001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 *  Unless required by applicable law or agreed to in writing, software
012 *  distributed under the License is distributed on an "AS IS" BASIS,
013 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 *  See the License for the specific language governing permissions and
015 *  limitations under the License.
016 */
017package org.apache.bcel.generic;
018
019import org.apache.bcel.Const;
020
021/**
022 * Super class for the x2y family of instructions.
023 */
024public abstract class ConversionInstruction extends Instruction implements TypedInstruction, StackProducer, StackConsumer {
025
026    /**
027     * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
028     */
029    ConversionInstruction() {
030    }
031
032    /**
033     * @param opcode opcode of instruction
034     */
035    protected ConversionInstruction(final short opcode) {
036        super(opcode, (short) 1);
037    }
038
039    /**
040     * @return type associated with the instruction
041     */
042    @Override
043    public Type getType(final ConstantPoolGen cp) {
044        final short opcode = super.getOpcode();
045        switch (opcode) {
046        case Const.D2I:
047        case Const.F2I:
048        case Const.L2I:
049            return Type.INT;
050        case Const.D2F:
051        case Const.I2F:
052        case Const.L2F:
053            return Type.FLOAT;
054        case Const.D2L:
055        case Const.F2L:
056        case Const.I2L:
057            return Type.LONG;
058        case Const.F2D:
059        case Const.I2D:
060        case Const.L2D:
061            return Type.DOUBLE;
062        case Const.I2B:
063            return Type.BYTE;
064        case Const.I2C:
065            return Type.CHAR;
066        case Const.I2S:
067            return Type.SHORT;
068        default: // Never reached
069            throw new ClassGenException("Unknown type " + opcode);
070        }
071    }
072}