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      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 org.objectweb.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 final byte[] TYPE;
    132 
    133     /**
    134      * The type of CONSTANT_Class constant pool items.
    135      */
    136     static final int CLASS = 7;
    137 
    138     /**
    139      * The type of CONSTANT_Fieldref constant pool items.
    140      */
    141     static final int FIELD = 9;
    142 
    143     /**
    144      * The type of CONSTANT_Methodref constant pool items.
    145      */
    146     static final int METH = 10;
    147 
    148     /**
    149      * The type of CONSTANT_InterfaceMethodref constant pool items.
    150      */
    151     static final int IMETH = 11;
    152 
    153     /**
    154      * The type of CONSTANT_String constant pool items.
    155      */
    156     static final int STR = 8;
    157 
    158     /**
    159      * The type of CONSTANT_Integer constant pool items.
    160      */
    161     static final int INT = 3;
    162 
    163     /**
    164      * The type of CONSTANT_Float constant pool items.
    165      */
    166     static final int FLOAT = 4;
    167 
    168     /**
    169      * The type of CONSTANT_Long constant pool items.
    170      */
    171     static final int LONG = 5;
    172 
    173     /**
    174      * The type of CONSTANT_Double constant pool items.
    175      */
    176     static final int DOUBLE = 6;
    177 
    178     /**
    179      * The type of CONSTANT_NameAndType constant pool items.
    180      */
    181     static final int NAME_TYPE = 12;
    182 
    183     /**
    184      * The type of CONSTANT_Utf8 constant pool items.
    185      */
    186     static final int UTF8 = 1;
    187 
    188     /**
    189      * The type of CONSTANT_MethodType constant pool items.
    190      */
    191     static final int MTYPE = 16;
    192 
    193     /**
    194      * The type of CONSTANT_MethodHandle constant pool items.
    195      */
    196     static final int HANDLE = 15;
    197 
    198     /**
    199      * The type of CONSTANT_InvokeDynamic constant pool items.
    200      */
    201     static final int INDY = 18;
    202 
    203     /**
    204      * The base value for all CONSTANT_MethodHandle constant pool items.
    205      * Internally, ASM store the 9 variations of CONSTANT_MethodHandle into 9
    206      * different items.
    207      */
    208     static final int HANDLE_BASE = 20;
    209 
    210     /**
    211      * Normal type Item stored in the ClassWriter {@link ClassWriter#typeTable},
    212      * instead of the constant pool, in order to avoid clashes with normal
    213      * constant pool items in the ClassWriter constant pool's hash table.
    214      */
    215     static final int TYPE_NORMAL = 30;
    216 
    217     /**
    218      * Uninitialized type Item stored in the ClassWriter
    219      * {@link ClassWriter#typeTable}, instead of the constant pool, in order to
    220      * avoid clashes with normal constant pool items in the ClassWriter constant
    221      * pool's hash table.
    222      */
    223     static final int TYPE_UNINIT = 31;
    224 
    225     /**
    226      * Merged type Item stored in the ClassWriter {@link ClassWriter#typeTable},
    227      * instead of the constant pool, in order to avoid clashes with normal
    228      * constant pool items in the ClassWriter constant pool's hash table.
    229      */
    230     static final int TYPE_MERGED = 32;
    231 
    232     /**
    233      * The type of BootstrapMethods items. These items are stored in a special
    234      * class attribute named BootstrapMethods and not in the constant pool.
    235      */
    236     static final int BSM = 33;
    237 
    238     /**
    239      * The class reader from which this class writer was constructed, if any.
    240      */
    241     ClassReader cr;
    242 
    243     /**
    244      * Minor and major version numbers of the class to be generated.
    245      */
    246     int version;
    247 
    248     /**
    249      * Index of the next item to be added in the constant pool.
    250      */
    251     int index;
    252 
    253     /**
    254      * The constant pool of this class.
    255      */
    256     ByteVector pool;
    257 
    258     /**
    259      * The constant pool's hash table data.
    260      */
    261     Item[] items;
    262 
    263     /**
    264      * The threshold of the constant pool's hash table.
    265      */
    266     int threshold;
    267 
    268     /**
    269      * A reusable key used to look for items in the hash {@link #items items}.
    270      */
    271     Item key;
    272 
    273     /**
    274      * A reusable key used to look for items in the hash {@link #items items}.
    275      */
    276     Item key2;
    277 
    278     /**
    279      * A reusable key used to look for items in the hash {@link #items items}.
    280      */
    281     Item key3;
    282 
    283     /**
    284      * A reusable key used to look for items in the hash {@link #items items}.
    285      */
    286     Item key4;
    287 
    288     /**
    289      * The access flags of this class.
    290      */
    291     private int access;
    292 
    293     /**
    294      * The constant pool item that contains the internal name of this class.
    295      */
    296     private int name;
    297 
    298     /**
    299      * The constant pool item that contains the signature of this class.
    300      */
    301     private int signature;
    302 
    303     /**
    304      * The constant pool item that contains the internal name of the super class
    305      * of this class.
    306      */
    307     private int superName;
    308 
    309     /**
    310      * Number of interfaces implemented or extended by this class or interface.
    311      */
    312     private int interfaceCount;
    313 
    314     /**
    315      * The interfaces implemented or extended by this class or interface. More
    316      * precisely, this array contains the indexes of the constant pool items
    317      * that contain the internal names of these interfaces.
    318      */
    319     private int[] interfaces;
    320 
    321     /**
    322      * The index of the constant pool item that contains the name of the source
    323      * file from which this class was compiled.
    324      */
    325     private int sourceFile;
    326 
    327     /**
    328      * The SourceDebug attribute of this class.
    329      */
    330     private ByteVector sourceDebug;
    331 
    332     /**
    333      * The constant pool item that contains the name of the enclosing class of
    334      * this class.
    335      */
    336     private int enclosingMethodOwner;
    337 
    338     /**
    339      * The constant pool item that contains the name and descriptor of the
    340      * enclosing method of this class.
    341      */
    342     private int enclosingMethod;
    343 
    344     /**
    345      * The runtime visible annotations of this class.
    346      */
    347     private AnnotationWriter anns;
    348 
    349     /**
    350      * The runtime invisible annotations of this class.
