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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
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 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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/* @test
 * @bug 4173528 5068772 8148936 8196334 8308803
 * @summary Unit tests for java.util.UUID
 * @key randomness
 * @library /test/lib
 * @build jdk.test.lib.RandomFactory
 * @run main/othervm -Xmx1g -XX:+CompactStrings UUIDTest
 * @run main/othervm -Xmx1g -XX:-CompactStrings UUIDTest
 */

import java.util.*;
import java.util.stream.IntStream;
import jdk.test.lib.RandomFactory;

public class UUIDTest {

    // Single UUID instance is ~32 bytes, 1M instances take ~256M in the set
    private static final int COUNT = 1_000_000;

    static final Random generator = RandomFactory.getRandom();

    public static void main(String[] args) throws Exception {
        negativeTest();
        randomUUIDTest();
        randomUUIDTest_Multi();
        nameUUIDFromBytesTest();
        stringTest();
        versionTest();
        variantTest();
        timestampTest();
        clockSequenceTest();
        nodeTest();
        hashCodeEqualsTest();
        compareTo();
    }

    private static void negativeTest() throws Exception {
        Set<UUID> set = new HashSet<>();
        set.add(new UUID(4, 4));
        if (set.add(new UUID(4, 4))) {
            throw new Exception("Contains test does not work as expected");
        }
    }

    private static void randomUUIDTest() throws Exception {
        List<UUID> collisions = new ArrayList<>();

        Set<UUID> set = new HashSet<>();
        for (int i = 0; i < COUNT; i++) {
            UUID u = UUID.randomUUID();
            if (u.version() != 4) {
                throw new Exception("Bad version: " + u);
            }
            if (u.variant() != 2) {
                throw new Exception("Bad variant: " + u);
            }
            if (!set.add(u)) {
                collisions.add(u);
            }
        }

        if (!collisions.isEmpty()) {
           // This is extremely unlikely to happen. If you see this failure,
           // this highly likely points to the implementation bug, rather than
           // the odd chance.
           throw new Exception("UUID collisions detected: " + collisions);
        }
    }

    private static void randomUUIDTest_Multi() throws Exception {
        List<UUID> uuids = IntStream.range(0, COUNT).parallel()
                                    .mapToObj(i -> UUID.randomUUID())
                                    .toList();

        List<UUID> collisions = new ArrayList<>();

        Set<UUID> set = new HashSet<>();
        for (UUID u : uuids) {
            if (u.version() != 4) {
                throw new Exception("Bad version: " + u);
            }
            if (u.variant() != 2) {
                throw new Exception("Bad variant: " + u);
            }
            if (!set.add(u)) {
                collisions.add(u);
            }
        }

        if (!collisions.isEmpty()) {
           // This is extremely unlikely to happen. If you see this failure,
           // this highly likely points to the implementation bug, rather than
           // the odd chance.
           throw new Exception("UUID collisions detected: " + collisions);
        }
    }


    private static void nameUUIDFromBytesTest() throws Exception {
        List<UUID> collisions = new ArrayList<>();

        byte[] someBytes = new byte[12];
        Set<UUID> set = new HashSet<>();
        for (int i = 0; i < COUNT; i++) {
            generator.nextBytes(someBytes);
            UUID u = UUID.nameUUIDFromBytes(someBytes);
            if (u.version() != 3) {
                throw new Exception("Bad version: " + u);
            }
            if (u.variant() != 2) {
                throw new Exception("Bad variant: " + u);
            }
            if (!set.add(u)) {
                collisions.add(u);
            }
        }

        if (!collisions.isEmpty()) {
           // This is extremely unlikely to happen. If you see this failure,
           // this highly likely points to the implementation bug, rather than
           // the odd chance.
           throw new Exception("UUID collisions detected: " + collisions);
        }
    }

