/*

 * Copyright (c) 2000, 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 4245809

 * @summary Basic test for LinkedHashSet.  (Based on SetBash)

 */

import java.io.ByteArrayInputStream;

import java.io.ByteArrayOutputStream;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.util.Arrays;

import java.util.Iterator;

import java.util.LinkedHashSet;

import java.util.Random;

import java.util.Set;

public class Basic {

    static Random rnd = new Random(666);

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

        int numItr =  500;

        int setSize = 500;

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

            Set s1 = new LinkedHashSet();

            AddRandoms(s1, setSize);

            Set s2 = new LinkedHashSet();

            AddRandoms(s2, setSize);

            Set intersection = clone(s1);

            intersection.retainAll(s2);

            Set diff1 = clone(s1); diff1.removeAll(s2);

            Set diff2 = clone(s2); diff2.removeAll(s1);

            Set union = clone(s1); union.addAll(s2);

            if (diff1.removeAll(diff2))

                throw new Exception("Set algebra identity 2 failed");

            if (diff1.removeAll(intersection))

                throw new Exception("Set algebra identity 3 failed");

            if (diff2.removeAll(diff1))

                throw new Exception("Set algebra identity 4 failed");

            if (diff2.removeAll(intersection))

                throw new Exception("Set algebra identity 5 failed");

            if (intersection.removeAll(diff1))

                throw new Exception("Set algebra identity 6 failed");

            if (intersection.removeAll(diff1))

                throw new Exception("Set algebra identity 7 failed");

            intersection.addAll(diff1); intersection.addAll(diff2);

            if (!intersection.equals(union))

                throw new Exception("Set algebra identity 1 failed");

            if (new LinkedHashSet(union).hashCode() != union.hashCode())

                throw new Exception("Incorrect hashCode computation.");

            Iterator e = union.iterator();

            while (e.hasNext())

                if (!intersection.remove(e.next()))

                    throw new Exception("Couldn't remove element from copy.");

            if (!intersection.isEmpty())

                throw new Exception("Copy nonempty after deleting all elements.");

            e = union.iterator();

            while (e.hasNext()) {

                Object o = e.next();

                if (!union.contains(o))

                    throw new Exception("Set doesn't contain one of its elements.");

                e.remove();

                if (union.contains(o))

                    throw new Exception("Set contains element after deletion.");

            }

            if (!union.isEmpty())

                throw new Exception("Set nonempty after deleting all elements.");

            s1.clear();

            if (!s1.isEmpty())

                throw new Exception("Set nonempty after clear.");

        }

        System.err.println("Success.");

    }

    static Set clone(Set s) throws Exception {

        Set clone;

        int method = rnd.nextInt(3);

        clone = (method==0 ? (Set) ((LinkedHashSet)s).clone() :

                 (method==1 ? new LinkedHashSet(Arrays.asList(s.toArray())) :

                  serClone(s)));

        if (!s.equals(clone))

            throw new Exception("Set not equal to copy: "+method);

        if (!s.containsAll(clone))

            throw new Exception("Set does not contain copy.");

        if (!clone.containsAll(s))

            throw new Exception("Copy does not contain set.");

        return clone;

    }

    private static Set serClone(Set m) {

        Set result = null;

        try {

            // Serialize

            ByteArrayOutputStream bos = new ByteArrayOutputStream();

            ObjectOutputStream out = new ObjectOutputStream(bos);

            out.writeObject(m);

            out.flush();

            // Deserialize

            ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());

            out.close();

            ObjectInputStream in = new ObjectInputStream(bis);

            result = (Set)in.readObject();

            in.close();

        } catch (Exception e) {

            e.printStackTrace();

        }

        return result;

    }

    static void AddRandoms(Set s, int n) throws Exception {

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

            Integer e = rnd.nextInt(n);

            int preSize = s.size();

            boolean prePresent = s.contains(e);

            boolean added = s.add(e);

            if (!s.contains(e))

                throw new Exception("Element not present after addition.");

            if (added == prePresent)

                throw new Exception("added == alreadyPresent");

            int postSize = s.size();

            if (added && preSize == postSize)

                throw new Exception("Add returned true, but size didn't change.");

            if (!added && preSize != postSize)

                throw new Exception("Add returned false, but size changed.");

        }

    }

}