    351      */
    352     private AnnotationWriter ianns;
    353 
    354     //jaime
    355     private TypeAnnotationWriter xanns;
    356     private TypeAnnotationWriter ixanns;
    357     //end jaime
    358 
    359     /**
    360      * The non standard attributes of this class.
    361      */
    362     private Attribute attrs;
    363 
    364     /**
    365      * The number of entries in the InnerClasses attribute.
    366      */
    367     private int innerClassesCount;
    368 
    369     /**
    370      * The InnerClasses attribute.
    371      */
    372     private ByteVector innerClasses;
    373 
    374     /**
    375      * The number of entries in the BootstrapMethods attribute.
    376      */
    377     int bootstrapMethodsCount;
    378 
    379     /**
    380      * The BootstrapMethods attribute.
    381      */
    382     ByteVector bootstrapMethods;
    383 
    384     /**
    385      * The fields of this class. These fields are stored in a linked list of
    386      * {@link FieldWriter} objects, linked to each other by their
    387      * {@link FieldWriter#next} field. This field stores the first element of
    388      * this list.
    389      */
    390     FieldWriter firstField;
    391 
    392     /**
    393      * The fields of this class. These fields are stored in a linked list of
    394      * {@link FieldWriter} objects, linked to each other by their
    395      * {@link FieldWriter#next} field. This field stores the last element of
    396      * this list.
    397      */
    398     FieldWriter lastField;
    399 
    400     /**
    401      * The methods of this class. These methods are stored in a linked list of
    402      * {@link MethodWriter} objects, linked to each other by their
    403      * {@link MethodWriter#next} field. This field stores the first element of
    404      * this list.
    405      */
    406     MethodWriter firstMethod;
    407 
    408     /**
    409      * The methods of this class. These methods are stored in a linked list of
    410      * {@link MethodWriter} objects, linked to each other by their
    411      * {@link MethodWriter#next} field. This field stores the last element of
    412      * this list.
    413      */
    414     MethodWriter lastMethod;
    415 
    416     /**
    417      * <tt>true</tt> if the maximum stack size and number of local variables
    418      * must be automatically computed.
    419      */
    420     private final boolean computeMaxs;
    421 
    422     // ------------------------------------------------------------------------
    423     // Static initializer
    424     // ------------------------------------------------------------------------
    425 
    426     /**
    427      * Computes the instruction types of JVM opcodes.
    428      */
    429     static {
    430         int i;
    431         byte[] b = new byte[220];
    432         String s = "AAAAAAAAAAAAAAAABCKLLDDDDDEEEEEEEEEEEEEEEEEEEEAAAAAAAADD"
    433                 + "DDDEEEEEEEEEEEEEEEEEEEEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
    434                 + "AAAAAAAAAAAAAAAAAMAAAAAAAAAAAAAAAAAAAAIIIIIIIIIIIIIIIIDNOAA"
    435                 + "AAAAGGGGGGGHSFBFAAFFAAQPIIJJIIIIIIIIIIIIIIIIII";
    436         for (i = 0; i < b.length; ++i) {
    437             b[i] = (byte) (s.charAt(i) - 'A');
    438         }
    439         TYPE = b;
    440 
    441         // code to generate the above string
    442         //
    443         // // SBYTE_INSN instructions
    444         // b[Constants.NEWARRAY] = SBYTE_INSN;
    445         // b[Constants.BIPUSH] = SBYTE_INSN;
    446         //
    447         // // SHORT_INSN instructions
    448         // b[Constants.SIPUSH] = SHORT_INSN;
    449         //
    450         // // (IMPL)VAR_INSN instructions
    451         // b[Constants.RET] = VAR_INSN;
    452         // for (i = Constants.ILOAD; i <= Constants.ALOAD; ++i) {
    453         // b[i] = VAR_INSN;
    454         // }
    455         // for (i = Constants.ISTORE; i <= Constants.ASTORE; ++i) {
    456         // b[i] = VAR_INSN;
    457         // }
    458         // for (i = 26; i <= 45; ++i) { // ILOAD_0 to ALOAD_3
    459         // b[i] = IMPLVAR_INSN;
    460         // }
    461         // for (i = 59; i <= 78; ++i) { // ISTORE_0 to ASTORE_3
    462         // b[i] = IMPLVAR_INSN;
    463         // }
    464         //
    465         // // TYPE_INSN instructions
    466         // b[Constants.NEW] = TYPE_INSN;
    467         // b[Constants.ANEWARRAY] = TYPE_INSN;
    468         // b[Constants.CHECKCAST] = TYPE_INSN;
    469         // b[Constants.INSTANCEOF] = TYPE_INSN;
    470         //
    471         // // (Set)FIELDORMETH_INSN instructions
    472         // for (i = Constants.GETSTATIC; i <= Constants.INVOKESTATIC; ++i) {
    473         // b[i] = FIELDORMETH_INSN;
    474         // }
    475         // b[Constants.INVOKEINTERFACE] = ITFMETH_INSN;
    476         //
    477         // b[Constants.INVOKEDYNAMIC] = INDY;
    478         //
    479         // // LABEL(W)_INSN instructions
    480         // for (i = Constants.IFEQ; i <= Constants.JSR; ++i) {
    481         // b[i] = LABEL_INSN;
    482         // }
    483         // b[Constants.IFNULL] = LABEL_INSN;
    484         // b[Constants.IFNONNULL] = LABEL_INSN;
    485         // b[200] = LABELW_INSN; // GOTO_W
    486         // b[201] = LABELW_INSN; // JSR_W
    487         // // temporary opcodes used internally by ASM - see Label and
    488         // MethodWriter
    489         // for (i = 202; i < 220; ++i) {
    490         // b[i] = LABEL_INSN;
    491         // }
    492         //
    493         // // LDC(_W) instructions
    494         // b[Constants.LDC] = LDC_INSN;
    495         // b[19] = LDCW_INSN; // LDC_W
    496         // b[20] = LDCW_INSN; // LDC2_W
    497         //
    498         // // special instructions
    499         // b[Constants.IINC] = IINC_INSN;
    500         // b[Constants.TABLESWITCH] = TABL_INSN;
    501         // b[Constants.LOOKUPSWITCH] = LOOK_INSN;
    502         // b[Constants.MULTIANEWARRAY] = MANA_INSN;
    503         // b[196] = WIDE_INSN; // WIDE
    504         //
    505         // for (i = 0; i < b.length; ++i) {
    506         // System.err.print((char)('A' + b[i]));
    507         // }
    508         // System.err.println();
    509     }
    510 
    511     // ------------------------------------------------------------------------
    512     // Constructor
    513     // ------------------------------------------------------------------------
    514 
    515     /**
    516      * Constructs a new {@link ClassWriter ClassWriter} object.
