    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one
    003 * or more contributor license agreements.  See the NOTICE file
    004 * distributed with this work for additional information
    005 * regarding copyright ownership.  The ASF licenses this file
    006 * to you under the Apache License, Version 2.0 (the
    007 * "License"); you may not use this file except in compliance
    008 * with the License.  You may obtain a copy of the License at
    009 *
    010 *   https://www.apache.org/licenses/LICENSE-2.0
    011 *
    012 * Unless required by applicable law or agreed to in writing,
    013 * software distributed under the License is distributed on an
    014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    015 * KIND, either express or implied.  See the License for the
    016 * specific language governing permissions and limitations
    017 * under the License.
    018 */
    019package org.apache.bcel.generic;
    020
    021/**
    022 * DCONST - Push 0.0 or 1.0, other values cause an exception
    023 *
    024 * <PRE>
    025 * Stack: ... -&gt; ...,
    026 * </PRE>
    027 */
    028public class DCONST extends Instruction implements ConstantPushInstruction {
    029
    030    private final double value;
    031
    032    /**
    033     * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
    034     */
    035    DCONST() {
    036        this(0);
    037    }
    038
    039    public DCONST(final double f) {
    040        super(org.apache.bcel.Const.DCONST_0, (short) 1);
    041        if (f == 0.0) {
    042            super.setOpcode(org.apache.bcel.Const.DCONST_0);
    043        } else if (f == 1.0) {
    044            super.setOpcode(org.apache.bcel.Const.DCONST_1);
    045        } else {
    046            throw new ClassGenException("DCONST can be used only for 0.0 and 1.0: " + f);
    047        }
    048        value = f;
    049    }
    050
    051    /**
    052     * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call
    053     * methods according to the class hierarchy in descending order, i.e., the most specific visitXXX() call comes last.
    054     *
    055     * @param v Visitor object
    056     */
    057    @Override
    058    public void accept(final Visitor v) {
    059        v.visitPushInstruction(this);
    060        v.visitStackProducer(this);
    061        v.visitTypedInstruction(this);
    062        v.visitConstantPushInstruction(this);
    063        v.visitDCONST(this);
    064    }
    065
    066    /**
    067     * @return Type.DOUBLE
    068     */
    069    @Override
    070    public Type getType(final ConstantPoolGen cp) {
    071        return Type.DOUBLE;
    072    }
    073
    074    @Override
    075    public Number getValue() {
    076        return Double.valueOf(value);
    077    }
    078}