    private static void stringTest() throws Exception {
        for (int i = 0; i < COUNT; i++) {
            UUID u1 = UUID.randomUUID();
            UUID u2 = UUID.fromString(u1.toString().toLowerCase());
            UUID u3 = UUID.fromString(u1.toString().toUpperCase());
            if (!u1.equals(u2) || !u1.equals(u3)) {
                throw new Exception("UUID -> string -> UUID failed: " + u1 + " -> " + u2 + " -> " + u3);
            }
        }

        testFromStringError("-0");
        testFromStringError("x");
        testFromStringError("----");
        testFromStringError("-0-0-0-0");
        testFromStringError("0-0-0-0-");
        testFromStringError("0-0-0-0-0-");
        testFromStringError("0-0-0-0-x");
    }

    private static void testFromStringError(String str) {
        try {
            UUID test = UUID.fromString(str);
            throw new RuntimeException("Should have thrown IAE");
        } catch (IllegalArgumentException iae) {
            // pass
        }
    }

    private static void versionTest() throws Exception {
        UUID test = UUID.randomUUID();
        if (test.version() != 4) {
            throw new Exception("randomUUID not type 4: " + test);
        }

        byte[] someBytes = new byte[12];
        generator.nextBytes(someBytes);
        test = UUID.nameUUIDFromBytes(someBytes);
        if (test.version() != 3) {
            throw new Exception("nameUUIDFromBytes not type 3: " + test);
        }

        test = UUID.fromString("9835451d-e2e0-1e41-8a5a-be785f17dcda");
        if (test.version() != 1) {
            throw new Exception("wrong version fromString 1");
        }

        test = UUID.fromString("9835451d-e2e0-2e41-8a5a-be785f17dcda");
        if (test.version() != 2) {
            throw new Exception("wrong version fromString 2");
        }

        test = UUID.fromString("9835451d-e2e0-3e41-8a5a-be785f17dcda");
        if (test.version() != 3) {
            throw new Exception("wrong version fromString 3");
        }

        test = UUID.fromString("9835451d-e2e0-4e41-8a5a-be785f17dcda");
        if (test.version() != 4) {
            throw new Exception("wrong version fromString 4");
        }

        test = new UUID(0x0000000000001000L, 55L);
        if (test.version() != 1) {
            throw new Exception("wrong version from bit set to 1");
        }

        test = new UUID(0x0000000000002000L, 55L);
        if (test.version() != 2) {
            throw new Exception("wrong version from bit set to 2");
        }

        test = new UUID(0x0000000000003000L, 55L);
        if (test.version() != 3) {
            throw new Exception("wrong version from bit set to 3");
        }

        test = new UUID(0x0000000000004000L, 55L);
        if (test.version() != 4) {
            throw new Exception("wrong version from bit set to 4");
        }
    }

    private static void variantTest() throws Exception {
        UUID test = UUID.randomUUID();
        if (test.variant() != 2) {
            throw new Exception("randomUUID not variant 2");
        }

        byte[] someBytes = new byte[12];
        generator.nextBytes(someBytes);
        test = UUID.nameUUIDFromBytes(someBytes);
        if (test.variant() != 2) {
            throw new Exception("nameUUIDFromBytes not variant 2");
        }

        test = new UUID(55L, 0x0000000000001000L);
        if (test.variant() != 0) {
            throw new Exception("wrong variant from bit set to 0");
        }

        test = new UUID(55L, 0x8000000000001000L);
        if (test.variant() != 2) {
            throw new Exception("wrong variant from bit set to 2");
        }

        test = new UUID(55L, 0xc000000000001000L);
        if (test.variant() != 6) {
            throw new Exception("wrong variant from bit set to 6");
        }

        test = new UUID(55L, 0xe000000000001000L);
        if (test.variant() != 7) {
            throw new Exception("wrong variant from bit set to 7");
        }
    }

    private static void timestampTest() throws Exception {
        UUID test = UUID.randomUUID();
        try {
            test.timestamp();
            throw new Exception("Expected exception not thrown");
        } catch (UnsupportedOperationException uoe) {
            // Correct result
        }

        test = UUID.fromString("00000001-0000-1000-8a5a-be785f17dcda");
        if (test.timestamp() != 1) {
            throw new Exception("Incorrect timestamp");
        }