    517      *
    518      * @param computeMaxs <tt>true</tt> if the maximum stack size and the
    519      *        maximum number of local variables must be automatically computed.
    520      *        If this flag is <tt>true</tt>, then the arguments of the
    521      *        {@link MethodVisitor#visitMaxs visitMaxs} method of the
    522      *        {@link MethodVisitor} returned by the
    523      *        {@link #visitMethod visitMethod} method will be ignored, and
    524      *        computed automatically from the signature and the bytecode of each
    525      *        method.
    526      */
    527     public ClassWriter(final boolean computeMaxs) {
    528         this(computeMaxs, false);
    529     }
    530 
    531     /**
    532      * Constructs a new {@link ClassWriter} object.
    533      *
    534      * @param computeMaxs <tt>true</tt> if the maximum stack size and the
    535      *        maximum number of local variables must be automatically computed.
    536      *        If this flag is <tt>true</tt>, then the arguments of the
    537      *        {@link MethodVisitor#visitMaxs visitMaxs} method of the
    538      *        {@link MethodVisitor} returned by the
    539      *        {@link #visitMethod visitMethod} method will be ignored, and
    540      *        computed automatically from the signature and the bytecode of each
    541      *        method.
    542      * @param skipUnknownAttributes <b>Deprecated</b>. The value of this
    543      *        parameter is ignored.
    544      */
    545     public ClassWriter(
    546         final boolean computeMaxs,
    547         final boolean skipUnknownAttributes)
    548     {
    549         index = 1;
    550         pool = new ByteVector();
    551         items = new Item[256];
    552         threshold = (int) (0.75d * items.length);
    553         key = new Item();
    554         key2 = new Item();
    555         key3 = new Item();
    556         key4 = new Item();
    557         this.computeMaxs = computeMaxs;
    558     }
    559 
    560     /**
    561      * Constructs a new {@link ClassWriter} object and enables optimizations for
    562      * "mostly add" bytecode transformations. These optimizations are the
    563      * following:
    564      *
    565      * <ul> <li>The constant pool from the original class is copied as is in
    566      * the new class, which saves time. New constant pool entries will be added
    567      * at the end if necessary, but unused constant pool entries <i>won't be
    568      * removed</i>.</li> <li>Methods that are not transformed are copied as
    569      * is in the new class, directly from the original class bytecode (i.e.
    570      * without emitting visit events for all the method instructions), which
    571      * saves a <i>lot</i> of time. Untransformed methods are detected by the
    572      * fact that the {@link ClassReader} receives {@link MethodVisitor} objects
    573      * that come from a {@link ClassWriter} (and not from a custom
    574      * {@link ClassAdapter} or any other {@link ClassVisitor} instance).</li>
    575      * </ul>
    576      *
    577      * @param classReader the {@link ClassReader} used to read the original
    578      *        class. It will be used to copy the entire constant pool from the
    579      *        original class and also to copy other fragments of original
    580      *        bytecode where applicable.
    581      * @param computeMaxs <tt>true</tt> if the maximum stack size and the
    582      *        maximum number of local variables must be automatically computed.
    583      *        If this flag is <tt>true</tt>, then the arguments of the
    584      *        {@link MethodVisitor#visitMaxs visitMaxs} method of the
    585      *        {@link MethodVisitor} returned by the
    586      *        {@link #visitMethod visitMethod} method will be ignored, and
    587      *        computed automatically from the signature and the bytecode of each
    588      *        method.
    589      */
    590     public ClassWriter(
    591         final ClassReader classReader,
    592         final boolean computeMaxs)
    593     {
    594         this(computeMaxs, false);
    595         classReader.copyPool(this);
    596         this.cr = classReader;
    597     }
    598 
    599     // ------------------------------------------------------------------------
    600     // Implementation of the ClassVisitor interface
    601     // ------------------------------------------------------------------------
    602 
    603     @Override
    604     public void visit(
    605         final int version,
    606         final int access,
    607         final String name,
    608         final String signature,
    609         final String superName,
    610         final String[] interfaces)
    611     {
    612         this.version = version;
    613         this.access = access;
    614         this.name = newClass(name);
    615         if (signature != null) {
    616             this.signature = newUTF8(signature);
    617         }
    618         this.superName = superName == null ? 0 : newClass(superName);
    619         if (interfaces != null && interfaces.length > 0) {
    620             interfaceCount = interfaces.length;
    621             this.interfaces = new int[interfaceCount];
    622             for (int i = 0; i < interfaceCount; ++i) {
    623                 this.interfaces[i] = newClass(interfaces[i]);
    624             }
    625         }
    626     }
    627 
    628     @Override
    629     public void visitSource(final String file, final String debug) {
    630         if (file != null) {
    631             sourceFile = newUTF8(file);
    632         }
    633         if (debug != null) {
    634             sourceDebug = new ByteVector().putUTF8(debug);
    635         }
    636     }
    637 
    638     @Override
    639     public void visitOuterClass(
    640         final String owner,
    641         final String name,
    642         final String desc)
    643     {
    644         enclosingMethodOwner = newClass(owner);
    645         if (name != null && desc != null) {
    646             enclosingMethod = newNameType(name, desc);
    647         }
    648     }
    649 
    650     @Override
    651     public AnnotationVisitor visitAnnotation(String desc, boolean visible) {
    652         ByteVector bv = new ByteVector();
    653         // write type, and reserve space for values count
    654         bv.putShort(newUTF8(desc)).putShort(0);
    655         AnnotationWriter aw = new AnnotationWriter(this, true, bv, bv, 2);
    656         if (visible) {
    657             aw.next = anns;
    658             anns = aw;
    659         } else {
    660             aw.next = ianns;
    661             ianns = aw;
    662         }
    663         return aw;
    664     }
    665 
    666     //jaime
    667     @Override
    668     public TypeAnnotationVisitor visitTypeAnnotation(String desc,
    669         boolean visible,
    670         boolean inCode)
    671     {
    672         ByteVector bv = new ByteVector();
