Java > Open Source Codes > net > sf > retrotranslator > runtime > asm > ClassWriter


1 /***
2  * ASM: a very small and fast Java bytecode manipulation framework
3  * Copyright (c) 2000-2005 INRIA, France Telecom
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  * notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  * notice, this list of conditions and the following disclaimer in the
13  * documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the copyright holders nor the names of its
15  * contributors may be used to endorse or promote products derived from
16  * this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
28  * THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 package net.sf.retrotranslator.runtime.asm;
31
32 /**
33  * A {@link ClassVisitor} that generates classes in bytecode form. More
34  * precisely this visitor generates a byte array conforming to the Java class
35  * file format. It can be used alone, to generate a Java class "from scratch",
36  * or with one or more {@link ClassReader ClassReader} and adapter class visitor
37  * to generate a modified class from one or more existing Java classes.
38  *
39  * @author Eric Bruneton
40  */
41 public class ClassWriter implements ClassVisitor {
42
43     /**
44      * The type of instructions without any argument.
45      */
46     final static int NOARG_INSN = 0;
47
48     /**
49      * The type of instructions with an signed byte argument.
50      */
51     final static int SBYTE_INSN = 1;
52
53     /**
54      * The type of instructions with an signed short argument.
55      */
56     final static int SHORT_INSN = 2;
57
58     /**
59      * The type of instructions with a local variable index argument.
60      */
61     final static int VAR_INSN = 3;
62
63     /**
64      * The type of instructions with an implicit local variable index argument.
65      */
66     final static int IMPLVAR_INSN = 4;
67
68     /**
69      * The type of instructions with a type descriptor argument.
70      */
71     final static int TYPE_INSN = 5;
72
73     /**
74      * The type of field and method invocations instructions.
75      */
76     final static int FIELDORMETH_INSN = 6;
77
78     /**
79      * The type of the INVOKEINTERFACE instruction.
80      */
81     final static int ITFMETH_INSN = 7;
82
83     /**
84      * The type of instructions with a 2 bytes bytecode offset label.
85      */
86     final static int LABEL_INSN = 8;
87
88     /**
89      * The type of instructions with a 4 bytes bytecode offset label.
90      */
91     final static int LABELW_INSN = 9;
92
93     /**
94      * The type of the LDC instruction.
95      */
96     final static int LDC_INSN = 10;
97
98     /**
99      * The type of the LDC_W and LDC2_W instructions.
100      */
101     final static int LDCW_INSN = 11;
102
103     /**
104      * The type of the IINC instruction.
105      */
106     final static int IINC_INSN = 12;
107
108     /**
109      * The type of the TABLESWITCH instruction.
110      */
111     final static int TABL_INSN = 13;
112
113     /**
114      * The type of the LOOKUPSWITCH instruction.
115      */
116     final static int LOOK_INSN = 14;
117
118     /**
119      * The type of the MULTIANEWARRAY instruction.
120      */
121     final static int MANA_INSN = 15;
122
123     /**
124      * The type of the WIDE instruction.
125      */
126     final static int WIDE_INSN = 16;
127
128     /**
129      * The instruction types of all JVM opcodes.
130      */
131     static byte[] TYPE;
132
133     /**
134      * The type of CONSTANT_Class constant pool items.
135      */
136     final static int CLASS = 7;
137
138     /**
139      * The type of CONSTANT_Fieldref constant pool items.
140      */
141     final static int FIELD = 9;
142
143     /**
144      * The type of CONSTANT_Methodref constant pool items.
145      */
146     final static int METH = 10;
147
148     /**
149      * The type of CONSTANT_InterfaceMethodref constant pool items.
150      */
151     final static int IMETH = 11;
152
153     /**
154      * The type of CONSTANT_String constant pool items.
155      */
156     final static int STR = 8;
157
158     /**
159      * The type of CONSTANT_Integer constant pool items.
160      */
161     final static int INT = 3;
162
163     /**
164      * The type of CONSTANT_Float constant pool items.
165      */
166     final static int FLOAT = 4;
167
168     /**
169      * The type of CONSTANT_Long constant pool items.
170      */
171     final static int LONG = 5;
172
173     /**
174      * The type of CONSTANT_Double constant pool items.
175      */
176     final static int DOUBLE = 6;
177
178     /**
179      * The type of CONSTANT_NameAndType constant pool items.
180      */
181     final static int NAME_TYPE = 12;
182
183     /**
184      * The type of CONSTANT_Utf8 constant pool items.
185      */
186     final static int UTF8 = 1;
187
188     /**
189      * The class reader from which this class writer was constructed, if any.
190      */
191     ClassReader cr;
192
193     /**
194      * Minor and major version numbers of the class to be generated.
