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
021import org.apache.bcel.Const;
022
023/**
024 * Superclass for the x2y family of instructions.
025 */
026public abstract class ConversionInstruction extends Instruction implements TypedInstruction, StackProducer, StackConsumer {
027
028    /**
029     * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
030     */
031    ConversionInstruction() {
032    }
033
034    /**
035     * Constructs a ConversionInstruction.
036     *
037     * @param opcode opcode of instruction.
038     */
039    protected ConversionInstruction(final short opcode) {
040        super(opcode, (short) 1);
041    }
042
043    /**
044     * Gets the type associated with the instruction.
045     *
046     * @return type associated with the instruction.
047     */
048    @Override
049    public Type getType(final ConstantPoolGen cp) {
050        final short opcode = super.getOpcode();
051        switch (opcode) {
052        case Const.D2I:
053        case Const.F2I:
054        case Const.L2I:
055            return Type.INT;
056        case Const.D2F:
057        case Const.I2F:
058        case Const.L2F:
059            return Type.FLOAT;
060        case Const.D2L:
061        case Const.F2L:
062        case Const.I2L:
063            return Type.LONG;
064        case Const.F2D:
065        case Const.I2D:
066        case Const.L2D:
067            return Type.DOUBLE;
068        case Const.I2B:
069            return Type.BYTE;
070        case Const.I2C:
071            return Type.CHAR;
072        case Const.I2S:
073            return Type.SHORT;
074        default: // Never reached
075            throw new ClassGenException("Unknown type " + opcode);
076        }
077    }
078}