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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 represents an entry in the opens table of the Module attribute.

 * Each entry describes a package which the parent module opens.

 *

 * @see   Module

 * @since 6.4.0

 */

public final class ModuleOpens implements Cloneable, Node {

    private final int opensIndex;  // points to CONSTANT_Package_info

    private final int opensFlags;

    private final int opensToCount;

    private final int[] opensToIndex;  // points to CONSTANT_Module_info

    /**

     * Construct object from file stream.

     *

     * @param file Input stream

     * @throws IOException if an I/O Exception occurs in readUnsignedShort

     */

    ModuleOpens(final DataInput file) throws IOException {

        opensIndex = file.readUnsignedShort();

        opensFlags = file.readUnsignedShort();

        opensToCount = file.readUnsignedShort();

        opensToIndex = new int[opensToCount];

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

            opensToIndex[i] = file.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.visitModuleOpens(this);

    }

    // TODO add more getters and setters?

    /**

     * Dump table entry to file stream in binary format.

     *

     * @param file Output file stream

     * @throws IOException if an I/O Exception occurs in writeShort

     */

    public void dump( final DataOutputStream file ) throws IOException {

        file.writeShort(opensIndex);

        file.writeShort(opensFlags);

        file.writeShort(opensToCount);

        for (final int entry : opensToIndex) {

            file.writeShort(entry);

        }

    }

    /**

     * @return String representation

     */

    @Override

    public String toString() {

        return "opens(" + opensIndex + ", " + opensFlags + ", " + opensToCount + ", ...)";

    }

    /**

     * @return Resolved string representation

     */

    public String toString( final ConstantPool constant_pool ) {

        final StringBuilder buf = new StringBuilder();

        final String package_name = constant_pool.constantToString(opensIndex, Const.CONSTANT_Package);

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

        buf.append(", ").append(String.format("%04x", opensFlags));

        buf.append(", to(").append(opensToCount).append("):\n");

        for (final int index : opensToIndex) {

            final String module_name = constant_pool.getConstantString(index, Const.CONSTANT_Module);

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

        }

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

    }

    /**

     * @return deep copy of this object

     */

    public ModuleOpens copy() {

        try {

            return (ModuleOpens) clone();

        } catch (final CloneNotSupportedException e) {

            // TODO should this throw?

        }

        return null;

    }

}