195      */
196     int version;
197
198     /**
199      * Index of the next item to be added in the constant pool.
200      */
201     int index;
202
203     /**
204      * The constant pool of this class.
205      */
206     ByteVector pool;
207
208     /**
209      * The constant pool's hash table data.
210      */
211     Item[] items;
212
213     /**
214      * The threshold of the constant pool's hash table.
215      */
216     int threshold;
217
218     /**
219      * A reusable key used to look for items in the hash {@link #items items}.
220      */
221     Item key;
222
223     /**
224      * A reusable key used to look for items in the hash {@link #items items}.
225      */
226     Item key2;
227
228     /**
229      * A reusable key used to look for items in the hash {@link #items items}.
230      */
231     Item key3;
232
233     /**
234      * The access flags of this class.
235      */
236     private int access;
237
238     /**
239      * The constant pool item that contains the internal name of this class.
240      */
241     private int name;
242
243     /**
244      * The constant pool item that contains the signature of this class.
245      */
246     private int signature;
247
248     /**
249      * The constant pool item that contains the internal name of the super class
250      * of this class.
251      */
252     private int superName;
253
254     /**
255      * Number of interfaces implemented or extended by this class or interface.
256      */
257     private int interfaceCount;
258
259     /**
260      * The interfaces implemented or extended by this class or interface. More
261      * precisely, this array contains the indexes of the constant pool items
262      * that contain the internal names of these interfaces.
263      */
264     private int[] interfaces;
265
266     /**
267      * The index of the constant pool item that contains the name of the source
268      * file from which this class was compiled.
269      */
270     private int sourceFile;
271
272     /**
273      * The SourceDebug attribute of this class.
274      */
275     private ByteVector sourceDebug;
276
277     /**
278      * The constant pool item that contains the name of the enclosing class of
279      * this class.
280      */
281     private int enclosingMethodOwner;
282
283     /**
284      * The constant pool item that contains the name and descriptor of the
285      * enclosing method of this class.
286      */
287     private int enclosingMethod;
288
289     /**
290      * The runtime visible annotations of this class.
291      */
292     private AnnotationWriter anns;
293
294     /**
295      * The runtime invisible annotations of this class.
296      */
297     private AnnotationWriter ianns;
298
299     /**
300      * The non standard attributes of this class.
301      */
302     private Attribute attrs;
303
304     /**
305      * The number of entries in the InnerClasses attribute.
306      */
307     private int innerClassesCount;
308
309     /**
310      * The InnerClasses attribute.
311      */
312     private ByteVector innerClasses;
313
314     /**
315      * The fields of this class. These fields are stored in a linked list of
316      * {@link FieldWriter} objects, linked to each other by their
317      * {@link FieldWriter#next} field. This field stores the first element of
318      * this list.
319      */
320     FieldWriter firstField;
321
322     /**
323      * The fields of this class. These fields are stored in a linked list of
324      * {@link FieldWriter} objects, linked to each other by their
325      * {@link FieldWriter#next} field. This field stores the last element of
326      * this list.
327      */
328     FieldWriter lastField;
329
330     /**
331      * The methods of this class. These methods are stored in a linked list of
332      * {@link MethodWriter} objects, linked to each other by their
333      * {@link MethodWriter#next} field. This field stores the first element of
334      * this list.
335      */
336     MethodWriter firstMethod;
337
338     /**
339      * The methods of this class. These methods are stored in a linked list of
340      * {@link MethodWriter} objects, linked to each other by their
341      * {@link MethodWriter#next} field. This field stores the last element of
342      * this list.
343      */
344     MethodWriter lastMethod;
345
346     /**
347      * <tt>true</tt> if the maximum stack size and number of local variables
348      * must be automatically computed.
349      */
350     private boolean computeMaxs;
351
352     // ------------------------------------------------------------------------
353 // Static initializer
354 // ------------------------------------------------------------------------
355
356     /**
357      * Computes the instruction types of JVM opcodes.