    673         TypeAnnotationWriter xaw = new TypeAnnotationWriter(this, true, bv, bv, desc);
    674         if(visible) {
    675             xaw.next = xanns;
    676             xanns = xaw;
    677         } else {
    678             xaw.next = ixanns;
    679             ixanns = xaw;
    680         }
    681 
    682         return xaw;
    683     }
    684     //end jaime
    685 
    686     @Override
    687     public void visitAttribute(final Attribute attr) {
    688         attr.next = attrs;
    689         attrs = attr;
    690     }
    691 
    692     @Override
    693     public void visitInnerClass(
    694         final String name,
    695         final String outerName,
    696         final String innerName,
    697         final int access)
    698     {
    699         if (innerClasses == null) {
    700             innerClasses = new ByteVector();
    701         }
    702         ++innerClassesCount;
    703         innerClasses.putShort(name == null ? 0 : newClass(name));
    704         innerClasses.putShort(outerName == null ? 0 : newClass(outerName));
    705         innerClasses.putShort(innerName == null ? 0 : newUTF8(innerName));
    706         innerClasses.putShort(access);
    707     }
    708 
    709     @Override
    710     public FieldVisitor visitField(
    711         final int access,
    712         final String name,
    713         final String desc,
    714         final String signature,
    715         final Object value)
    716     {
    717         return new FieldWriter(this, access, name, desc, signature, value);
    718     }
    719 
    720     @Override
    721     public MethodVisitor visitMethod(
    722         final int access,
    723         final String name,
    724         final String desc,
    725         final String signature,
    726         final String[] exceptions)
    727     {
    728         return new MethodWriter(this,
    729                 access,
    730                 name,
    731                 desc,
    732                 signature,
    733                 exceptions,
    734                 computeMaxs);
    735     }
    736 
    737     @Override
    738     public void visitEnd() {
    739     }
    740 
    741     // ------------------------------------------------------------------------
    742     // Other public methods
    743     // ------------------------------------------------------------------------
    744 
    745     /**
    746      * Returns the bytecode of the class that was build with this class writer.
    747      *
    748      * @return the bytecode of the class that was build with this class writer.
    749      */
    750     public byte[] toByteArray() {
    751         // computes the real size of the bytecode of this class
    752         int size = 24 + 2 * interfaceCount;
    753         int nbFields = 0;
    754         FieldWriter fb = firstField;
    755         while (fb != null) {
    756             ++nbFields;
    757             size += fb.getSize();
    758             fb = fb.next;
    759         }
    760         int nbMethods = 0;
    761         MethodWriter mb = firstMethod;
    762         while (mb != null) {
    763             ++nbMethods;
    764             size += mb.getSize();
    765             mb = mb.next;
    766         }
    767         int attributeCount = 0;
    768         if (bootstrapMethods != null) {
    769             // we put it as first attribute in order to improve a bit
    770             // ClassReader.copyBootstrapMethods
    771             ++attributeCount;
    772             size += 8 + bootstrapMethods.length;
    773             newUTF8("BootstrapMethods");
    774         }
    775         if (signature != 0) {
    776             ++attributeCount;
    777             size += 8;
    778             newUTF8("Signature");
    779         }
    780         if (sourceFile != 0) {
    781             ++attributeCount;
    782             size += 8;
    783             newUTF8("SourceFile");
    784         }
    785         if (sourceDebug != null) {
    786             ++attributeCount;
    787             size += sourceDebug.length + 4;
    788             newUTF8("SourceDebugExtension");
    789         }
    790         if (enclosingMethodOwner != 0) {
    791             ++attributeCount;
    792             size += 10;
    793             newUTF8("EnclosingMethod");
    794         }
    795         if ((access & Opcodes.ACC_DEPRECATED) != 0) {
    796             ++attributeCount;
    797             size += 6;
    798             newUTF8("Deprecated");
    799         }
    800         if ((access & Opcodes.ACC_SYNTHETIC) != 0
    801                 && (version & 0xffff) < Opcodes.V1_5)
    802         {
    803             ++attributeCount;
    804             size += 6;
    805             newUTF8("Synthetic");
    806         }
    807         if (version == Opcodes.V1_4) {
    808             if ((access & Opcodes.ACC_ANNOTATION) != 0) {
    809                 ++attributeCount;
    810                 size += 6;
    811                 newUTF8("Annotation");
    812             }
    813             if ((access & Opcodes.ACC_ENUM) != 0) {
    814                 ++attributeCount;
    815                 size += 6;
    816                 newUTF8("Enum");
    817             }
    818         }
    819         if (innerClasses != null) {
    820             ++attributeCount;
    821             size += 8 + innerClasses.length;
    822             newUTF8("InnerClasses");
    823         }
    824         if (anns != null) {
    825             ++attributeCount;
    826             size += 8 + anns.getSize();
    827             newUTF8("RuntimeVisibleAnnotations");
    828         }
    829         if (ianns != null) {
    830             ++attributeCount;
    831             size += 8 + ianns.getSize();
    832             newUTF8("RuntimeInvisibleAnnotations");
    833         }
    834 
    835         if(xanns != null) {
    836           ++attributeCount;
    837           size += 8 + xanns.getSize();
    838           newUTF8("RuntimeVisibleTypeAnnotations");
    839         }
    840         if(ixanns != null) {
    841           ++attributeCount;
    842           size += 8 + ixanns.getSize();
    843           newUTF8("RuntimeInvisibleTypeAnnotations");
    844         }
    845 
    846         if (attrs != null) {
    847             attributeCount += attrs.getCount();
    848             size += attrs.getSize(this, null, 0, -1, -1);
    849         }
    850         size += pool.length;
    851         // allocates a byte vector of this size, in order to avoid unnecessary
    852         // arraycopy operations in the ByteVector.enlarge() method
    853         ByteVector out = new ByteVector(size);
    854         out.putInt(0xCAFEBABE).putInt(version);
    855         out.putShort(index).putByteArray(pool.data, 0, pool.length);
    856         out.putShort(access).putShort(name).putShort(superName);
    857         out.putShort(interfaceCount);
    858         for (int i = 0; i < interfaceCount; ++i) {
    859             out.putShort(interfaces[i]);
