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 * @version $Id: LDC2_W.java 1749603 2016-06-21 20:50:19Z ggregory $
026 */
027public class LDC2_W extends CPInstruction implements PushInstruction {
028
029    /**
030     * Empty constructor needed for the Class.newInstance() statement in
031     * Instruction.readInstruction(). Not to be used otherwise.
032     */
033    LDC2_W() {
034    }
035
036
037    public LDC2_W(final int index) {
038        super(org.apache.bcel.Const.LDC2_W, index);
039    }
040
041
042    @Override
043    public Type getType( final ConstantPoolGen cpg ) {
044        switch (cpg.getConstantPool().getConstant(super.getIndex()).getTag()) {
045            case org.apache.bcel.Const.CONSTANT_Long:
046                return Type.LONG;
047            case org.apache.bcel.Const.CONSTANT_Double:
048                return Type.DOUBLE;
049            default: // Never reached
050                throw new RuntimeException("Unknown constant type " + super.getOpcode());
051        }
052    }
053
054
055    public Number getValue( final ConstantPoolGen cpg ) {
056        final org.apache.bcel.classfile.Constant c = cpg.getConstantPool().getConstant(super.getIndex());
057        switch (c.getTag()) {
058            case org.apache.bcel.Const.CONSTANT_Long:
059                return Long.valueOf(((org.apache.bcel.classfile.ConstantLong) c).getBytes());
060            case org.apache.bcel.Const.CONSTANT_Double:
061                return new Double(((org.apache.bcel.classfile.ConstantDouble) c).getBytes());
062            default: // Never reached
063                throw new RuntimeException("Unknown or invalid constant type at " + super.getIndex());
064        }
065    }
066
067
068    /**
069     * Call corresponding visitor method(s). The order is:
070     * Call visitor methods of implemented interfaces first, then
071     * call methods according to the class hierarchy in descending order,
072     * i.e., the most specific visitXXX() call comes last.
073     *
074     * @param v Visitor object
075     */
076    @Override
077    public void accept( final Visitor v ) {
078        v.visitStackProducer(this);
079        v.visitPushInstruction(this);
080        v.visitTypedInstruction(this);
081        v.visitCPInstruction(this);
082        v.visitLDC2_W(this);
083    }
084}