UUID

Generate UUIDs (or GUIDs) in Java

This is an implementation of the UUIDs and GUIDs specification in Java. UUIDs are 128 bit long identifiers that are guaranteed to be unique.

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Documentation

A UUID (or GUID) is a unique identifier that can be created whithout a central authority. UUIDs can be used if a sequence number is not good enough. This implementation is thread safe and very fast.

UUID generates version 1 UUIDs that contain the the MAC address of a network card.

UUID is licensed under the MIT License (OSI certified).

Example code

UUID is very easy to use.

import com.eaio.uuid.UUID;

public class UUIDTest {
 public static void main(String[] args) {
  UUID u = new UUID();
  System.out.println(u);
 }
}

You can assemble UUIDs yourself:

UUID u = new UUID(4242L, 4242L);

Of course, comparing and equality testing is fully implemented:

UUID u1 = new UUID(4242L, 0L);
UUID u2 = new UUID(5203L, 9412);
System.out.println(u1.equals(u2)); // prints out "false"
System.out.println(u1.compareTo(u2)); // prints out "-1"

As well as cloning:

UUID u1 = new UUID(4242L, 0L);
UUID u2 = (UUID) u1.clone();
UUID u3 = new UUID(u1); // or use the clone constructor

And parsing from Strings:

UUID u = new UUID("00000000-0000-002a-0000-00000000002a");
 

Keep in mind that this UUID implementation has public field, so cloning should be used for security purposes between in-VM system boundaries.

Maven

To get UUID through Maven, add the following to your pom.xml:

	<dependencies>
		<dependency>
			<groupId>com.eaio.uuid</groupId>
			<artifactId>uuid</artifactId>
			<version>3.5</version>
		</dependency>
	</dependencies>
…
	<repositories>
		<repository>
			<id>eaio.com</id>
			<url>https://repo.eaio.com/maven2</url>
		</repository>
	</repositories>

Other resources

• Maven-generated Site
• APIdoc