/*

 * Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

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 */

/*

 * @test

 * @bug 8015927

 * @summary Class reference duplicates in constant pool

 * @clean ClassRefDupInConstantPoolTest$Duplicates.class

 * @run main ClassRefDupInConstantPoolTest

 */

import java.util.TreeSet;

import com.sun.tools.classfile.*;

import com.sun.tools.classfile.ConstantPool.*;

public class ClassRefDupInConstantPoolTest {

    public static void main(String[] args) throws Exception {

        ClassFile cls = ClassFile.read(ClassRefDupInConstantPoolTest.class.

                                       getResourceAsStream("ClassRefDupInConstantPoolTest$Duplicates.class"));

        ConstantPool pool = cls.constant_pool;

        int duplicates = 0;

        TreeSet<Integer> set = new TreeSet<>();

        for (CPInfo i : pool.entries()) {

            if (i.getTag() == ConstantPool.CONSTANT_Class) {

                CONSTANT_Class_info ci = (CONSTANT_Class_info)i;

                if (!set.add(ci.name_index)) {

                    duplicates++;

                    System.out.println("DUPLICATE CLASS REF " + ci.getName());

                }

            }

        }

        if (duplicates > 0)

            throw new Exception("Test Failed");

    }

    class Duplicates {

        String concat(String s1, String s2) {

            return s1 + (s2 == s1 ? " " : s2);

        }

    }

}