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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   https://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.apache.bcel.generic;
20  
21  /**
22   * LDC2_W - Push long or double from constant pool
23   *
24   * <pre>
25   * Stack: ... -&gt; ..., item.word1, item.word2
26   * </pre>
27   */
28  public class LDC2_W extends CPInstruction implements PushInstruction {
29  
30      /**
31       * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
32       */
33      LDC2_W() {
34      }
35  
36      /**
37       * Constructs an LDC2_W instruction.
38       *
39       * @param index index into constant pool.
40       */
41      public LDC2_W(final int index) {
42          super(org.apache.bcel.Const.LDC2_W, index);
43      }
44  
45      /**
46       * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call
47       * methods according to the class hierarchy in descending order, that is, the most specific visitXXX() call comes last.
48       *
49       * @param v Visitor object.
50       */
51      @Override
52      public void accept(final Visitor v) {
53          v.visitStackProducer(this);
54          v.visitPushInstruction(this);
55          v.visitTypedInstruction(this);
56          v.visitCPInstruction(this);
57          v.visitLDC2_W(this);
58      }
59  
60      @Override
61      public Type getType(final ConstantPoolGen cpg) {
62          switch (cpg.getConstantPool().getConstant(super.getIndex()).getTag()) {
63          case org.apache.bcel.Const.CONSTANT_Long:
64              return Type.LONG;
65          case org.apache.bcel.Const.CONSTANT_Double:
66              return Type.DOUBLE;
67          default: // Never reached
68              throw new IllegalArgumentException("Unknown constant type " + super.getOpcode());
69          }
70      }
71  
72      /**
73       * Gets the constant value from the constant pool.
74       *
75       * @param cpg constant pool generator.
76       * @return The constant value as a Number.
77       */
78      public Number getValue(final ConstantPoolGen cpg) {
79          final org.apache.bcel.classfile.Constant c = cpg.getConstantPool().getConstant(super.getIndex());
80          switch (c.getTag()) {
81          case org.apache.bcel.Const.CONSTANT_Long:
82              return Long.valueOf(((org.apache.bcel.classfile.ConstantLong) c).getBytes());
83          case org.apache.bcel.Const.CONSTANT_Double:
84              return Double.valueOf(((org.apache.bcel.classfile.ConstantDouble) c).getBytes());
85          default: // Never reached
86              throw new IllegalArgumentException("Unknown or invalid constant type at " + super.getIndex());
87          }
88      }
89  }