    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.CPClass;
    025import org.apache.commons.compress.harmony.unpack200.bytecode.ClassFileEntry;
    026import org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager;
    027
    028/**
    029 * 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.
    030 * To allow the sender to create instances of either a specified class (which then becomes the new class) or the last used new class.
    031 */
    032public class NewClassRefForm extends ClassRefForm {
    033
    034    /**
    035     * Constructs a new instance with the specified opcode, name, operandType and rewrite.
    036     *
    037     * @param opcode  index corresponding to the opcode's value.
    038     * @param name    String printable name of the opcode.
    039     * @param rewrite Operand positions (which will later be rewritten in ByteCodes) are indicated by -1.
    040     */
    041    public NewClassRefForm(final int opcode, final String name, final int[] rewrite) {
    042        super(opcode, name, rewrite);
    043    }
    044
    045    /*
    046     * (non-Javadoc)
    047     *
    048     * @see org.apache.commons.compress.harmony.unpack200.bytecode.forms.ReferenceForm#setByteCodeOperands(org.apache.commons
    049     * .compress.harmony.unpack200.bytecode.ByteCode, org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager)
    050     */
    051    @Override
    052    public void setByteCodeOperands(final ByteCode byteCode, final OperandManager operandManager, final int codeLength) throws Pack200Exception {
    053        final int offset = getOffset(operandManager);
    054        if (offset == 0) {
    055            // Use current class
    056            final SegmentConstantPool globalPool = operandManager.globalConstantPool();
    057            final ClassFileEntry[] nested = { globalPool.getClassPoolEntry(operandManager.getCurrentClass()) };
    058            byteCode.setNested(nested);
    059            byteCode.setNestedPositions(new int[][] { { 0, 2 } });
    060        } else {
    061            // Look up the class in the classpool
    062            try {
    063                // Parent takes care of subtracting one from offset
    064                // to adjust for 1-based global pool
    065                setNestedEntries(byteCode, operandManager, offset);
    066            } catch (final Pack200Exception ex) {
    067                throw new Error("Got a pack200 exception. What to do?");
    068            }
    069        }
    070        operandManager.setNewClass(((CPClass) byteCode.getNestedClassFileEntries()[0]).getName());
    071    }
    072}