UUID Generator

implementation 'io.github.honhimw:uuid-java:{latest}'

---

Benchmark

./gradlew bench

Details

JMH version: 1.37
VM version: JDK 25.0.1, Java HotSpot (TM) 64-Bit Server VM, 25.0.1+8-LTS-jvmci-b01
Warmup: 5 iterations, 5 s each Measurement: 4 iterations, 4 s each Threads: 6 threads, will synchronize iterations
Benchmark mode: Throughput, ops/time

Name	Score(thrpt)
V1Fasterxml	9875.550 ops/ms
V1Self	251569.564 ops/ms
V1UuidCreator	33725.897 ops/ms
V3Fasterxml	6505.923 ops/ms
V3Self	50167.978 ops/ms
V3UuidCreator	37720.554 ops/ms
V4Fasterxml	2807239.341 ops/ms
V4Jdk	1012.926 ops/ms
V4Self	2801417.654 ops/ms
V4UuidCreator	42465.890 ops/ms
V5Fasterxml	3285.011 ops/ms
V5Self	23947.733 ops/ms
V5UuidCreator	19930.041 ops/ms
V6Fasterxml	9875.309 ops/ms
V6Self	273115.546 ops/ms
V6UuidCreator	35289.157 ops/ms
V7Fastest	1373584.697 ops/ms
V7Self	1268108.792 ops/ms

---

Usage

import io.github.honhimw.uuid.*;
import io.github.honhimw.uuid.gen.*;

void main() {
    // Using via global shared instances.
    Generator generator = UUIDs
        .FAST  // FAST | SECURE default configuration
        .V7; // V1 | V3 | V4 | V5 | V6 | V7
    UUID uuid = generator.next(); // Generation
//    UUID uuid = UUIDs.FAST.V1.now(MacAddress.nodeId());
//    UUID uuid = UUIDs.FAST.V3.of("foo");
//    UUID uuid = UUIDs.FAST.V4.next();
//    UUID uuid = UUIDs.FAST.V5.of("bar");
//    UUID uuid = UUIDs.FAST.V6.now(MacAddress.nodeId());
//    UUID uuid = UUIDs.FAST.V7.of(CounterSequence.SHARED.timestamp());
}

Customize

void main() {
    V7 v7 = new V7(Context.builder()
        .clock(
            new V7.ClockSequenceV7()   // Reseeding timestamp context
                .withAdditionalPrecision() // Add 12-bits for timestamp-precision
        )
        .random(() -> ThreadLocalRandom.current()) // For fast. `new SecureRandom()` for secure
        .node(() -> MacAddress.nodeId()) // Using other by specificizing NodeId.of(new byte[] {1, 2, 3, 4, 5, 6})
        .messageDigest(algorithm -> MessageDigest.getInstance(algorithm)) // MessageDigest provider(getting from thread-local cache?)
        .build());
    v7.next(); // Generation
}

Typed Uuid

import io.github.honhimw.uuid.Uuid;

void main() {
    UUID jdkUUID = UUID.randomUUID();
    Uuid uuid = Uuid.fromUUID(jdkUUID);

    assert Variant.RFC4122 == uuid.variant() : "variant RFC4122";
    assert Version.RANDOM == uuid.version() : "version 4";
    assert uuid.timestamp().isEmpty() : "not time based";
    assert uuid.node().isEmpty() : "no node";

    jdkUUID = uuid.asUUID();
    byte[] bytes = uuid.asBytes();
}