {@link Attribute} sub classes, and is
1415 * normally not needed by class generators or adapters.</i>
1416 *
1417 * @param owner
1418 * the internal name of the method's owner class.
1419 * @param name
1420 * the method's name.
1421 * @param desc
1422 * the method's descriptor.
1423 * @param itf
1424 * <tt>true</tt> if <tt>owner</tt> is an interface.
1425 * @return the index of a new or already existing method reference item.
1426 */
1427 public int newMethod(final String owner, final String name,
1428 final String desc, final boolean itf) {
1429 return newMethodItem(owner, name, desc, itf).index;
1430 }
1431
1432 /**
1433 * Adds an integer to the constant pool of the class being build. Does
1434 * nothing if the constant pool already contains a similar item.
1435 *
1436 * @param value
1437 * the int value.
1438 * @return a new or already existing int item.
1439 */
1440 Item newInteger(final int value) {
1441 key.set(value);
1442 Item result = get(key);
1443 if (result == null) {
1444 pool.putByte(INT).putInt(value);
1445 result = new Item(index++, key);
1446 put(result);
1447 }
1448 return result;
1449 }
1450
1451 /**
1452 * Adds a float to the constant pool of the class being build. Does nothing
1453 * if the constant pool already contains a similar item.
1454 *
1455 * @param value
1456 * the float value.
1457 * @return a new or already existing float item.
1458 */
1459 Item newFloat(final float value) {
1460 key.set(value);
1461 Item result = get(key);
1462 if (result == null) {
1463 pool.putByte(FLOAT).putInt(key.intVal);
1464 result = new Item(index++, key);
1465 put(result);
1466 }
1467 return result;
1468 }
1469
1470 /**
1471 * Adds a long to the constant pool of the class being build. Does nothing
1472 * if the constant pool already contains a similar item.
1473 *
1474 * @param value
1475 * the long value.
1476 * @return a new or already existing long item.
1477 */
1478 Item newLong(final long value) {
1479 key.set(value);
1480 Item result = get(key);
1481 if (result == null) {
1482 pool.putByte(LONG).putLong(value);
1483 result = new Item(index, key);
1484 index += 2;
1485 put(result);
1486 }
1487 return result;
1488 }
1489
1490 /**
1491 * Adds a double to the constant pool of the class being build. Does nothing
1492 * if the constant pool already contains a similar item.
1493 *
1494 * @param value
1495 * the double value.
1496 * @return a new or already existing double item.
1497 */
1498 Item newDouble(final double value) {
1499 key.set(value);
1500 Item result = get(key);
1501 if (result == null) {
1502 pool.putByte(DOUBLE).putLong(key.longVal);
1503 result = new Item(index, key);
1504 index += 2;
1505 put(result);
1506 }
1507 return result;
1508 }
1509
1510 /**
1511 * Adds a string to the constant pool of the class being build. Does nothing
1512 * if the constant pool already contains a similar item.
1513 *
1514 * @param value
1515 * the String value.
1516 * @return a new or already existing string item.
1517 */
1518 private Item newString(final String value) {
1519 key2.set(STR, value, null, null);
1520 Item result = get(key2);
1521 if (result == null) {
1522 pool.put12(STR, newUTF8(value));
1523 result = new Item(index++, key2);
1524 put(result);
1525 }
1526 return result;
1527 }
1528
1529 /**
1530 * Adds a name and type to the constant pool of the class being build. Does
1531 * nothing if the constant pool already contains a similar item. <i>This
1532 * method is intended for {@link Attribute} sub classes, and is normally not
1533 * needed by class generators or adapters.</i>
1534 *
1535 * @param name
1536 * a name.
1537 * @param desc
1538 * a type descriptor.
1539 * @return the index of a new or already existing name and type item.
1540 */
1541 public int newNameType(final String name, final String desc) {
1542 return newNameTypeItem(name, desc).index;
1543 }
1544
1545 /**
1546 * Adds a name and type to the constant pool of the class being build. Does
1547 * nothing if the constant pool already contains a similar item.
1548 *
1549 * @param name
1550 * a name.
1551 * @param desc
1552 * a type descriptor.
1553 * @return a new or already existing name and type item.
1554 */
1555 Item newNameTypeItem(final String name, final String desc) {
1556 key2.set(NAME_TYPE, name, desc, null);
1557 Item result = get(key2);
1558 if (result == null) {
1559 put122(NAME_TYPE, newUTF8(name), newUTF8(desc));
1560 result = new Item(index++, key2);
1561 put(result);
1562 }
1563 return result;
1564 }
1565
1566 /**
1567 * Adds the given internal name to {@link #typeTable} and returns its index.
1568 * Does nothing if the type table already contains this internal name.
1569 *
1570 * @param type
1571 * the internal name to be added to the type table.
1572 * @return the index of this internal name in the type table.
1573 */
1574 int addType(final String type) {
1575 key.set(TYPE_NORMAL, type, null, null);
1576 Item result = get(key);
1577 if (result == null) {
1578 result = addType(key);
1579 }
1580 return result.index;
1581 }
1582
1583 /**
1584 * Adds the given "uninitialized" type to {@link #typeTable} and returns its
1585 * index. This method is used for UNINITIALIZED types, made of an internal
1586 * name and a bytecode offset.
1587 *
1588 * @param type
1589 * the internal name to be added to the type table.
1590 * @param offset
1591 * the bytecode offset of the NEW instruction that created this
1592 * UNINITIALIZED type value.
1593 * @return the index of this internal name in the type table.
1594 */
1595 int addUninitializedType(final String type, final int offset) {
1596 key.type = TYPE_UNINIT;
1597 key.intVal = offset;
1598 key.strVal1 = type;
1599 key.hashCode = 0x7FFFFFFF & (TYPE_UNINIT + type.hashCode() + offset);
1600 Item result = get(key);
1601 if (result == null) {
1602 result = addType(key);
1603 }
1604 return result.index;
1605 }
1606
1607 /**
1608 * Adds the given Item to {@link #typeTable}.
