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;
018
019import java.io.DataOutputStream;
020import java.io.IOException;
021import java.util.Arrays;
022
023/**
024 * Exceptions class file attribute
025 */
026public class ExceptionsAttribute extends Attribute {
027
028    private static CPUTF8 attributeName;
029
030    private static int hashCode(final Object[] array) {
031        final int prime = 31;
032        if (array == null) {
033            return 0;
034        }
035        int result = 1;
036        for (final Object element : array) {
037            result = prime * result + (element == null ? 0 : element.hashCode());
038        }
039        return result;
040    }
041
042    public static void setAttributeName(final CPUTF8 cpUTF8Value) {
043        attributeName = cpUTF8Value;
044    }
045
046    private transient int[] exceptionIndexes;
047
048    private final CPClass[] exceptions;
049
050    public ExceptionsAttribute(final CPClass[] exceptions) {
051        super(attributeName);
052        this.exceptions = exceptions;
053    }
054
055    @Override
056    public boolean equals(final Object obj) {
057        if (this == obj) {
058            return true;
059        }
060        if (!super.equals(obj)) {
061            return false;
062        }
063        if (getClass() != obj.getClass()) {
064            return false;
065        }
066        final ExceptionsAttribute other = (ExceptionsAttribute) obj;
067        if (!Arrays.equals(exceptions, other.exceptions)) {
068            return false;
069        }
070        return true;
071    }
072
073    @Override
074    protected int getLength() {
075        return 2 + 2 * exceptions.length;
076    }
077
078    @Override
079    protected ClassFileEntry[] getNestedClassFileEntries() {
080        final ClassFileEntry[] result = new ClassFileEntry[exceptions.length + 1];
081        System.arraycopy(exceptions, 0, result, 0, exceptions.length);
082        result[exceptions.length] = getAttributeName();
083        return result;
084    }
085
086    @Override
087    public int hashCode() {
088        final int prime = 31;
089        int result = super.hashCode();
090        result = prime * result + ExceptionsAttribute.hashCode(exceptions);
091        return result;
092    }
093
094    @Override
095    protected void resolve(final ClassConstantPool pool) {
096        super.resolve(pool);
097        exceptionIndexes = new int[exceptions.length];
098        for (int i = 0; i < exceptions.length; i++) {
099            exceptions[i].resolve(pool);
100            exceptionIndexes[i] = pool.indexOf(exceptions[i]);
101        }
102    }
103
104    @Override
105    public String toString() {
106        final StringBuilder sb = new StringBuilder();
107        sb.append("Exceptions: ");
108        for (final CPClass exception : exceptions) {
109            sb.append(exception);
110            sb.append(' ');
111        }
112        return sb.toString();
113    }
114
115    @Override
116    protected void writeBody(final DataOutputStream dos) throws IOException {
117        dos.writeShort(exceptionIndexes.length);
118        for (final int element : exceptionIndexes) {
119            dos.writeShort(element);
120        }
121    }
122
123}