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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 *  Unless required by applicable law or agreed to in writing, software

 *  distributed under the License is distributed on an "AS IS" BASIS,

 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 *  See the License for the specific language governing permissions and

 *  limitations under the License.

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package com.sun.org.apache.bcel.internal.classfile;

import java.io.DataInput;

import java.io.DataOutputStream;

import java.io.IOException;

import com.sun.org.apache.bcel.internal.Const;

/**

 * This class is derived from <em>Attribute</em> and records the classes and interfaces that

 * are authorized to claim membership in the nest hosted by the current class or interface.

 * There may be at most one NestMembers attribute in a ClassFile structure.

 *

 * @see     Attribute

 */

public final class NestMembers extends Attribute {

    private int[] classes;

    /**

     * Initialize from another object. Note that both objects use the same

     * references (shallow copy). Use copy() for a physical copy.

     */

    public NestMembers(final NestMembers c) {

        this(c.getNameIndex(), c.getLength(), c.getClasses(), c.getConstantPool());

    }

    /**

     * @param name_index Index in constant pool

     * @param length Content length in bytes

     * @param classes Table of indices in constant pool

     * @param constant_pool Array of constants

     */

    public NestMembers(final int name_index, final int length, final int[] classes,

            final ConstantPool constant_pool) {

        super(Const.ATTR_NEST_MEMBERS, name_index, length, constant_pool);

        this.classes = classes != null ? classes : new int[0];

    }

    /**

     * Construct object from input stream.

     * @param name_index Index in constant pool

     * @param length Content length in bytes

     * @param input Input stream

     * @param constant_pool Array of constants

     * @throws IOException

     */

    NestMembers(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool) throws IOException {

        this(name_index, length, (int[]) null, constant_pool);

        final int number_of_classes = input.readUnsignedShort();

        classes = new int[number_of_classes];

        for (int i = 0; i < number_of_classes; i++) {

            classes[i] = input.readUnsignedShort();

        }

    }

    /**

     * Called by objects that are traversing the nodes of the tree implicitely

     * defined by the contents of a Java class. I.e., the hierarchy of methods,

     * fields, attributes, etc. spawns a tree of objects.

     *

     * @param v Visitor object

     */

    @Override

    public void accept( final Visitor v ) {

        v.visitNestMembers(this);

    }

    /**

     * Dump NestMembers attribute to file stream in binary format.

     *

     * @param file Output file stream

     * @throws IOException

     */

    @Override

    public void dump( final DataOutputStream file ) throws IOException {

        super.dump(file);

        file.writeShort(classes.length);

        for (final int index : classes) {

            file.writeShort(index);

        }

    }

    /**

     * @return array of indices into constant pool of class names.

     */

    public int[] getClasses() {

        return classes;

    }

    /**

     * @return Length of classes table.

     */

    public int getNumberClasses() {

        return classes == null ? 0 : classes.length;

    }

    /**

     * @return string array of class names

     */

    public String[] getClassNames() {

        final String[] names = new String[classes.length];

        for (int i = 0; i < classes.length; i++) {

            names[i] = super.getConstantPool().getConstantString(classes[i],

                    Const.CONSTANT_Class).replace('/', '.');

        }

        return names;

    }

    /**

     * @param classes the list of class indexes

     * Also redefines number_of_classes according to table length.

     */

    public void setClasses( final int[] classes ) {

        this.classes = classes != null ? classes : new int[0];

    }

    /**

     * @return String representation, i.e., a list of classes.

     */

    @Override

    public String toString() {

        final StringBuilder buf = new StringBuilder();

        buf.append("NestMembers(");

        buf.append(classes.length);

        buf.append("):\n");

        for (final int index : classes) {

            final String class_name = super.getConstantPool().getConstantString(index, Const.CONSTANT_Class);

            buf.append("  ").append(Utility.compactClassName(class_name, false)).append("\n");

        }

        return buf.substring(0, buf.length()-1); // remove the last newline

    }

    /**

     * @return deep copy of this attribute

     */

    @Override

    public Attribute copy( final ConstantPool _constant_pool ) {

        final NestMembers c = (NestMembers) clone();

        if (classes != null) {

            c.classes = new int[classes.length];

            System.arraycopy(classes, 0, c.classes, 0,

                    classes.length);

        }

        c.setConstantPool(_constant_pool);

        return c;

    }

}