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 * FCONST - Push 0.0, 1.0 or 2.0, other values cause an exception
023 *
024 * <PRE>
025 * Stack: ... -&gt; ...,
026 * </PRE>
027 */
028public class FCONST extends Instruction implements ConstantPushInstruction {
029
030    private final float value;
031
032    /**
033     * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
034     */
035    FCONST() {
036        this(0);
037    }
038
039    /**
040     * Constructs an FCONST instruction.
041     *
042     * @param f the float value.
043     */
044    public FCONST(final float f) {
045        super(org.apache.bcel.Const.FCONST_0, (short) 1);
046        if (f == 0.0) {
047            super.setOpcode(org.apache.bcel.Const.FCONST_0);
048        } else if (f == 1.0) {
049            super.setOpcode(org.apache.bcel.Const.FCONST_1);
050        } else if (f == 2.0) {
051            super.setOpcode(org.apache.bcel.Const.FCONST_2);
052        } else {
053            throw new ClassGenException("FCONST can be used only for 0.0, 1.0 and 2.0: " + f);
054        }
055        value = f;
056    }
057
058    /**
059     * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call
060     * methods according to the class hierarchy in descending order, that is, the most specific visitXXX() call comes last.
061     *
062     * @param v Visitor object.
063     */
064    @Override
065    public void accept(final Visitor v) {
066        v.visitPushInstruction(this);
067        v.visitStackProducer(this);
068        v.visitTypedInstruction(this);
069        v.visitConstantPushInstruction(this);
070        v.visitFCONST(this);
071    }
072
073    /**
074     * @return Type.FLOAT.
075     */
076    @Override
077    public Type getType(final ConstantPoolGen cp) {
078        return Type.FLOAT;
079    }
080
081    @Override
082    public Number getValue() {
083        return Float.valueOf(value);
084    }
085}