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    1   /*
    2    * Copyright  2000-2004 The Apache Software Foundation
    3    *
    4    *  Licensed under the Apache License, Version 2.0 (the "License");
    5    *  you may not use this file except in compliance with the License.
    6    *  You may obtain a copy of the License at
    7    *
    8    *      http://www.apache.org/licenses/LICENSE-2.0
    9    *
    10   *  Unless required by applicable law or agreed to in writing, software
    11   *  distributed under the License is distributed on an "AS IS" BASIS,
    12   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   *  See the License for the specific language governing permissions and
    14   *  limitations under the License.
    15   *
    16   */
    17  package org.apache.bcel.generic;
    18
    19  /***
    20   * LDC2_W - Push long or double from constant pool
    21   *
    22   * <PRE>Stack: ... -&gt; ..., item.word1, item.word2</PRE>
    23   *
    24   * @version $Id: LDC2_W.java 386056 2006-03-15 11:31:56Z tcurdt $
    25   * @author  <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A>
    26   */
    27  public class LDC2_W extends CPInstruction implements PushInstruction, TypedInstruction {
    28
    29      /***
    30       * Empty constructor needed for the Class.newInstance() statement in
    31       * Instruction.readInstruction(). Not to be used otherwise.
    32       */
    33      LDC2_W() {
    34      }
    35
    36
    37      public LDC2_W(int index) {
    38          super(org.apache.bcel.Constants.LDC2_W, index);
    39      }
    40
    41
    42      public Type getType( ConstantPoolGen cpg ) {
    43          switch (cpg.getConstantPool().getConstant(index).getTag()) {
    44              case org.apache.bcel.Constants.CONSTANT_Long:
    45                  return Type.LONG;
    46              case org.apache.bcel.Constants.CONSTANT_Double:
    47                  return Type.DOUBLE;
    48              default: // Never reached
    49                  throw new RuntimeException("Unknown constant type " + opcode);
    50          }
    51      }
    52
    53
    54      public Number getValue( ConstantPoolGen cpg ) {
    55          org.apache.bcel.classfile.Constant c = cpg.getConstantPool().getConstant(index);
    56          switch (c.getTag()) {
    57              case org.apache.bcel.Constants.CONSTANT_Long:
    58                  return new Long(((org.apache.bcel.classfile.ConstantLong) c).getBytes());
    59              case org.apache.bcel.Constants.CONSTANT_Double:
    60                  return new Double(((org.apache.bcel.classfile.ConstantDouble) c).getBytes());
    61              default: // Never reached
    62                  throw new RuntimeException("Unknown or invalid constant type at " + index);
    63          }
    64      }
    65
    66
    67      /***
    68       * Call corresponding visitor method(s). The order is:
    69       * Call visitor methods of implemented interfaces first, then
    70       * call methods according to the class hierarchy in descending order,
    71       * i.e., the most specific visitXXX() call comes last.
    72       *
    73       * @param v Visitor object
    74       */
    75      public void accept( Visitor v ) {
    76          v.visitStackProducer(this);
    77          v.visitPushInstruction(this);
    78          v.visitTypedInstruction(this);
    79          v.visitCPInstruction(this);
    80          v.visitLDC2_W(this);
    81      }
    82  }