358      */
359     static {
360         int i;
361         byte[] b = new byte[220];
362         String s = "AAAAAAAAAAAAAAAABCKLLDDDDDEEEEEEEEEEEEEEEEEEEEAAAAAAAADD"
363                 + "DDDEEEEEEEEEEEEEEEEEEEEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
364                 + "AAAAAAAAAAAAAAAAAMAAAAAAAAAAAAAAAAAAAAIIIIIIIIIIIIIIIIDNOAA"
365                 + "AAAAGGGGGGGHAFBFAAFFAAQPIIJJIIIIIIIIIIIIIIIIII";
366         for (i = 0; i < b.length; ++i) {
367             b[i] = (byte) (s.charAt(i) - 'A');
368         }
369         TYPE = b;
370
371         // code to generate the above string
372 //
373 // // SBYTE_INSN instructions
374 // b[Constants.NEWARRAY] = SBYTE_INSN;
375 // b[Constants.BIPUSH] = SBYTE_INSN;
376 //
377 // // SHORT_INSN instructions
378 // b[Constants.SIPUSH] = SHORT_INSN;
379 //
380 // // (IMPL)VAR_INSN instructions
381 // b[Constants.RET] = VAR_INSN;
382 // for (i = Constants.ILOAD; i <= Constants.ALOAD; ++i) {
383 // b[i] = VAR_INSN;
384 // }
385 // for (i = Constants.ISTORE; i <= Constants.ASTORE; ++i) {
386 // b[i] = VAR_INSN;
387 // }
388 // for (i = 26; i <= 45; ++i) { // ILOAD_0 to ALOAD_3
389 // b[i] = IMPLVAR_INSN;
390 // }
391 // for (i = 59; i <= 78; ++i) { // ISTORE_0 to ASTORE_3
392 // b[i] = IMPLVAR_INSN;
393 // }
394 //
395 // // TYPE_INSN instructions
396 // b[Constants.NEW] = TYPE_INSN;
397 // b[Constants.ANEWARRAY] = TYPE_INSN;
398 // b[Constants.CHECKCAST] = TYPE_INSN;
399 // b[Constants.INSTANCEOF] = TYPE_INSN;
400 //
401 // // (Set)FIELDORMETH_INSN instructions
402 // for (i = Constants.GETSTATIC; i <= Constants.INVOKESTATIC; ++i) {
403 // b[i] = FIELDORMETH_INSN;
404 // }
405 // b[Constants.INVOKEINTERFACE] = ITFMETH_INSN;
406 //
407 // // LABEL(W)_INSN instructions
408 // for (i = Constants.IFEQ; i <= Constants.JSR; ++i) {
409 // b[i] = LABEL_INSN;
410 // }
411 // b[Constants.IFNULL] = LABEL_INSN;
412 // b[Constants.IFNONNULL] = LABEL_INSN;
413 // b[200] = LABELW_INSN; // GOTO_W
414 // b[201] = LABELW_INSN; // JSR_W
415 // // temporary opcodes used internally by ASM - see Label and
416 // MethodWriter
417 // for (i = 202; i < 220; ++i) {
418 // b[i] = LABEL_INSN;
419 // }
420 //
421 // // LDC(_W) instructions
422 // b[Constants.LDC] = LDC_INSN;
423 // b[19] = LDCW_INSN; // LDC_W
424 // b[20] = LDCW_INSN; // LDC2_W
425 //
426 // // special instructions
427 // b[Constants.IINC] = IINC_INSN;
428 // b[Constants.TABLESWITCH] = TABL_INSN;
429 // b[Constants.LOOKUPSWITCH] = LOOK_INSN;
430 // b[Constants.MULTIANEWARRAY] = MANA_INSN;
431 // b[196] = WIDE_INSN; // WIDE
432 //
433 // for (i = 0; i < b.length; ++i) {
434 // System.err.print((char)('A' + b[i]));
435 // }
436 // System.err.println();
437 }
438
439     // ------------------------------------------------------------------------
440 // Constructor
441 // ------------------------------------------------------------------------
442
443     /**
444      * Constructs a new {@link ClassWriter ClassWriter} object.
445      *
446      * @param computeMaxs <tt>true</tt> if the maximum stack size and the
447      * maximum number of local variables must be automatically computed.
448      * If this flag is <tt>true</tt>, then the arguments of the
449      * {@link MethodVisitor#visitMaxs visitMaxs} method of the
450      * {@link MethodVisitor} returned by the
451      * {@link #visitMethod visitMethod} method will be ignored, and
452      * computed automatically from the signature and the bytecode of each
453      * method.
454      */
455     public ClassWriter(final boolean computeMaxs) {
456         this(computeMaxs, false);
457     }
458
459     /**
460      * Constructs a new {@link ClassWriter} object.
461      *
462      * @param computeMaxs <tt>true</tt> if the maximum stack size and the
463      * maximum number of local variables must be automatically computed.
464      * If this flag is <tt>true</tt>, then the arguments of the
465      * {@link MethodVisitor#visitMaxs visitMaxs} method of the
466      * {@link MethodVisitor} returned by the
467      * {@link #visitMethod visitMethod} method will be ignored, and
468      * computed automatically from the signature and the bytecode of each
469      * method.
470      * @param skipUnknownAttributes <b>Deprecated</b>. The value of this
471      * parameter is ignored.
