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.commons.compress.harmony.unpack200.bytecode.forms;
018
019import org.apache.commons.compress.harmony.pack200.Pack200Exception;
020import org.apache.commons.compress.harmony.unpack200.SegmentConstantPool;
021import org.apache.commons.compress.harmony.unpack200.bytecode.ByteCode;
022import org.apache.commons.compress.harmony.unpack200.bytecode.ClassFileEntry;
023import org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager;
024
025/**
026 * This class implements the byte code form for those bytecodes which have class references (and only class references).
027 */
028public class ClassRefForm extends ReferenceForm {
029
030    protected boolean widened;
031
032    public ClassRefForm(final int opcode, final String name, final int[] rewrite) {
033        super(opcode, name, rewrite);
034    }
035
036    public ClassRefForm(final int opcode, final String name, final int[] rewrite, final boolean widened) {
037        this(opcode, name, rewrite);
038        this.widened = widened;
039    }
040
041    @Override
042    protected int getOffset(final OperandManager operandManager) {
043        return operandManager.nextClassRef();
044    }
045
046    @Override
047    protected int getPoolID() {
048        return SegmentConstantPool.CP_CLASS;
049    }
050
051    @Override
052    protected void setNestedEntries(final ByteCode byteCode, final OperandManager operandManager, final int offset) throws Pack200Exception {
053        // If the offset is not zero, proceed normally.
054        if (offset != 0) {
055            super.setNestedEntries(byteCode, operandManager, offset - 1);
056            return;
057        }
058        // If the offset is 0, ClassRefForms refer to
059        // the current class. Add that as the nested class.
060        // (This is true for all bc_classref forms in
061        // the spec except for multianewarray, which has
062        // its own form.)
063        final SegmentConstantPool globalPool = operandManager.globalConstantPool();
064        // How do I get this class?
065        final ClassFileEntry[] nested = { globalPool.getClassPoolEntry(operandManager.getCurrentClass()) };
066        byteCode.setNested(nested);
067        byteCode.setNestedPositions(new int[][] { { 0, 2 } });
068    }
069}