    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 *
    017 */
    018package org.apache.bcel.generic;
    019
    020import org.apache.bcel.Const;
    021import org.apache.bcel.ExceptionConst;
    022
    023/**
    024 * Super class for the xRETURN family of instructions.
    025 *
    026 */
    027public abstract class ReturnInstruction extends Instruction implements ExceptionThrower,
    028        TypedInstruction, StackConsumer {
    029
    030    /**
    031     * Empty constructor needed for Instruction.readInstruction.
    032     * Not to be used otherwise.
    033     */
    034    ReturnInstruction() {
    035    }
    036
    037
    038    /**
    039     * @param opcode of instruction
    040     */
    041    protected ReturnInstruction(final short opcode) {
    042        super(opcode, (short) 1);
    043    }
    044
    045
    046    public Type getType() {
    047        final short _opcode = super.getOpcode();
    048        switch (_opcode) {
    049            case Const.IRETURN:
    050                return Type.INT;
    051            case Const.LRETURN:
    052                return Type.LONG;
    053            case Const.FRETURN:
    054                return Type.FLOAT;
    055            case Const.DRETURN:
    056                return Type.DOUBLE;
    057            case Const.ARETURN:
    058                return Type.OBJECT;
    059            case Const.RETURN:
    060                return Type.VOID;
    061            default: // Never reached
    062                throw new ClassGenException("Unknown type " + _opcode);
    063        }
    064    }
    065
    066
    067    @Override
    068    public Class<?>[] getExceptions() {
    069        return new Class[] {
    070            ExceptionConst.ILLEGAL_MONITOR_STATE
    071        };
    072    }
    073
    074
    075    /** @return type associated with the instruction
    076     */
    077    @Override
    078    public Type getType( final ConstantPoolGen cp ) {
    079        return getType();
    080    }
    081}