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    1   /*
    2    * Copyright  2000-2004 The Apache Software Foundation
    3    *
    4    *  Licensed under the Apache License, Version 2.0 (the "License");
    5    *  you may not use this file except in compliance with the License.
    6    *  You may obtain a copy of the License at
    7    *
    8    *      http://www.apache.org/licenses/LICENSE-2.0
    9    *
    10   *  Unless required by applicable law or agreed to in writing, software
    11   *  distributed under the License is distributed on an "AS IS" BASIS,
    12   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   *  See the License for the specific language governing permissions and
    14   *  limitations under the License.
    15   *
    16   */
    17  package org.apache.bcel.generic;
    18
    19  /***
    20   * DCONST - Push 0.0 or 1.0, other values cause an exception
    21   *
    22   * <PRE>Stack: ... -&gt; ..., </PRE>
    23   *
    24   * @version $Id: DCONST.java 386056 2006-03-15 11:31:56Z tcurdt $
    25   * @author  <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A>
    26   */
    27  public class DCONST extends Instruction implements ConstantPushInstruction, TypedInstruction {
    28
    29      private double value;
    30
    31
    32      /***
    33       * Empty constructor needed for the Class.newInstance() statement in
    34       * Instruction.readInstruction(). Not to be used otherwise.
    35       */
    36      DCONST() {
    37      }
    38
    39
    40      public DCONST(double f) {
    41          super(org.apache.bcel.Constants.DCONST_0, (short) 1);
    42          if (f == 0.0) {
    43              opcode = org.apache.bcel.Constants.DCONST_0;
    44          } else if (f == 1.0) {
    45              opcode = org.apache.bcel.Constants.DCONST_1;
    46          } else {
    47              throw new ClassGenException("DCONST can be used only for 0.0 and 1.0: " + f);
    48          }
    49          value = f;
    50      }
    51
    52
    53      public Number getValue() {
    54          return new Double(value);
    55      }
    56
    57
    58      /*** @return Type.DOUBLE
    59       */
    60      public Type getType( ConstantPoolGen cp ) {
    61          return Type.DOUBLE;
    62      }
    63
    64
    65      /***
    66       * Call corresponding visitor method(s). The order is:
    67       * Call visitor methods of implemented interfaces first, then
    68       * call methods according to the class hierarchy in descending order,
    69       * i.e., the most specific visitXXX() call comes last.
    70       *
    71       * @param v Visitor object
    72       */
    73      public void accept( Visitor v ) {
    74          v.visitPushInstruction(this);
    75          v.visitStackProducer(this);
    76          v.visitTypedInstruction(this);
    77          v.visitConstantPushInstruction(this);
    78          v.visitDCONST(this);
    79      }
    80  }