472      */
473     public ClassWriter(
474         final boolean computeMaxs,
475         final boolean skipUnknownAttributes)
476     {
477         index = 1;
478         pool = new ByteVector();
479         items = new Item[256];
480         threshold = (int) (0.75d * items.length);
481         key = new Item();
482         key2 = new Item();
483         key3 = new Item();
484         this.computeMaxs = computeMaxs;
485     }
486
487     /**
488      * Constructs a new {@link ClassWriter} object and enables optimizations for
489      * "mostly add" bytecode transformations. These optimizations are the
490      * following:
491      *
492      * <ul> <li>The constant pool from the original class is copied as is in
493      * the new class, which saves time. New constant pool entries will be added
494      * at the end if necessary, but unused constant pool entries <i>won't be
495      * removed</i>.</li> <li>Methods that are not transformed are copied as
496      * is in the new class, directly from the original class bytecode (i.e.
497      * without emitting visit events for all the method instructions), which
498      * saves a <i>lot</i> of time. Untransformed methods are detected by the
499      * fact that the {@link ClassReader} receives {@link MethodVisitor} objects
500      * that come from a {@link ClassWriter} (and not from a custom
501      * {@link ClassAdapter} or any other {@link ClassVisitor} instance).</li>
502      * </ul>
503      *
504      * @param classReader the {@link ClassReader} used to read the original
505      * class. It will be used to copy the entire constant pool from the
506      * original class and also to copy other fragments of original
507      * bytecode where applicable.
508      * @param computeMaxs <tt>true</tt> if the maximum stack size and the
509      * maximum number of local variables must be automatically computed.
510      * If this flag is <tt>true</tt>, then the arguments of the
511      * {@link MethodVisitor#visitMaxs visitMaxs} method of the
512      * {@link MethodVisitor} returned by the
513      * {@link #visitMethod visitMethod} method will be ignored, and
514      * computed automatically from the signature and the bytecode of each
515      * method.
516      */
517     public ClassWriter(
518         final ClassReader classReader,
519         final boolean computeMaxs)
520     {
521         this(computeMaxs, false);
522         classReader.copyPool(this);
523         this.cr = classReader;
524     }
525
526     // ------------------------------------------------------------------------
527 // Implementation of the ClassVisitor interface
528 // ------------------------------------------------------------------------
529
530     public void visit(
531         final int version,
532         final int access,
533         final String name,
534         final String signature,
535         final String superName,
536         final String [] interfaces)
537     {
538         this.version = version;
539         this.access = access;
540         this.name = newClass(name);
541         if (signature != null) {
542             this.signature = newUTF8(signature);
543         }
544         this.superName = superName == null ? 0 : newClass(superName);
545         if (interfaces != null && interfaces.length > 0) {
546             interfaceCount = interfaces.length;
547             this.interfaces = new int[interfaceCount];
548             for (int i = 0; i < interfaceCount; ++i) {
549                 this.interfaces[i] = newClass(interfaces[i]);
550             }
551         }
552     }
553
554     public void visitSource(final String file, final String debug) {
555         if (file != null) {
556             sourceFile = newUTF8(file);
557         }
558         if (debug != null) {
559             sourceDebug = new ByteVector().putUTF8(debug);
560         }
561     }
562
563     public void visitOuterClass(
564         final String owner,
565         final String name,
566         final String desc)
567     {
568         enclosingMethodOwner = newClass(owner);
569         if (name != null && desc != null) {
570             enclosingMethod = newNameType(name, desc);
571         }
572     }
573
574     public AnnotationVisitor visitAnnotation(String desc, boolean visible) {
575         ByteVector bv = new ByteVector();
576         // write type, and reserve space for values count
577 bv.putShort(newUTF8(desc)).putShort(0);
578         AnnotationWriter aw = new AnnotationWriter(this, true, bv, bv, 2);
579         if (visible) {
580             aw.next = anns;
581             anns = aw;
582         } else {
583             aw.next = ianns;
584             ianns = aw;
585         }
586         return aw;
587     }
588
589     public void visitAttribute(final Attribute attr) {
590         attr.next = attrs;
591         attrs = attr;
592     }
593
594     public void visitInnerClass(
595         final String name,
596         final String outerName,
597         final String innerName,
598         final int access)
599     {
600         if (innerClasses == null) {
601             innerClasses = new ByteVector();
602         }
603         ++innerClassesCount;
604         innerClasses.putShort(name == null ? 0 : newClass(name));
605         innerClasses.putShort(outerName == null ? 0 : newClass(outerName));
606         innerClasses.putShort(innerName == null ? 0 : newUTF8(innerName));
607         innerClasses.putShort(access);
608     }
609
610     public FieldVisitor visitField(
611         final int access,
612         final String name,
613         final String desc,
614         final String signature,
615         final Object value)
616     {
617         return new FieldWriter(this, access, name, desc, signature, value);
618     }
619
620     public MethodVisitor visitMethod(
621         final int access,
622         final String name,
623         final String desc,
624         final String signature,
625         final String [] exceptions)
626     {
627         return new MethodWriter(this,
628                 access,
629                 name,
630                 desc,
631                 signature,
632                 exceptions,
633                 computeMaxs);
634     }
635
636     public void visitEnd() {
637     }
638
639     // ------------------------------------------------------------------------
640 // Other public methods
641 // ------------------------------------------------------------------------
642
643     /**
644      * Returns the bytecode of the class that was build with this class writer.
