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 *
017 */
018package org.apache.bcel.classfile;
019
020import java.io.DataInput;
021import java.io.DataOutputStream;
022import java.io.IOException;
023
024import org.apache.bcel.Const;
025
026/**
027 * This class is derived from <em>Attribute</em> and denotes that this class
028 * is an Inner class of another.
029 * to the source file of this class.
030 * It is instantiated from the <em>Attribute.readAttribute()</em> method.
031 *
032 * @version $Id: InnerClasses.java 1749603 2016-06-21 20:50:19Z ggregory $
033 * @see     Attribute
034 */
035public final class InnerClasses extends Attribute {
036
037    private InnerClass[] inner_classes;
038
039
040    /**
041     * Initialize from another object. Note that both objects use the same
042     * references (shallow copy). Use clone() for a physical copy.
043     */
044    public InnerClasses(final InnerClasses c) {
045        this(c.getNameIndex(), c.getLength(), c.getInnerClasses(), c.getConstantPool());
046    }
047
048
049    /**
050     * @param name_index Index in constant pool to CONSTANT_Utf8
051     * @param length Content length in bytes
052     * @param inner_classes array of inner classes attributes
053     * @param constant_pool Array of constants
054     */
055    public InnerClasses(final int name_index, final int length, final InnerClass[] inner_classes,
056            final ConstantPool constant_pool) {
057        super(Const.ATTR_INNER_CLASSES, name_index, length, constant_pool);
058        this.inner_classes = inner_classes != null ? inner_classes : new InnerClass[0];
059    }
060
061
062    /**
063     * Construct object from input stream.
064     *
065     * @param name_index Index in constant pool to CONSTANT_Utf8
066     * @param length Content length in bytes
067     * @param input Input stream
068     * @param constant_pool Array of constants
069     * @throws IOException
070     */
071    InnerClasses(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool)
072            throws IOException {
073        this(name_index, length, (InnerClass[]) null, constant_pool);
074        final int number_of_classes = input.readUnsignedShort();
075        inner_classes = new InnerClass[number_of_classes];
076        for (int i = 0; i < number_of_classes; i++) {
077            inner_classes[i] = new InnerClass(input);
078        }
079    }
080
081
082    /**
083     * Called by objects that are traversing the nodes of the tree implicitely
084     * defined by the contents of a Java class. I.e., the hierarchy of methods,
085     * fields, attributes, etc. spawns a tree of objects.
086     *
087     * @param v Visitor object
088     */
089    @Override
090    public void accept( final Visitor v ) {
091        v.visitInnerClasses(this);
092    }
093
094
095    /**
096     * Dump source file attribute to file stream in binary format.
097     *
098     * @param file Output file stream
099     * @throws IOException
100     */
101    @Override
102    public final void dump( final DataOutputStream file ) throws IOException {
103        super.dump(file);
104        file.writeShort(inner_classes.length);
105        for (final InnerClass inner_class : inner_classes) {
106            inner_class.dump(file);
107        }
108    }
109
110
111    /**
112     * @return array of inner class "records"
113     */
114    public final InnerClass[] getInnerClasses() {
115        return inner_classes;
116    }
117
118
119    /**
120     * @param inner_classes the array of inner classes
121     */
122    public final void setInnerClasses( final InnerClass[] inner_classes ) {
123        this.inner_classes = inner_classes != null ? inner_classes : new InnerClass[0];
124    }
125
126
127    /**
128     * @return String representation.
129     */
130    @Override
131    public final String toString() {
132        final StringBuilder buf = new StringBuilder();
133        buf.append("InnerClasses(");
134        buf.append(inner_classes.length);
135        buf.append("):\n");
136        for (final InnerClass inner_class : inner_classes) {
137            buf.append(inner_class.toString(super.getConstantPool())).append("\n");
138        }
139        return buf.toString();
140    }
141
142
143    /**
144     * @return deep copy of this attribute
145     */
146    @Override
147    public Attribute copy( final ConstantPool _constant_pool ) {
148        // TODO this could be recoded to use a lower level constructor after creating a copy of the inner classes
149        final InnerClasses c = (InnerClasses) clone();
150        c.inner_classes = new InnerClass[inner_classes.length];
151        for (int i = 0; i < inner_classes.length; i++) {
152            c.inner_classes[i] = inner_classes[i].copy();
153        }
154        c.setConstantPool(_constant_pool);
155        return c;
156    }
157}