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
019/**
020 * Super class for stack operations like DUP and POP.
021 */
022public abstract class StackInstruction extends Instruction {
023
024    /**
025     * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
026     */
027    StackInstruction() {
028    }
029
030    /**
031     * @param opcode instruction opcode
032     */
033    protected StackInstruction(final short opcode) {
034        super(opcode, (short) 1);
035    }
036
037    /**
038     * @return Type.UNKNOWN
039     */
040    public Type getType(final ConstantPoolGen cp) {
041        return Type.UNKNOWN;
042    }
043}