645      *
646      * @return the bytecode of the class that was build with this class writer.
647      */
648     public byte[] toByteArray() {
649         return toByteArray(false);
650     }
651
652     public byte[] toByteArray(boolean dropTigerFlags) {
653         // computes the real size of the bytecode of this class
654 int size = 24 + 2 * interfaceCount;
655         int nbFields = 0;
656         FieldWriter fb = firstField;
657         while (fb != null) {
658             ++nbFields;
659             size += fb.getSize();
660             fb = fb.next;
661         }
662         int nbMethods = 0;
663         MethodWriter mb = firstMethod;
664         while (mb != null) {
665             ++nbMethods;
666             size += mb.getSize();
667             mb = mb.next;
668         }
669         int attributeCount = 0;
670         if (signature != 0) {
671             ++attributeCount;
672             size += 8;
673             newUTF8("Signature");
674         }
675         if (sourceFile != 0) {
676             ++attributeCount;
677             size += 8;
678             newUTF8("SourceFile");
679         }
680         if (sourceDebug != null) {
681             ++attributeCount;
682             size += sourceDebug.length + 4;
683             newUTF8("SourceDebugExtension");
684         }
685         if (enclosingMethodOwner != 0) {
686             ++attributeCount;
687             size += 10;
688             newUTF8("EnclosingMethod");
689         }
690         if ((access & Opcodes.ACC_DEPRECATED) != 0) {
691             ++attributeCount;
692             size += 6;
693             newUTF8("Deprecated");
694         }
695         if ((access & Opcodes.ACC_SYNTHETIC) != 0
696                 && (version & 0xffff) < Opcodes.V1_5)
697         {
698             ++attributeCount;
699             size += 6;
700             newUTF8("Synthetic");
701         }
702         if (version == Opcodes.V1_4) {
703             if ((access & Opcodes.ACC_ANNOTATION) != 0) {
704                 ++attributeCount;
705                 size += 6;
706                 newUTF8("Annotation");
707             }
708             if ((access & Opcodes.ACC_ENUM) != 0) {
709                 ++attributeCount;
710                 size += 6;
711                 newUTF8("Enum");
712             }
713         }
714         if (innerClasses != null) {
715             ++attributeCount;
716             size += 8 + innerClasses.length;
717             newUTF8("InnerClasses");
718         }
719         if (anns != null) {
720             ++attributeCount;
721             size += 8 + anns.getSize();
722             newUTF8("RuntimeVisibleAnnotations");
723         }
724         if (ianns != null) {
725             ++attributeCount;
726             size += 8 + ianns.getSize();
727             newUTF8("RuntimeInvisibleAnnotations");
728         }
729         if (attrs != null) {
730             attributeCount += attrs.getCount();
731             size += attrs.getSize(this, null, 0, -1, -1);
732         }
733         size += pool.length;
734         // allocates a byte vector of this size, in order to avoid unnecessary
735 // arraycopy operations in the ByteVector.enlarge() method
736 ByteVector out = new ByteVector(size);
737         out.putInt(0xCAFEBABE).putInt(version);
738         out.putShort(index).putByteArray(pool.data, 0, pool.length);
739         int modifiers = access;
740         if (dropTigerFlags) {
741             modifiers &= ~(Opcodes.ACC_SYNTHETIC | Opcodes.ACC_ANNOTATION | Opcodes.ACC_ENUM);
742         }
743         out.putShort(modifiers).putShort(name).putShort(superName);
744         out.putShort(interfaceCount);
745         for (int i = 0; i < interfaceCount; ++i) {
746             out.putShort(interfaces[i]);
747         }
748         out.putShort(nbFields);
749         fb = firstField;
750         while (fb != null) {
751             fb.put(out, dropTigerFlags);
752             fb = fb.next;
753         }
754         out.putShort(nbMethods);
755         mb = firstMethod;
756         while (mb != null) {
757             mb.put(out, dropTigerFlags);
758             mb = mb.next;
759         }
760         out.putShort(attributeCount);
761         if (signature != 0) {
762             out.putShort(newUTF8("Signature")).putInt(2).putShort(signature);
763         }
764         if (sourceFile != 0) {
765             out.putShort(newUTF8("SourceFile")).putInt(2).putShort(sourceFile);
766         }
767         if (sourceDebug != null) {
768             int len = sourceDebug.length - 2;
769             out.putShort(newUTF8("SourceDebugExtension")).putInt(len);
770             out.putByteArray(sourceDebug.data, 2, len);
