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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 indicates the main class of a module.

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

 *

 * @see     Attribute

 */

public final class ModuleMainClass extends Attribute {

    private int mainClassIndex;

    /**

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

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

     */

    public ModuleMainClass(final ModuleMainClass c) {

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

    }

    /**

     * @param name_index Index in constant pool

     * @param length Content length in bytes

     * @param mainClassIndex Host class index

     * @param constantPool Array of constants

     */

    public ModuleMainClass(final int name_index, final int length, final int mainClassIndex,

            final ConstantPool constantPool) {

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

        this.mainClassIndex = mainClassIndex;

    }

    /**

     * Construct object from input stream.

     * @param nameIndex Index in constant pool

     * @param length Content length in bytes

     * @param input Input stream

     * @param constantPool Array of constants

     * @throws IOException

     */

    ModuleMainClass(final int nameIndex, final int length, final DataInput input, final ConstantPool constantPool) throws IOException {

        this(nameIndex, length, 0, constantPool);

        mainClassIndex = input.readUnsignedShort();

    }

    /**

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

     * 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.visitModuleMainClass(this);

    }

    /**

     * Dump ModuleMainClass attribute to file stream in binary format.

     *

     * @param file Output file stream

     * @throws IOException if an I/O error occurs.

     */

    @Override

    public void dump( final DataOutputStream file ) throws IOException {

        super.dump(file);

        file.writeShort(mainClassIndex);

    }

    /**

     * @return index into constant pool of host class name.

     */

    public int getHostClassIndex() {

        return mainClassIndex;

    }

    /**

     * @param mainClassIndex the host class index

     */

    public void setHostClassIndex( final int mainClassIndex ) {

        this.mainClassIndex = mainClassIndex;

    }

    /**

     * @return String representation

     */

    @Override

    public String toString() {

        final StringBuilder buf = new StringBuilder();

        buf.append("ModuleMainClass: ");

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

        buf.append(Utility.compactClassName(class_name, false));

        return buf.toString();

    }

    /**

     * @return deep copy of this attribute

     */

    @Override

    public Attribute copy( final ConstantPool _constant_pool ) {

        final ModuleMainClass c = (ModuleMainClass) clone();

        c.setConstantPool(_constant_pool);

        return c;

    }

}