1609 *
1610 * @param item
1611 * the value to be added to the type table.
1612 * @return the added Item, which a new Item instance with the same value as
1613 * the given Item.
1614 */
1615 private Item addType(final Item item) {
1616 ++typeCount;
1617 Item result = new Item(typeCount, key);
1618 put(result);
1619 if (typeTable == null) {
1620 typeTable = new Item[16];
1621 }
1622 if (typeCount == typeTable.length) {
1623 Item[] newTable = new Item[2 * typeTable.length];
1624 System.arraycopy(typeTable, 0, newTable, 0, typeTable.length);
1625 typeTable = newTable;
1626 }
1627 typeTable[typeCount] = result;
1628 return result;
1629 }
1630
1631 /**
1632 * Returns the index of the common super type of the two given types. This
1633 * method calls {@link #getCommonSuperClass} and caches the result in the
1634 * {@link #items} hash table to speedup future calls with the same
1635 * parameters.
1636 *
1637 * @param type1
1638 * index of an internal name in {@link #typeTable}.
1639 * @param type2
1640 * index of an internal name in {@link #typeTable}.
1641 * @return the index of the common super type of the two given types.
1642 */
1643 int getMergedType(final int type1, final int type2) {
1644 key2.type = TYPE_MERGED;
1645 key2.longVal = type1 | (((long) type2) << 32);
1646 key2.hashCode = 0x7FFFFFFF & (TYPE_MERGED + type1 + type2);
1647 Item result = get(key2);
1648 if (result == null) {
1649 String t = typeTable[type1].strVal1;
1650 String u = typeTable[type2].strVal1;
1651 key2.intVal = addType(getCommonSuperClass(t, u));
1652 result = new Item((short) 0, key2);
1653 put(result);
1654 }
1655 return result.intVal;
1656 }
1657
1658 /**
1659 * Returns the common super type of the two given types. The default
1660 * implementation of this method <i>loads</i> the two given classes and uses
1661 * the java.lang.Class methods to find the common super class. It can be
1662 * overridden to compute this common super type in other ways, in particular
1663 * without actually loading any class, or to take into account the class
1664 * that is currently being generated by this ClassWriter, which can of
1665 * course not be loaded since it is under construction.
1666 *
1667 * @param type1
1668 * the internal name of a class.
1669 * @param type2
1670 * the internal name of another class.
1671 * @return the internal name of the common super class of the two given
1672 * classes.
1673 */
1674 protected String getCommonSuperClass(final String type1, final String type2) {
1675 Class<?> c, d;
1676 ClassLoader classLoader = getClass().getClassLoader();
1677 try {
1678 c = Class.forName(type1.replace('/', '.'), false, classLoader);
1679 d = Class.forName(type2.replace('/', '.'), false, classLoader);
1680 } catch (Exception e) {
1681 throw new RuntimeException(e.toString());
1682 }
1683 if (c.isAssignableFrom(d)) {
1684 return type1;
1685 }
1686 if (d.isAssignableFrom(c)) {
1687 return type2;
1688 }
1689 if (c.isInterface() || d.isInterface()) {
1690 return "java/lang/Object";
1691 } else {
1692 do {
1693 c = c.getSuperclass();
1694 } while (!c.isAssignableFrom(d));
1695 return c.getName().replace('.', '/');
1696 }
1697 }
1698
1699 /**
1700 * Returns the constant pool's hash table item which is equal to the given
1701 * item.
1702 *
1703 * @param key
1704 * a constant pool item.
1705 * @return the constant pool's hash table item which is equal to the given
1706 * item, or <tt>null</tt> if there is no such item.
1707 */
1708 private Item get(final Item key) {
1709 Item i = items[key.hashCode % items.length];
1710 while (i != null && (i.type != key.type || !key.isEqualTo(i))) {
1711 i = i.next;
1712 }
1713 return i;
1714 }
1715
1716 /**
1717 * Puts the given item in the constant pool's hash table. The hash table
1718 * <i>must</i> not already contains this item.
1719 *
1720 * @param i
1721 * the item to be added to the constant pool's hash table.
1722 */
1723 private void put(final Item i) {
1724 if (index + typeCount > threshold) {
1725 int ll = items.length;
1726 int nl = ll * 2 + 1;
1727 Item[] newItems = new Item[nl];
1728 for (int l = ll - 1; l >= 0; --l) {
1729 Item j = items[l];
1730 while (j != null) {
1731 int index = j.hashCode % newItems.length;
1732 Item k = j.next;
1733 j.next = newItems[index];
1734 newItems[index] = j;
1735 j = k;
1736 }
1737 }
1738 items = newItems;
1739 threshold = (int) (nl * 0.75);
1740 }
1741 int index = i.hashCode % items.length;
1742 i.next = items[index];
1743 items[index] = i;
1744 }
1745
1746 /**
1747 * Puts one byte and two shorts into the constant pool.
1748 *
1749 * @param b
1750 * a byte.
1751 * @param s1
1752 * a short.
1753 * @param s2
1754 * another short.
1755 */
1756 private void put122(final int b, final int s1, final int s2) {
1757 pool.put12(b, s1).putShort(s2);
1758 }
1759
1760 /**
1761 * Puts two bytes and one short into the constant pool.
1762 *
1763 * @param b1
1764 * a byte.
1765 * @param b2
1766 * another byte.
1767 * @param s
1768 * a short.
1769 */
1770 private void put112(final int b1, final int b2, final int s) {
1771 pool.put11(b1, b2).putShort(s);
1772 }
1773 }