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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   *  Unless required by applicable law or agreed to in writing, software
12   *  distributed under the License is distributed on an "AS IS" BASIS,
13   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   *  See the License for the specific language governing permissions and
15   *  limitations under the License.
16   *
17   */
18  package org.apache.bcel.generic;
19  
20  /**
21   * LDC2_W - Push long or double from constant pool
22   *
23   * <PRE>Stack: ... -&gt; ..., item.word1, item.word2</PRE>
24   *
25   * @version $Id: LDC2_W.html 1021978 2017-12-09 17:38:21Z ggregory $
26   */
27  public class LDC2_W extends CPInstruction implements PushInstruction {
28  
29      /**
30       * Empty constructor needed for Instruction.readInstruction.
31       * Not to be used otherwise.
32       */
33      LDC2_W() {
34      }
35  
36  
37      public LDC2_W(final int index) {
38          super(org.apache.bcel.Const.LDC2_W, index);
39      }
40  
41  
42      @Override
43      public Type getType( final ConstantPoolGen cpg ) {
44          switch (cpg.getConstantPool().getConstant(super.getIndex()).getTag()) {
45              case org.apache.bcel.Const.CONSTANT_Long:
46                  return Type.LONG;
47              case org.apache.bcel.Const.CONSTANT_Double:
48                  return Type.DOUBLE;
49              default: // Never reached
50                  throw new RuntimeException("Unknown constant type " + super.getOpcode());
51          }
52      }
53  
54  
55      public Number getValue( final ConstantPoolGen cpg ) {
56          final org.apache.bcel.classfile.Constant c = cpg.getConstantPool().getConstant(super.getIndex());
57          switch (c.getTag()) {
58              case org.apache.bcel.Const.CONSTANT_Long:
59                  return Long.valueOf(((org.apache.bcel.classfile.ConstantLong) c).getBytes());
60              case org.apache.bcel.Const.CONSTANT_Double:
61                  return new Double(((org.apache.bcel.classfile.ConstantDouble) c).getBytes());
62              default: // Never reached
63                  throw new RuntimeException("Unknown or invalid constant type at " + super.getIndex());
64          }
65      }
66  
67  
68      /**
69       * Call corresponding visitor method(s). The order is:
70       * Call visitor methods of implemented interfaces first, then
71       * call methods according to the class hierarchy in descending order,
72       * i.e., the most specific visitXXX() call comes last.
73       *
74       * @param v Visitor object
75       */
76      @Override
77      public void accept( final Visitor v ) {
78          v.visitStackProducer(this);
79          v.visitPushInstruction(this);
80          v.visitTypedInstruction(this);
81          v.visitCPInstruction(this);
82          v.visitLDC2_W(this);
83      }
84  }