    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
    020/**
    021 * Super class for stack operations like DUP and POP.
    022 *
    023 * @version $Id$
    024 */
    025public abstract class StackInstruction extends Instruction {
    026
    027    /**
    028     * Empty constructor needed for Instruction.readInstruction.
    029     * Not to be used otherwise.
    030     */
    031    StackInstruction() {
    032    }
    033
    034
    035    /**
    036     * @param opcode instruction opcode
    037     */
    038    protected StackInstruction(final short opcode) {
    039        super(opcode, (short) 1);
    040    }
    041
    042
    043    /** @return Type.UNKNOWN
    044     */
    045    public Type getType( final ConstantPoolGen cp ) {
    046        return Type.UNKNOWN;
    047    }
    048}