How To Create UUID in Java?

In this article you will see, how to create UUID in Java.

Introduction

UUID, a universally unique identifier is a 128-bit number used to identify information in computer systems.

UUID is made of hex digits along with 4 hyphen (“-“) symbols. The length of a UUID is 36 characters.

There are 5 types of UUID but mostly version 4 i.e. Randomly Generated UUID is used.

We are going to create the version 4 UUID here.

Example UUID

df6fdea1-10c3-474c-ae62-e63def80de0b

How to create UUID in Java?

Creating a Randomly Generated UUID (version 4) is really easy in Java.

UUID Class is present in java.util package. And it has the static method randomUUID() which returns the randomly generated UUID.

The example is given below.

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import java.util.UUID;

/**
 * A Java program to create a Randomly Generated UUID i.e. Version 4 UUID
 * @author Gaurav Kukade at coderolls.com
 *
 */
public class CreateUUID {

	public static void main(String[] args) {
		
		// creating random uuid i.e. version 4 UUID
		UUID uuid = UUID.randomUUID();
		
		System.out.println("Printing the randomly generated UUID value......\n");
		
		System.out.println("uuid: "+uuid);
		
	}

}

Output

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Printing the randomly generated UUID value......

uuid: e3aed661-ccc2-42fd-ad69-734fee350cd2

Conclusion

You can create a UUID using the static method randomUUID() of the UUID class.

Get the above code as GitHub Gist.

You can visit my YouTube channel ‘coderolls’ to find more video tutorials.