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.bytecode.ByteCode;
021import org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager;
022
023/**
024 * Some bytecodes (such as (a)ldc, fldc and ildc) have single- byte references to the class pool. This class is the
025 * abstract superclass of those classes.
026 */
027public abstract class SingleByteReferenceForm extends ReferenceForm {
028
029    protected boolean widened;
030
031    public SingleByteReferenceForm(final int opcode, final String name, final int[] rewrite) {
032        super(opcode, name, rewrite);
033    }
034
035    @Override
036    protected abstract int getOffset(OperandManager operandManager);
037
038    @Override
039    protected abstract int getPoolID();
040
041    @Override
042    protected void setNestedEntries(final ByteCode byteCode, final OperandManager operandManager, final int offset)
043        throws Pack200Exception {
044        super.setNestedEntries(byteCode, operandManager, offset);
045        if (widened) {
046            byteCode.setNestedPositions(new int[][] {{0, 2}});
047        } else {
048            byteCode.setNestedPositions(new int[][] {{0, 1}});
049        }
050    }
051
052    @Override
053    public boolean nestedMustStartClassPool() {
054        return !widened;
055    }
056}