    860         }
    861         out.putShort(nbFields);
    862         fb = firstField;
    863         while (fb != null) {
    864             fb.put(out);
    865             fb = fb.next;
    866         }
    867         out.putShort(nbMethods);
    868         mb = firstMethod;
    869         while (mb != null) {
    870             mb.put(out);
    871             mb = mb.next;
    872         }
    873         out.putShort(attributeCount);
    874         if (bootstrapMethods != null) {
    875             out.putShort(newUTF8("BootstrapMethods"));
    876             out.putInt(bootstrapMethods.length + 2).putShort(
    877                     bootstrapMethodsCount);
    878             out.putByteArray(bootstrapMethods.data, 0, bootstrapMethods.length);
    879         }
    880         if (signature != 0) {
    881             out.putShort(newUTF8("Signature")).putInt(2).putShort(signature);
    882         }
    883         if (sourceFile != 0) {
    884             out.putShort(newUTF8("SourceFile")).putInt(2).putShort(sourceFile);
    885         }
    886         if (sourceDebug != null) {
    887             int len = sourceDebug.length - 2;
    888             out.putShort(newUTF8("SourceDebugExtension")).putInt(len);
    889             out.putByteArray(sourceDebug.data, 2, len);
    890         }
    891         if (enclosingMethodOwner != 0) {
    892             out.putShort(newUTF8("EnclosingMethod")).putInt(4);
    893             out.putShort(enclosingMethodOwner).putShort(enclosingMethod);
    894         }
    895         if ((access & Opcodes.ACC_DEPRECATED) != 0) {
    896             out.putShort(newUTF8("Deprecated")).putInt(0);
    897         }
    898         if ((access & Opcodes.ACC_SYNTHETIC) != 0
    899                 && (version & 0xffff) < Opcodes.V1_5)
    900         {
    901             out.putShort(newUTF8("Synthetic")).putInt(0);
    902         }
    903         if (version == Opcodes.V1_4) {
    904             if ((access & Opcodes.ACC_ANNOTATION) != 0) {
    905                 out.putShort(newUTF8("Annotation")).putInt(0);
    906             }
    907             if ((access & Opcodes.ACC_ENUM) != 0) {
    908                 out.putShort(newUTF8("Enum")).putInt(0);
    909             }
    910         }
    911         if (innerClasses != null) {
    912             out.putShort(newUTF8("InnerClasses"));
    913             out.putInt(innerClasses.length + 2).putShort(innerClassesCount);
    914             out.putByteArray(innerClasses.data, 0, innerClasses.length);
    915         }
    916         if (anns != null) {
    917             out.putShort(newUTF8("RuntimeVisibleAnnotations"));
    918             anns.put(out);
    919         }
    920         if (ianns != null) {
    921             out.putShort(newUTF8("RuntimeInvisibleAnnotations"));
    922             ianns.put(out);
    923         }
    924         if(xanns != null) {
    925           out.putShort(newUTF8("RuntimeVisibleTypeAnnotations"));
    926           xanns.put(out);
    927         }
    928         if(ixanns != null) {
    929           out.putShort(newUTF8("RuntimeInvisibleTypeAnnotations"));
    930           ixanns.put(out);
    931         }
    932         if (attrs != null) {
    933             attrs.put(this, null, 0, -1, -1, out);
    934         }
    935         return out.data;
    936     }
    937 
    938     // ------------------------------------------------------------------------
    939     // Utility methods: constant pool management
    940     // ------------------------------------------------------------------------
    941 
    942     /**
    943      * Adds a number or string constant to the constant pool of the class being
    944      * build. Does nothing if the constant pool already contains a similar item.
    945      *
    946      * @param cst
    947      *            the value of the constant to be added to the constant pool.
    948      *            This parameter must be an {@link Integer}, a {@link Float}, a
    949      *            {@link Long}, a {@link Double}, a {@link String} or a
    950      *            {@link Type}.
    951      * @return a new or already existing constant item with the given value.
    952      */
    953     Item newConstItem(final Object cst) {
    954         if (cst instanceof Integer) {
    955             int val = ((Integer) cst).intValue();
    956             return newInteger(val);
    957         } else if (cst instanceof Byte) {
    958             int val = ((Byte) cst).intValue();
    959             return newInteger(val);
    960         } else if (cst instanceof Character) {
    961             int val = ((Character) cst).charValue();
    962             return newInteger(val);
    963         } else if (cst instanceof Short) {
    964             int val = ((Short) cst).intValue();
    965             return newInteger(val);
    966         } else if (cst instanceof Boolean) {
    967             int val = ((Boolean) cst).booleanValue() ? 1 : 0;
    968             return newInteger(val);
    969         } else if (cst instanceof Float) {
    970             float val = ((Float) cst).floatValue();
    971             return newFloat(val);
    972         } else if (cst instanceof Long) {
    973             long val = ((Long) cst).longValue();
    974             return newLong(val);
    975         } else if (cst instanceof Double) {
    976             double val = ((Double) cst).doubleValue();
    977             return newDouble(val);
    978         } else if (cst instanceof String) {
    979             return newString((String) cst);
    980         } else if (cst instanceof Type) {
    981             Type t = (Type) cst;
    982             int s = t.getSort();
    983             if (s == Type.OBJECT) {
    984                 return newClassItem(t.getInternalName());
    985             } else if (s == Type.METHOD) {
    986                 return newMethodTypeItem(t.getDescriptor());
    987             } else { // s == primitive type or array
    988                 return newClassItem(t.getDescriptor());
    989             }
    990         } else if (cst instanceof Handle) {
    991             Handle h = (Handle) cst;
    992             return newHandleItem(h.tag, h.owner, h.name, h.desc);
    993         } else {
    994             throw new IllegalArgumentException("value " + cst);
    995         }
    996     }
    997 
    998     /**
    999      * Adds a number or string constant to the constant pool of the class being
   1000      * build. Does nothing if the constant pool already contains a similar item.
   1001      * <i>This method is intended for {@link Attribute} sub classes, and is
   1002      * normally not needed by class generators or adapters.</i>
   1003      *
   1004      * @param cst the value of the constant to be added to the constant pool.
   1005      *        This parameter must be an {@link Integer}, a {@link Float}, a
   1006      *        {@link Long}, a {@link Double} or a {@link String}.
   1007      * @return the index of a new or already existing constant item with the
   1008      *         given value.