        test = UUID.fromString("00000400-0000-1000-8a5a-be785f17dcda");
        if (test.timestamp() != 1024) {
            throw new Exception("Incorrect timestamp");
        }

        test = UUID.fromString("FFFFFFFF-FFFF-1FFF-8a5a-be785f17dcda");
        if (test.timestamp() != (Long.MAX_VALUE >> 3)) {
            throw new Exception("Incorrect timestamp");
        }
    }

    private static void clockSequenceTest() throws Exception {
        UUID test = UUID.randomUUID();
        try {
            test.clockSequence();
            throw new Exception("Expected exception not thrown");
        } catch (UnsupportedOperationException uoe) {
            // Correct result
        }

        test = UUID.fromString("00000001-0000-1000-8001-be785f17dcda");
        if (test.clockSequence() != 1) {
            throw new Exception("Incorrect sequence");
        }

        test = UUID.fromString("00000001-0000-1000-8002-be785f17dcda");
        if (test.clockSequence() != 2) {
            throw new Exception("Incorrect sequence");
        }

        test = UUID.fromString("00000001-0000-1000-8010-be785f17dcda");
        if (test.clockSequence() != 16) {
            throw new Exception("Incorrect sequence");
        }

        test = UUID.fromString("00000001-0000-1000-bFFF-be785f17dcda");
        if (test.clockSequence() != ((1L << 14) - 1)) {
            throw new Exception("Incorrect sequence");
        }
    }

    private static void nodeTest() throws Exception {
        UUID test = UUID.randomUUID();
        try {
            test.node();
            throw new Exception("Expected exception not thrown");
        } catch (UnsupportedOperationException uoe) {
            // Correct result
        }

        test = UUID.fromString("00000001-0000-1000-8001-000000000001");
        if (test.node() != 1) {
            throw new Exception("Incorrect node");
        }

        test = UUID.fromString("00000001-0000-1000-8002-FFFFFFFFFFFF");
        if (test.node() != ((1L << 48) - 1)) {
            throw new Exception("Incorrect node");
        }
    }

    private static void hashCodeEqualsTest() throws Exception {
        // If two UUIDs are equal they must have the same hashCode
        for (int i = 0; i < COUNT; i++) {
            UUID u1 = UUID.randomUUID();
            UUID u2 = UUID.fromString(u1.toString());
            if (u1.hashCode() != u2.hashCode()) {
                throw new Exception("Equal UUIDs with different hash codes: " + u1 + "(" + u1.hashCode() + ") " +
                                    "and " + u2 + "(" + u2.hashCode() + ")");
            }
        }

        // Test equality of UUIDs with tampered bits
        for (int i = 0; i < COUNT; i++) {
            long l = generator.nextLong();
            long l2 = generator.nextLong();
            int position = generator.nextInt(64);
            UUID u1 = new UUID(l, l2);
            l = l ^ (1L << position);
            UUID u2 = new UUID(l, l2);
            if (u1.equals(u2)) {
                throw new Exception("UUIDs with different bits equal: " + u1 + " and " + u2);
            }
        }
    }

    private static void compareTo() throws Exception {
        UUID id = new UUID(33L, 63L);
        UUID id2 = new UUID(34L, 62L);
        UUID id3 = new UUID(34L, 63L);
        UUID id4 = new UUID(34L, 64L);
        UUID id5 = new UUID(35L, 63L);

        if ((id.compareTo(id2) >= 0) ||
            (id2.compareTo(id3) >= 0) ||
            (id3.compareTo(id4) >= 0) ||
            (id4.compareTo(id5) >= 0)) {
            throw new RuntimeException("compareTo failure");
        }

        if ((id5.compareTo(id4) <= 0) ||
            (id4.compareTo(id3) <= 0) ||
            (id3.compareTo(id2) <= 0) ||
            (id2.compareTo(id) <= 0)) {
            throw new RuntimeException("compareTo failure");
        }

        if (id.compareTo(id) != 0) {
            throw new RuntimeException("compareTo failure");
        }
    }

}