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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   * FCONST - Push 0.0, 1.0 or 2.0, other values cause an exception
23   *
24   * <PRE>
25   * Stack: ... -&gt; ...,
26   * </PRE>
27   */
28  public class FCONST extends Instruction implements ConstantPushInstruction {
29  
30      private final float value;
31  
32      /**
33       * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
34       */
35      FCONST() {
36          this(0);
37      }
38  
39      /**
40       * Constructs an FCONST instruction.
41       *
42       * @param f the float value.
43       */
44      public FCONST(final float f) {
45          super(org.apache.bcel.Const.FCONST_0, (short) 1);
46          if (f == 0.0) {
47              super.setOpcode(org.apache.bcel.Const.FCONST_0);
48          } else if (f == 1.0) {
49              super.setOpcode(org.apache.bcel.Const.FCONST_1);
50          } else if (f == 2.0) {
51              super.setOpcode(org.apache.bcel.Const.FCONST_2);
52          } else {
53              throw new ClassGenException("FCONST can be used only for 0.0, 1.0 and 2.0: " + f);
54          }
55          value = f;
56      }
57  
58      /**
59       * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call
60       * methods according to the class hierarchy in descending order, that is, the most specific visitXXX() call comes last.
61       *
62       * @param v Visitor object.
63       */
64      @Override
65      public void accept(final Visitor v) {
66          v.visitPushInstruction(this);
67          v.visitStackProducer(this);
68          v.visitTypedInstruction(this);
69          v.visitConstantPushInstruction(this);
70          v.visitFCONST(this);
71      }
72  
73      /**
74       * @return Type.FLOAT.
75       */
76      @Override
77      public Type getType(final ConstantPoolGen cp) {
78          return Type.FLOAT;
79      }
80  
81      @Override
82      public Number getValue() {
83          return Float.valueOf(value);
84      }
85  }