/*

 * Copyright (c) 2005, 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.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * @test

 * @bug     5018254

 * @summary Test null-allowing Comparators

 * @author  Martin Buchholz

 */

import java.util.*;

import java.util.concurrent.*;

public class NullAtEnd {

    static volatile int passed = 0, failed = 0;

    static void fail(String msg) {

        failed++;

        new AssertionError(msg).printStackTrace();

    }

    static void pass() {

        passed++;

    }

    static void unexpected(Throwable t) {

        failed++;

        t.printStackTrace();

    }

    static void check(boolean condition, String msg) {

        if (condition)

            passed++;

        else

            fail(msg);

    }

    static void check(boolean condition) {

        check(condition, "Assertion failure");

    }

    private static boolean eq(Object x, Object y) {

        return x == null ? y == null : x.equals(y);

    }

    private static final Comparator<String> NULL_AT_END

        = new Comparator<String>() {

            /**

             * Allows for nulls.  Null is greater than anything non-null.

             */

            public int compare(String x, String y) {

                if (x == null && y == null) return 0;

                if (x == null && y != null) return 1;

                if (x != null && y == null) return -1;

                return x.compareTo(y);

            }

        };

    public static void main(String[] args) {

        try {

            SortedMap<String,String> m1

                = new TreeMap<String,String>(NULL_AT_END);

            check(eq(m1.put("a", "a"), null));

            check(eq(m1.put("b", "b"), null));

            check(eq(m1.put("c", "c"), null));

            check(eq(m1.put(null, "d"), null));

            SortedMap<String,String> m2 = new TreeMap<String,String>(m1);

            check(eq(m1.lastKey(), null));

            check(eq(m1.get(m1.lastKey()), "d"));

            check(eq(m1.remove(m1.lastKey()), "d"));

            check(eq(m1.lastKey(), "c"));

            check(eq(m2.entrySet().toString(), "[a=a, b=b, c=c, null=d]"));

            SortedMap<String,String> m3 = m2.tailMap("b");

            check(eq(m3.lastKey(), null));

            check(eq(m3.get(m3.lastKey()), "d"));

            check(eq(m3.remove(m3.lastKey()), "d"));

            check(eq(m3.lastKey(), "c"));

        } catch (Throwable t) { unexpected(t); }

        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);

        if (failed > 0) throw new Error("Some tests failed");

    }

}