771         }
772         if (enclosingMethodOwner != 0) {
773             out.putShort(newUTF8("EnclosingMethod")).putInt(4);
774             out.putShort(enclosingMethodOwner).putShort(enclosingMethod);
775         }
776         if ((access & Opcodes.ACC_DEPRECATED) != 0) {
777             out.putShort(newUTF8("Deprecated")).putInt(0);
778         }
779         if ((access & Opcodes.ACC_SYNTHETIC) != 0
780                 && (version & 0xffff) < Opcodes.V1_5)
781         {
782             out.putShort(newUTF8("Synthetic")).putInt(0);
783         }
784         if (version == Opcodes.V1_4) {
785             if ((access & Opcodes.ACC_ANNOTATION) != 0) {
786                 out.putShort(newUTF8("Annotation")).putInt(0);
787             }
788             if ((access & Opcodes.ACC_ENUM) != 0) {
789                 out.putShort(newUTF8("Enum")).putInt(0);
790             }
791         }
792         if (innerClasses != null) {
793             out.putShort(newUTF8("InnerClasses"));
794             out.putInt(innerClasses.length + 2).putShort(innerClassesCount);
795             out.putByteArray(innerClasses.data, 0, innerClasses.length);
796         }
797         if (anns != null) {
798             out.putShort(newUTF8("RuntimeVisibleAnnotations"));
799             anns.put(out);
800         }
801         if (ianns != null) {
802             out.putShort(newUTF8("RuntimeInvisibleAnnotations"));
803             ianns.put(out);
804         }
805         if (attrs != null) {
806             attrs.put(this, null, 0, -1, -1, out);
807         }
808         return out.data;
809     }
810
811     // ------------------------------------------------------------------------
812 // Utility methods: constant pool management
813 // ------------------------------------------------------------------------
814
815     /**
816      * Adds a number or string constant to the constant pool of the class being
817      * build. Does nothing if the constant pool already contains a similar item.
818      *
819      * @param cst the value of the constant to be added to the constant pool.
820      * This parameter must be an {@link Integer}, a {@link Float}, a
821      * {@link Long}, a {@link Double}, a {@link String} or a
822      * {@link Type}.
823      * @return a new or already existing constant item with the given value.
824      */
825     Item newConstItem(final Object cst) {
826         if (cst instanceof Integer ) {
827             int val = ((Integer ) cst).intValue();
828             return newInteger(val);
829         } else if (cst instanceof Byte ) {
830             int val = ((Byte ) cst).intValue();
831             return newInteger(val);
832         } else if (cst instanceof Character ) {
833             int val = ((Character ) cst).charValue();
834             return newInteger(val);
835         } else if (cst instanceof Short ) {
836             int val = ((Short ) cst).intValue();
837             return newInteger(val);
838         } else if (cst instanceof Boolean ) {
839             int val = ((Boolean ) cst).booleanValue() ? 1 : 0;
840             return newInteger(val);
841         } else if (cst instanceof Float ) {
842             float val = ((Float ) cst).floatValue();
843             return newFloat(val);
844         } else if (cst instanceof Long ) {
845             long val = ((Long ) cst).longValue();
846             return newLong(val);
847         } else if (cst instanceof Double ) {
848             double val = ((Double ) cst).doubleValue();
849             return newDouble(val);
850         } else if (cst instanceof String ) {
851             return newString((String ) cst);
852         } else if (cst instanceof Type) {
853             Type t = (Type) cst;
854             return newClassItem(t.getSort() == Type.OBJECT
855                     ? t.getInternalName()
856                     : t.getDescriptor());
857         } else {
858             throw new IllegalArgumentException ("value " + cst);
859         }
860     }
861
862     /**
863      * Adds a number or string constant to the constant pool of the class being
864      * build. Does nothing if the constant pool already contains a similar item.
865      * <i>This method is intended for {@link Attribute} sub classes, and is
866      * normally not needed by class generators or adapters.</i>
867      *
868      * @param cst the value of the constant to be added to the constant pool.
869      * This parameter must be an {@link Integer}, a {@link Float}, a
870      * {@link Long}, a {@link Double} or a {@link String}.
871      * @return the index of a new or already existing constant item with the
872      * given value.