   1009      */
   1010     public int newConst(final Object cst) {
   1011         return newConstItem(cst).index;
   1012     }
   1013 
   1014     /**
   1015      * Adds an UTF8 string to the constant pool of the class being build. Does
   1016      * nothing if the constant pool already contains a similar item. <i>This
   1017      * method is intended for {@link Attribute} sub classes, and is normally not
   1018      * needed by class generators or adapters.</i>
   1019      *
   1020      * @param value the String value.
   1021      * @return the index of a new or already existing UTF8 item.
   1022      */
   1023     public int newUTF8(final String value) {
   1024         key.set(UTF8, value, null, null);
   1025         Item result = get(key);
   1026         if (result == null) {
   1027             pool.putByte(UTF8).putUTF8(value);
   1028             result = new Item(index++, key);
   1029             put(result);
   1030         }
   1031         return result.index;
   1032     }
   1033 
   1034     /**
   1035      * Adds a class reference to the constant pool of the class being build.
   1036      * Does nothing if the constant pool already contains a similar item.
   1037      * <i>This method is intended for {@link Attribute} sub classes, and is
   1038      * normally not needed by class generators or adapters.</i>
   1039      *
   1040      * @param value the internal name of the class.
   1041      * @return the index of a new or already existing class reference item.
   1042      */
   1043     public int newClass(final String value) {
   1044         return newClassItem(value).index;
   1045     }
   1046 
   1047     /**
   1048      * Adds a class reference to the constant pool of the class being build.
   1049      * Does nothing if the constant pool already contains a similar item.
   1050      * <i>This method is intended for {@link Attribute} sub classes, and is
   1051      * normally not needed by class generators or adapters.</i>
   1052      *
   1053      * @param value the internal name of the class.
   1054      * @return a new or already existing class reference item.
   1055      */
   1056     private Item newClassItem(final String value) {
   1057         key2.set(CLASS, value, null, null);
   1058         Item result = get(key2);
   1059         if (result == null) {
   1060             pool.put12(CLASS, newUTF8(value));
   1061             result = new Item(index++, key2);
   1062             put(result);
   1063         }
   1064         return result;
   1065     }
   1066 
   1067     /**
   1068      * Adds a method type reference to the constant pool of the class being
   1069      * build. Does nothing if the constant pool already contains a similar item.
   1070      * <i>This method is intended for {@link Attribute} sub classes, and is
   1071      * normally not needed by class generators or adapters.</i>
   1072      *
   1073      * @param methodDesc
   1074      *            method descriptor of the method type.
   1075      * @return a new or already existing method type reference item.
   1076      */
   1077     Item newMethodTypeItem(final String methodDesc) {
   1078         key2.set(MTYPE, methodDesc, null, null);
   1079         Item result = get(key2);
   1080         if (result == null) {
   1081             pool.put12(MTYPE, newUTF8(methodDesc));
   1082             result = new Item(index++, key2);
   1083             put(result);
   1084         }
   1085         return result;
   1086     }
   1087 
   1088     /**
   1089      * Adds a method type reference to the constant pool of the class being
   1090      * build. Does nothing if the constant pool already contains a similar item.
   1091      * <i>This method is intended for {@link Attribute} sub classes, and is
   1092      * normally not needed by class generators or adapters.</i>
   1093      *
   1094      * @param methodDesc
   1095      *            method descriptor of the method type.
   1096      * @return the index of a new or already existing method type reference
   1097      *         item.
   1098      */
   1099     public int newMethodType(final String methodDesc) {
   1100         return newMethodTypeItem(methodDesc).index;
   1101     }
   1102 
   1103     /**
   1104      * Adds a handle to the constant pool of the class being build. Does nothing
   1105      * if the constant pool already contains a similar item. <i>This method is
   1106      * intended for {@link Attribute} sub classes, and is normally not needed by
   1107      * class generators or adapters.</i>
   1108      *
   1109      * @param tag
   1110      *            the kind of this handle. Must be {@link Opcodes#H_GETFIELD},
   1111      *            {@link Opcodes#H_GETSTATIC}, {@link Opcodes#H_PUTFIELD},
   1112      *            {@link Opcodes#H_PUTSTATIC}, {@link Opcodes#H_INVOKEVIRTUAL},
   1113      *            {@link Opcodes#H_INVOKESTATIC},
   1114      *            {@link Opcodes#H_INVOKESPECIAL},
   1115      *            {@link Opcodes#H_NEWINVOKESPECIAL} or
   1116      *            {@link Opcodes#H_INVOKEINTERFACE}.
   1117      * @param owner
   1118      *            the internal name of the field or method owner class.
   1119      * @param name
   1120      *            the name of the field or method.
   1121      * @param desc
   1122      *            the descriptor of the field or method.
   1123      * @return a new or an already existing method type reference item.
   1124      */
   1125     Item newHandleItem(final int tag, final String owner, final String name,
   1126             final String desc) {
   1127         key4.set(HANDLE_BASE + tag, owner, name, desc);
   1128         Item result = get(key4);
   1129         if (result == null) {
   1130             if (tag <= Opcodes.H_PUTSTATIC) {
   1131                 put112(HANDLE, tag, newField(owner, name, desc));
   1132             } else {
   1133                 put112(HANDLE,
   1134                         tag,
   1135                         newMethod(owner, name, desc,
   1136                                 tag == Opcodes.H_INVOKEINTERFACE));
   1137             }
   1138             result = new Item(index++, key4);
   1139             put(result);
   1140         }
   1141         return result;
   1142     }
   1143 
   1144     /**
   1145      * Adds a handle to the constant pool of the class being build. Does nothing
   1146      * if the constant pool already contains a similar item. <i>This method is
   1147      * intended for {@link Attribute} sub classes, and is normally not needed by
   1148      * class generators or adapters.</i>
   1149      *
   1150      * @param tag
   1151      *            the kind of this handle. Must be {@link Opcodes#H_GETFIELD},
   1152      *            {@link Opcodes#H_GETSTATIC}, {@link Opcodes#H_PUTFIELD},
   1153      *            {@link Opcodes#H_PUTSTATIC}, {@link Opcodes#H_INVOKEVIRTUAL},
   1154      *            {@link Opcodes#H_INVOKESTATIC},
   1155      *            {@link Opcodes#H_INVOKESPECIAL},
   1156      *            {@link Opcodes#H_NEWINVOKESPECIAL} or
   1157      *            {@link Opcodes#H_INVOKEINTERFACE}.
