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 * LDC2_W - Push long or double from constant pool
022 *
023 * <PRE>Stack: ... -&gt; ..., item.word1, item.word2</PRE>
024 *
025 */
026public class LDC2_W extends CPInstruction implements PushInstruction {
027
028    /**
029     * Empty constructor needed for Instruction.readInstruction.
030     * Not to be used otherwise.
031     */
032    LDC2_W() {
033    }
034
035
036    public LDC2_W(final int index) {
037        super(org.apache.bcel.Const.LDC2_W, index);
038    }
039
040
041    @Override
042    public Type getType( final ConstantPoolGen cpg ) {
043        switch (cpg.getConstantPool().getConstant(super.getIndex()).getTag()) {
044            case org.apache.bcel.Const.CONSTANT_Long:
045                return Type.LONG;
046            case org.apache.bcel.Const.CONSTANT_Double:
047                return Type.DOUBLE;
048            default: // Never reached
049                throw new IllegalArgumentException("Unknown constant type " + super.getOpcode());
050        }
051    }
052
053
054    public Number getValue( final ConstantPoolGen cpg ) {
055        final org.apache.bcel.classfile.Constant c = cpg.getConstantPool().getConstant(super.getIndex());
056        switch (c.getTag()) {
057            case org.apache.bcel.Const.CONSTANT_Long:
058                return Long.valueOf(((org.apache.bcel.classfile.ConstantLong) c).getBytes());
059            case org.apache.bcel.Const.CONSTANT_Double:
060                return new Double(((org.apache.bcel.classfile.ConstantDouble) c).getBytes());
061            default: // Never reached
062                throw new IllegalArgumentException("Unknown or invalid constant type at " + super.getIndex());
063        }
064    }
065
066
067    /**
068     * Call corresponding visitor method(s). The order is:
069     * Call visitor methods of implemented interfaces first, then
070     * call methods according to the class hierarchy in descending order,
071     * i.e., the most specific visitXXX() call comes last.
072     *
073     * @param v Visitor object
074     */
075    @Override
076    public void accept( final Visitor v ) {
077        v.visitStackProducer(this);
078        v.visitPushInstruction(this);
079        v.visitTypedInstruction(this);
080        v.visitCPInstruction(this);
081        v.visitLDC2_W(this);
082    }
083}