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