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.CPClass;
023import org.apache.commons.compress.harmony.unpack200.bytecode.ClassFileEntry;
024import org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager;
025
026/**
027 * This class is an extension of the ClassRefForm. It has two purposes: 1. To keep track of the last type used in a new() instruction in the current class. 2.
028 * To allow the sender to create instances of either a specified class (which then becomes the new class) or the last used new class.
029 */
030public class NewClassRefForm extends ClassRefForm {
031
032    public NewClassRefForm(final int opcode, final String name, final int[] rewrite) {
033        super(opcode, name, rewrite);
034    }
035
036    /*
037     * (non-Javadoc)
038     *
039     * @see org.apache.commons.compress.harmony.unpack200.bytecode.forms.ReferenceForm#setByteCodeOperands(org.apache.commons
040     * .compress.harmony.unpack200.bytecode.ByteCode, org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager)
041     */
042    @Override
043    public void setByteCodeOperands(final ByteCode byteCode, final OperandManager operandManager, final int codeLength) {
044        final int offset = getOffset(operandManager);
045        if (offset == 0) {
046            // Use current class
047            final SegmentConstantPool globalPool = operandManager.globalConstantPool();
048            final ClassFileEntry[] nested = { globalPool.getClassPoolEntry(operandManager.getCurrentClass()) };
049            byteCode.setNested(nested);
050            byteCode.setNestedPositions(new int[][] { { 0, 2 } });
051        } else {
052            // Look up the class in the classpool
053            try {
054                // Parent takes care of subtracting one from offset
055                // to adjust for 1-based global pool
056                setNestedEntries(byteCode, operandManager, offset);
057            } catch (final Pack200Exception ex) {
058                throw new Error("Got a pack200 exception. What to do?");
059            }
060        }
061        operandManager.setNewClass(((CPClass) byteCode.getNestedClassFileEntries()[0]).getName());
062    }
063}