1 /*
   2  * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
   3  */
   4 /*
   5  * Licensed to the Apache Software Foundation (ASF) under one or more
   6  * contributor license agreements.  See the NOTICE file distributed with
   7  * this work for additional information regarding copyright ownership.
   8  * The ASF licenses this file to You under the Apache License, Version 2.0
   9  * (the "License"); you may not use this file except in compliance with
  10  * the License.  You may obtain a copy of the License at
  11  *
  12  *      http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing, software
  15  * distributed under the License is distributed on an "AS IS" BASIS,
  16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17  * See the License for the specific language governing permissions and
  18  * limitations under the License.
  19  */
  20 
  21 package com.sun.org.apache.bcel.internal.generic;
  22 
  23 /**
  24  * DCONST - Push 0.0 or 1.0, other values cause an exception
  25  *
  26  * <PRE>Stack: ... -&gt; ..., </PRE>
  27  *
  28  * @version $Id: DCONST.java 1747278 2016-06-07 17:28:43Z britter $
  29  */
  30 public class DCONST extends Instruction implements ConstantPushInstruction {
  31 
  32     private double value;
  33 
  34 
  35     /**
  36      * Empty constructor needed for the Class.newInstance() statement in
  37      * Instruction.readInstruction(). Not to be used otherwise.
  38      */
  39     DCONST() {
  40     }
  41 
  42 
  43     public DCONST(final double f) {
  44         super(com.sun.org.apache.bcel.internal.Const.DCONST_0, (short) 1);
  45         if (f == 0.0) {
  46             super.setOpcode(com.sun.org.apache.bcel.internal.Const.DCONST_0);
  47         } else if (f == 1.0) {
  48             super.setOpcode(com.sun.org.apache.bcel.internal.Const.DCONST_1);
  49         } else {
  50             throw new ClassGenException("DCONST can be used only for 0.0 and 1.0: " + f);
  51         }
  52         value = f;
  53     }
  54 
  55 
  56     @Override
  57     public Number getValue() {
  58         return new Double(value);
  59     }
  60 
  61 
  62     /** @return Type.DOUBLE
  63      */
  64     @Override
  65     public Type getType( final ConstantPoolGen cp ) {
  66         return Type.DOUBLE;
  67     }
  68 
  69 
  70     /**
  71      * Call corresponding visitor method(s). The order is:
  72      * Call visitor methods of implemented interfaces first, then
  73      * call methods according to the class hierarchy in descending order,
  74      * i.e., the most specific visitXXX() call comes last.
  75      *
  76      * @param v Visitor object
  77      */
  78     @Override
  79     public void accept( final Visitor v ) {
  80         v.visitPushInstruction(this);
  81         v.visitStackProducer(this);
  82         v.visitTypedInstruction(this);
  83         v.visitConstantPushInstruction(this);
  84         v.visitDCONST(this);
  85     }
  86 }