873      */
874     public int newConst(final Object cst) {
875         return newConstItem(cst).index;
876     }
877
878     /**
879      * Adds an UTF8 string to the constant pool of the class being build. Does
880      * nothing if the constant pool already contains a similar item. <i>This
881      * method is intended for {@link Attribute} sub classes, and is normally not
882      * needed by class generators or adapters.</i>
883      *
884      * @param value the String value.
885      * @return the index of a new or already existing UTF8 item.
886      */
887     public int newUTF8(final String value) {
888         key.set(UTF8, value, null, null);
889         Item result = get(key);
890         if (result == null) {
891             pool.putByte(UTF8).putUTF8(value);
892             result = new Item(index++, key);
893             put(result);
894         }
895         return result.index;
896     }
897
898     /**
899      * Adds a class reference to the constant pool of the class being build.
900      * Does nothing if the constant pool already contains a similar item.
901      * <i>This method is intended for {@link Attribute} sub classes, and is
902      * normally not needed by class generators or adapters.</i>
903      *
904      * @param value the internal name of the class.
905      * @return the index of a new or already existing class reference item.
906      */
907     public int newClass(final String value) {
908         return newClassItem(value).index;
909     }
910
911     /**
912      * Adds a class reference to the constant pool of the class being build.
913      * Does nothing if the constant pool already contains a similar item.
914      * <i>This method is intended for {@link Attribute} sub classes, and is
915      * normally not needed by class generators or adapters.</i>
916      *
917      * @param value the internal name of the class.
918      * @return a new or already existing class reference item.
919      */
920     private Item newClassItem(final String value) {
921         key2.set(CLASS, value, null, null);
922         Item result = get(key2);
923         if (result == null) {
924             pool.put12(CLASS, newUTF8(value));
925             result = new Item(index++, key2);
926             put(result);
927         }
928         return result;
929     }
930
931     /**
932      * Adds a field reference to the constant pool of the class being build.
933      * Does nothing if the constant pool already contains a similar item.
934      * <i>This method is intended for {@link Attribute} sub classes, and is
935      * normally not needed by class generators or adapters.</i>
936      *
937      * @param owner the internal name of the field's owner class.
938      * @param name the field's name.
939      * @param desc the field's descriptor.
940      * @return the index of a new or already existing field reference item.
941      */
942     public int newField(final String owner, final String name, final String desc)
943     {
944         key3.set(FIELD, owner, name, desc);
945         Item result = get(key3);
946         if (result == null) {
947             put122(FIELD, newClass(owner), newNameType(name, desc));
948             result = new Item(index++, key3);
949             put(result);
950         }
951         return result.index;
952     }
953
954     /**
955      * Adds a method reference to the constant pool of the class being build.
956      * Does nothing if the constant pool already contains a similar item.
957      *
958      * @param owner the internal name of the method's owner class.
959      * @param name the method's name.
960      * @param desc the method's descriptor.
961      * @param itf <tt>true</tt> if <tt>owner</tt> is an interface.
962      * @return a new or already existing method reference item.
963      */
964     Item newMethodItem(
965         final String owner,
966         final String name,
967         final String desc,
968         final boolean itf)
969     {
970         int type = itf ? IMETH : METH;
971         key3.set(type, owner, name, desc);
972         Item result = get(key3);
973         if (result == null) {
974             put122(type, newClass(owner), newNameType(name, desc));
975             result = new Item(index++, key3);
976             put(result);
977         }
978         return result;
979     }
980
981     /**
982      * Adds a method reference to the constant pool of the class being build.
983      * Does nothing if the constant pool already contains a similar item.
984      * <i>This method is intended for {@link Attribute} sub classes, and is
985      * normally not needed by class generators or adapters.</i>
986      *
987      * @param owner the internal name of the method's owner class.
988      * @param name the method's name.
989      * @param desc the method's descriptor.
990      * @param itf <tt>true</tt> if <tt>owner</tt> is an interface.
991      * @return the index of a new or already existing method reference item.
992      */
993     public int newMethod(
994         final String owner,
995         final String name,
996         final String desc,
997         final boolean itf)
998     {
999         return newMethodItem(owner, name, desc, itf).index;
1000    }
1001
1002    /**
1003     * Adds an integer to the constant pool of the class being build. Does
1004     * nothing if the constant pool already contains a similar item.
1005     *
1006     * @param value the int value.
1007     * @return a new or already existing int item.
1008     */
1009    Item newInteger(final int value) {
1010        key.set(value);
1011        Item result = get(key);
1012        if (result == null) {
1013            pool.putByte(INT).putInt(value);
1014            result = new Item(index++, key);
1015            put(result);
1016        }
1017        return result;
1018    }
1019
1020    /**
1021     * Adds a float to the constant pool of the class being build. Does nothing
1022     * if the constant pool already contains a similar item.