   1158      * @param owner
   1159      *            the internal name of the field or method owner class.
   1160      * @param name
   1161      *            the name of the field or method.
   1162      * @param desc
   1163      *            the descriptor of the field or method.
   1164      * @return the index of a new or already existing method type reference
   1165      *         item.
   1166      */
   1167     public int newHandle(final int tag, final String owner, final String name,
   1168             final String desc) {
   1169         return newHandleItem(tag, owner, name, desc).index;
   1170     }
   1171 
   1172     /**
   1173      * Adds an invokedynamic reference to the constant pool of the class being
   1174      * build. Does nothing if the constant pool already contains a similar item.
   1175      * <i>This method is intended for {@link Attribute} sub classes, and is
   1176      * normally not needed by class generators or adapters.</i>
   1177      *
   1178      * @param name
   1179      *            name of the invoked method.
   1180      * @param desc
   1181      *            descriptor of the invoke method.
   1182      * @param bsm
   1183      *            the bootstrap method.
   1184      * @param bsmArgs
   1185      *            the bootstrap method constant arguments.
   1186      *
   1187      * @return a new or an already existing invokedynamic type reference item.
   1188      */
   1189     Item newInvokeDynamicItem(final String name, final String desc,
   1190             final Handle bsm, final Object... bsmArgs) {
   1191         // cache for performance
   1192         ByteVector bootstrapMethods = this.bootstrapMethods;
   1193         if (bootstrapMethods == null) {
   1194             bootstrapMethods = this.bootstrapMethods = new ByteVector();
   1195         }
   1196 
   1197         int position = bootstrapMethods.length; // record current position
   1198 
   1199         int hashCode = bsm.hashCode();
   1200         bootstrapMethods.putShort(newHandle(bsm.tag, bsm.owner, bsm.name,
   1201                 bsm.desc));
   1202 
   1203         int argsLength = bsmArgs.length;
   1204         bootstrapMethods.putShort(argsLength);
   1205 
   1206         for (int i = 0; i < argsLength; i++) {
   1207             Object bsmArg = bsmArgs[i];
   1208             hashCode ^= bsmArg.hashCode();
   1209             bootstrapMethods.putShort(newConst(bsmArg));
   1210         }
   1211 
   1212         byte[] data = bootstrapMethods.data;
   1213         int length = (1 + 1 + argsLength) << 1; // (bsm + argCount + arguments)
   1214         hashCode &= 0x7FFFFFFF;
   1215         Item result = items[hashCode % items.length];
   1216         loop: while (result != null) {
   1217             if (result.type != BSM || result.hashCode != hashCode) {
   1218                 result = result.next;
   1219                 continue;
   1220             }
   1221 
   1222             // because the data encode the size of the argument
   1223             // we don't need to test if these size are equals
   1224             int resultPosition = result.intVal;
   1225             for (int p = 0; p < length; p++) {
   1226                 if (data[position + p] != data[resultPosition + p]) {
   1227                     result = result.next;
   1228                     continue loop;
   1229                 }
   1230             }
   1231             break;
   1232         }
   1233 
   1234         int bootstrapMethodIndex;
   1235         if (result != null) {
   1236             bootstrapMethodIndex = result.index;
   1237             bootstrapMethods.length = position; // revert to old position
   1238         } else {
   1239             bootstrapMethodIndex = bootstrapMethodsCount++;
   1240             result = new Item(bootstrapMethodIndex);
   1241             result.set(position, hashCode);
   1242             put(result);
   1243         }
   1244 
   1245         // now, create the InvokeDynamic constant
   1246         key3.set(name, desc, bootstrapMethodIndex);
   1247         result = get(key3);
   1248         if (result == null) {
   1249             put122(INDY, bootstrapMethodIndex, newNameType(name, desc));
   1250             result = new Item(index++, key3);
   1251             put(result);
   1252         }
   1253         return result;
   1254     }
   1255 
   1256     /**
   1257      * Adds a field reference to the constant pool of the class being build.
   1258      * Does nothing if the constant pool already contains a similar item.
   1259      * <i>This method is intended for {@link Attribute} sub classes, and is
   1260      * normally not needed by class generators or adapters.</i>
   1261      *
   1262      * @param owner the internal name of the field's owner class.
   1263      * @param name the field's name.
   1264      * @param desc the field's descriptor.
   1265      * @return the index of a new or already existing field reference item.
   1266      */
   1267     public int newField(final String owner, final String name, final String desc)
   1268     {
   1269         key3.set(FIELD, owner, name, desc);
   1270         Item result = get(key3);
   1271         if (result == null) {
   1272             put122(FIELD, newClass(owner), newNameType(name, desc));
   1273             result = new Item(index++, key3);
   1274             put(result);
   1275         }
   1276         return result.index;
   1277     }
   1278 
   1279     /**
   1280      * Adds a method reference to the constant pool of the class being build.
   1281      * Does nothing if the constant pool already contains a similar item.
   1282      *
   1283      * @param owner the internal name of the method's owner class.
   1284      * @param name the method's name.
   1285      * @param desc the method's descriptor.
   1286      * @param itf <tt>true</tt> if <tt>owner</tt> is an interface.
   1287      * @return a new or already existing method reference item.
   1288      */
   1289     Item newMethodItem(
   1290         final String owner,
   1291         final String name,
   1292         final String desc,
   1293         final boolean itf)
   1294     {
   1295         int type = itf ? IMETH : METH;
   1296         key3.set(type, owner, name, desc);
   1297         Item result = get(key3);
   1298         if (result == null) {
   1299             put122(type, newClass(owner), newNameType(name, desc));
   1300             result = new Item(index++, key3);
   1301             put(result);
   1302         }
   1303         return result;
   1304     }
   1305 
   1306     /**
   1307      * Adds a method reference to the constant pool of the class being build.
   1308      * Does nothing if the constant pool already contains a similar item.
   1309      * <i>This method is intended for {@link Attribute} sub classes, and is
   1310      * normally not needed by class generators or adapters.</i>
   1311      *
   1312      * @param owner the internal name of the method's owner class.
   1313      * @param name the method's name.
   1314      * @param desc the method's descriptor.
   1315      * @param itf <tt>true</tt> if <tt>owner</tt> is an interface.
