001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.bcel.generic;
020
021/**
022 * LDC2_W - Push long or double from constant pool
023 *
024 * <pre>
025 * Stack: ... -&gt; ..., item.word1, item.word2
026 * </pre>
027 */
028public class LDC2_W extends CPInstruction implements PushInstruction {
029
030    /**
031     * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
032     */
033    LDC2_W() {
034    }
035
036    /**
037     * Constructs an LDC2_W instruction.
038     *
039     * @param index index into constant pool.
040     */
041    public LDC2_W(final int index) {
042        super(org.apache.bcel.Const.LDC2_W, index);
043    }
044
045    /**
046     * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call
047     * methods according to the class hierarchy in descending order, that is, the most specific visitXXX() call comes last.
048     *
049     * @param v Visitor object.
050     */
051    @Override
052    public void accept(final Visitor v) {
053        v.visitStackProducer(this);
054        v.visitPushInstruction(this);
055        v.visitTypedInstruction(this);
056        v.visitCPInstruction(this);
057        v.visitLDC2_W(this);
058    }
059
060    @Override
061    public Type getType(final ConstantPoolGen cpg) {
062        switch (cpg.getConstantPool().getConstant(super.getIndex()).getTag()) {
063        case org.apache.bcel.Const.CONSTANT_Long:
064            return Type.LONG;
065        case org.apache.bcel.Const.CONSTANT_Double:
066            return Type.DOUBLE;
067        default: // Never reached
068            throw new IllegalArgumentException("Unknown constant type " + super.getOpcode());
069        }
070    }
071
072    /**
073     * Gets the constant value from the constant pool.
074     *
075     * @param cpg constant pool generator.
076     * @return The constant value as a Number.
077     */
078    public Number getValue(final ConstantPoolGen cpg) {
079        final org.apache.bcel.classfile.Constant c = cpg.getConstantPool().getConstant(super.getIndex());
080        switch (c.getTag()) {
081        case org.apache.bcel.Const.CONSTANT_Long:
082            return Long.valueOf(((org.apache.bcel.classfile.ConstantLong) c).getBytes());
083        case org.apache.bcel.Const.CONSTANT_Double:
084            return Double.valueOf(((org.apache.bcel.classfile.ConstantDouble) c).getBytes());
085        default: // Never reached
086            throw new IllegalArgumentException("Unknown or invalid constant type at " + super.getIndex());
087        }
088    }
089}