1023     *
1024     * @param value the float value.
1025     * @return a new or already existing float item.
1026     */
1027    Item newFloat(final float value) {
1028        key.set(value);
1029        Item result = get(key);
1030        if (result == null) {
1031            pool.putByte(FLOAT).putInt(Float.floatToIntBits(value));
1032            result = new Item(index++, key);
1033            put(result);
1034        }
1035        return result;
1036    }
1037
1038    /**
1039     * Adds a long to the constant pool of the class being build. Does nothing
1040     * if the constant pool already contains a similar item.
1041     *
1042     * @param value the long value.
1043     * @return a new or already existing long item.
1044     */
1045    Item newLong(final long value) {
1046        key.set(value);
1047        Item result = get(key);
1048        if (result == null) {
1049            pool.putByte(LONG).putLong(value);
1050            result = new Item(index, key);
1051            put(result);
1052            index += 2;
1053        }
1054        return result;
1055    }
1056
1057    /**
1058     * Adds a double to the constant pool of the class being build. Does nothing
1059     * if the constant pool already contains a similar item.
1060     *
1061     * @param value the double value.
1062     * @return a new or already existing double item.
1063     */
1064    Item newDouble(final double value) {
1065        key.set(value);
1066        Item result = get(key);
1067        if (result == null) {
1068            pool.putByte(DOUBLE).putLong(Double.doubleToLongBits(value));
1069            result = new Item(index, key);
1070            put(result);
1071            index += 2;
1072        }
1073        return result;
1074    }
1075
1076    /**
1077     * Adds a string to the constant pool of the class being build. Does nothing
1078     * if the constant pool already contains a similar item.
1079     *
1080     * @param value the String value.
1081     * @return a new or already existing string item.
1082     */
1083    private Item newString(final String value) {
1084        key2.set(STR, value, null, null);
1085        Item result = get(key2);
1086        if (result == null) {
1087            pool.put12(STR, newUTF8(value));
1088            result = new Item(index++, key2);
1089            put(result);
1090        }
1091        return result;
1092    }
1093
1094    /**
1095     * Adds a name and type to the constant pool of the class being build. Does
1096     * nothing if the constant pool already contains a similar item. <i>This
1097     * method is intended for {@link Attribute} sub classes, and is normally not
1098     * needed by class generators or adapters.</i>
1099     *
1100     * @param name a name.
1101     * @param desc a type descriptor.
1102     * @return the index of a new or already existing name and type item.
1103     */
1104    public int newNameType(final String name, final String desc) {
1105        key2.set(NAME_TYPE, name, desc, null);
1106        Item result = get(key2);
1107        if (result == null) {
1108            put122(NAME_TYPE, newUTF8(name), newUTF8(desc));
1109            result = new Item(index++, key2);
1110            put(result);
1111        }
1112        return result.index;
1113    }
1114
1115    /**
1116     * Returns the constant pool's hash table item which is equal to the given
1117     * item.
1118     *
1119     * @param key a constant pool item.
1120     * @return the constant pool's hash table item which is equal to the given
1121     * item, or <tt>null</tt> if there is no such item.
1122     */
1123    private Item get(final Item key) {
1124        Item i = items[key.hashCode % items.length];
1125        while (i != null && !key.isEqualTo(i)) {
1126            i = i.next;
1127        }
1128        return i;
1129    }
1130
1131    /**
1132     * Puts the given item in the constant pool's hash table. The hash table
1133     * <i>must</i> not already contains this item.
1134     *
1135     * @param i the item to be added to the constant pool's hash table.
1136     */
1137    private void put(final Item i) {
1138        if (index > threshold) {
1139            int ll = items.length;
1140            int nl = ll * 2 + 1;
1141            Item[] newItems = new Item[nl];
1142            for (int l = ll - 1; l >= 0; --l) {
1143                Item j = items[l];
1144                while (j != null) {
1145                    int index = j.hashCode % newItems.length;
1146                    Item k = j.next;
1147                    j.next = newItems[index];
1148                    newItems[index] = j;
1149                    j = k;
1150                }
1151            }
1152            items = newItems;
1153            threshold = (int) (nl * 0.75);
1154        }
1155        int index = i.hashCode % items.length;
1156        i.next = items[index];
1157        items[index] = i;
1158    }
1159
1160    /**
1161     * Puts one byte and two shorts into the constant pool.
1162     *
1163     * @param b a byte.
1164     * @param s1 a short.
1165     * @param s2 another short.
1166     */
1167    private void put122(final int b, final int s1, final int s2) {
1168        pool.put12(b, s1).putShort(s2);
1169    }
1170}
1171

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