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.bytecode.ByteCode; 023import org.apache.commons.compress.harmony.unpack200.bytecode.OperandManager; 024 025/** 026 * Some bytecodes (such as (a)ldc, fldc and ildc) have single-byte references to the class pool. This class is the abstract superclass of those classes. 027 */ 028public abstract class SingleByteReferenceForm extends ReferenceForm { 029 030 protected boolean widened; 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 SingleByteReferenceForm(final int opcode, final String name, final int[] rewrite) { 040 super(opcode, name, rewrite); 041 } 042 043 @Override 044 protected abstract int getOffset(OperandManager operandManager); 045 046 @Override 047 protected abstract int getPoolID(); 048 049 @Override 050 public boolean nestedMustStartClassPool() { 051 return !widened; 052 } 053 054 @Override 055 protected void setNestedEntries(final ByteCode byteCode, final OperandManager operandManager, final int offset) throws Pack200Exception { 056 super.setNestedEntries(byteCode, operandManager, offset); 057 if (widened) { 058 byteCode.setNestedPositions(new int[][] { { 0, 2 } }); 059 } else { 060 byteCode.setNestedPositions(new int[][] { { 0, 1 } }); 061 } 062 } 063}