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.commons.compress.harmony.unpack200.bytecode.forms;
020
021import org.apache.commons.compress.harmony.pack200.Pack200Exception;
022import org.apache.commons.compress.harmony.unpack200.SegmentConstantPool;
023import org.apache.commons.compress.harmony.unpack200.bytecode.ByteCode;
024import org.apache.commons.compress.harmony.unpack200.bytecode.ClassFileEntry;
025import org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager;
026
027/**
028 * This class implements the byte code form for those bytecodes which have string references (and only string references).
029 */
030public class StringRefForm extends SingleByteReferenceForm {
031
032    /**
033     * Constructs a new instance with the specified opcode, name, operandType and rewrite.
034     *
035     * @param opcode  index corresponding to the opcode's value.
036     * @param name    String printable name of the opcode.
037     * @param rewrite Operand positions (which will later be rewritten in ByteCodes) are indicated by -1.
038     */
039    public StringRefForm(final int opcode, final String name, final int[] rewrite) {
040        super(opcode, name, rewrite);
041    }
042
043    /**
044     * Constructs a new instance with the specified opcode, name, operandType and rewrite.
045     *
046     * @param opcode  index corresponding to the opcode's value.
047     * @param name    String printable name of the opcode.
048     * @param rewrite Operand positions (which will later be rewritten in ByteCodes) are indicated by -1.
049     * @param widened TODO.
050     */
051    public StringRefForm(final int opcode, final String name, final int[] rewrite, final boolean widened) {
052        this(opcode, name, rewrite);
053        this.widened = widened;
054    }
055
056    @Override
057    protected int getOffset(final OperandManager operandManager) {
058        return operandManager.nextStringRef();
059    }
060
061    @Override
062    protected int getPoolID() {
063        return SegmentConstantPool.CP_STRING;
064    }
065
066    @Override
067    protected void setNestedEntries(final ByteCode byteCode, final OperandManager operandManager, final int offset) throws Pack200Exception {
068        final SegmentConstantPool globalPool = operandManager.globalConstantPool();
069        final ClassFileEntry[] nested = { globalPool.getValue(getPoolID(), offset) };
070        byteCode.setNested(nested);
071        if (widened) {
072            byteCode.setNestedPositions(new int[][] { { 0, 2 } });
073        } else {
074            byteCode.setNestedPositions(new int[][] { { 0, 1 } });
075        }
076    }
077}