java
SCRU128: Sortable, Clock and Random number-based Unique identifier
SCRU128 ID is yet another attempt to supersede UUID for the users who need decentralized, globally unique time-ordered identifiers. SCRU128 is inspired by ULID and KSUID and has the following features:
- 128-bit unsigned integer type
- Sortable by generation time (as integer and as text)
- 25-digit case-insensitive textual representation (Base36)
- 48-bit millisecond Unix timestamp that ensures useful life until year 10889
- Up to 281 trillion time-ordered but unpredictable unique IDs per millisecond
- 80-bit three-layer randomness for global uniqueness
Kotlin examples:
import io.github.scru128.Scru128
// generate a new identifier object
val x = Scru128.generate()
println(x) // e.g., "036z951mhjikzik2gsl81gr7l"
println(x.toByteArray()) // as a 128-bit unsigned integer in big-endian byte array
// generate a textual representation directly
println(Scru128.generateString()) // e.g., "036z951mhzx67t63mq9xe6q0j"
Java examples:
import io.github.scru128.*;
// generate a new identifier object
Scru128Id x = Scru128.generate();
System.out.println(x); // e.g., "036z951mhjikzik2gsl81gr7l"
System.out.println(x.toByteArray()); // as a 128-bit unsigned integer in big-endian byte array
// generate a textual representation directly
System.out.println(Scru128.generateString()); // e.g., "036z951mhzx67t63mq9xe6q0j"
See SCRU128 Specification for details.
Installation
Obtain a copy from Maven Central Repository. build.gradle.kts example:
repositories {
mavenCentral()
}
dependencies {
implementation("io.github.scru128:scru128:<version>")
}
Target environment
- Java 8 or higher
- Android API level 21 (Android 5.0) or higher
License
Licensed under the Apache License, Version 2.0.