   1316      * @return the index of a new or already existing method reference item.
   1317      */
   1318     public int newMethod(
   1319         final String owner,
   1320         final String name,
   1321         final String desc,
   1322         final boolean itf)
   1323     {
   1324         return newMethodItem(owner, name, desc, itf).index;
   1325     }
   1326 
   1327     /**
   1328      * Adds an integer to the constant pool of the class being build. Does
   1329      * nothing if the constant pool already contains a similar item.
   1330      *
   1331      * @param value the int value.
   1332      * @return a new or already existing int item.
   1333      */
   1334     Item newInteger(final int value) {
   1335         key.set(value);
   1336         Item result = get(key);
   1337         if (result == null) {
   1338             pool.putByte(INT).putInt(value);
   1339             result = new Item(index++, key);
   1340             put(result);
   1341         }
   1342         return result;
   1343     }
   1344 
   1345     /**
   1346      * Adds a float to the constant pool of the class being build. Does nothing
   1347      * if the constant pool already contains a similar item.
   1348      *
   1349      * @param value the float value.
   1350      * @return a new or already existing float item.
   1351      */
   1352     Item newFloat(final float value) {
   1353         key.set(value);
   1354         Item result = get(key);
   1355         if (result == null) {
   1356             pool.putByte(FLOAT).putInt(Float.floatToIntBits(value));
   1357             result = new Item(index++, key);
   1358             put(result);
   1359         }
   1360         return result;
   1361     }
   1362 
   1363     /**
   1364      * Adds a long to the constant pool of the class being build. Does nothing
   1365      * if the constant pool already contains a similar item.
   1366      *
   1367      * @param value the long value.
   1368      * @return a new or already existing long item.
   1369      */
   1370     Item newLong(final long value) {
   1371         key.set(value);
   1372         Item result = get(key);
   1373         if (result == null) {
   1374             pool.putByte(LONG).putLong(value);
   1375             result = new Item(index, key);
   1376             put(result);
   1377             index += 2;
   1378         }
   1379         return result;
   1380     }
   1381 
   1382     /**
   1383      * Adds a double to the constant pool of the class being build. Does nothing
   1384      * if the constant pool already contains a similar item.
   1385      *
   1386      * @param value the double value.
   1387      * @return a new or already existing double item.
   1388      */
   1389     Item newDouble(final double value) {
   1390         key.set(value);
   1391         Item result = get(key);
   1392         if (result == null) {
   1393             pool.putByte(DOUBLE).putLong(Double.doubleToLongBits(value));
   1394             result = new Item(index, key);
   1395             put(result);
   1396             index += 2;
   1397         }
   1398         return result;
   1399     }
   1400 
   1401     /**
   1402      * Adds a string to the constant pool of the class being build. Does nothing
   1403      * if the constant pool already contains a similar item.
   1404      *
   1405      * @param value the String value.
   1406      * @return a new or already existing string item.
   1407      */
   1408     private Item newString(final String value) {
   1409         key2.set(STR, value, null, null);
   1410         Item result = get(key2);
   1411         if (result == null) {
   1412             pool.put12(STR, newUTF8(value));
   1413             result = new Item(index++, key2);
   1414             put(result);
   1415         }
   1416         return result;
   1417     }
   1418 
   1419     /**
   1420      * Adds a name and type to the constant pool of the class being build. Does
   1421      * nothing if the constant pool already contains a similar item. <i>This
   1422      * method is intended for {@link Attribute} sub classes, and is normally not
   1423      * needed by class generators or adapters.</i>
   1424      *
   1425      * @param name a name.
   1426      * @param desc a type descriptor.
   1427      * @return the index of a new or already existing name and type item.
   1428      */
   1429     public int newNameType(final String name, final String desc) {
   1430         key2.set(NAME_TYPE, name, desc, null);
   1431         Item result = get(key2);
   1432         if (result == null) {
   1433             put122(NAME_TYPE, newUTF8(name), newUTF8(desc));
   1434             result = new Item(index++, key2);
   1435             put(result);
   1436         }
   1437         return result.index;
   1438     }
   1439 
   1440     /**
   1441      * Returns the constant pool's hash table item which is equal to the given
   1442      * item.
   1443      *
   1444      * @param key a constant pool item.
   1445      * @return the constant pool's hash table item which is equal to the given
   1446      *         item, or <tt>null</tt> if there is no such item.
   1447      */
   1448     private Item get(final Item key) {
   1449         Item i = items[key.hashCode % items.length];
   1450         while (i != null && !key.isEqualTo(i)) {
   1451             i = i.next;
   1452         }
   1453         return i;
   1454     }
   1455 
   1456     /**
   1457      * Puts the given item in the constant pool's hash table. The hash table
   1458      * <i>must</i> not already contains this item.
   1459      *
   1460      * @param i the item to be added to the constant pool's hash table.
   1461      */
   1462     private void put(final Item i) {
   1463         if (index > threshold) {
   1464             int ll = items.length;
   1465             int nl = ll * 2 + 1;
   1466             Item[] newItems = new Item[nl];
   1467             for (int l = ll - 1; l >= 0; --l) {
   1468                 Item j = items[l];
   1469                 while (j != null) {
   1470                     int index = j.hashCode % newItems.length;
   1471                     Item k = j.next;
   1472                     j.next = newItems[index];
   1473                     newItems[index] = j;
   1474                     j = k;
   1475                 }
   1476             }
   1477             items = newItems;
   1478             threshold = (int) (nl * 0.75);
   1479         }
   1480         int index = i.hashCode % items.length;
   1481         i.next = items[index];
   1482         items[index] = i;
   1483     }
   1484 
   1485     /**
   1486      * Puts two bytes and one short into the constant pool.
   1487      *
   1488      * @param b a byte.
   1489      * @param s1 a short.
   1490      * @param s2 another short.
   1491      */
   1492     private void put112(final int b1, final int b2, final int s) {
   1493         pool.put11(b1, b2).putShort(s);
   1494     }
   1495 
   1496     /**
   1497      * Puts one byte and two shorts into the constant pool.
   1498      *
   1499      * @param b a byte.
   1500      * @param s1 a short.
   1501      * @param s2 another short.
   1502      */
   1503     private void put122(final int b, final int s1, final int s2) {
   1504         pool.put12(b, s1).putShort(s2);
   1505     }
   1506 }
   1507