Java UUID clockSequence() Method

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Description

The Java UUID clockSequence() method is used to return the clock sequence value associated with this UUID.

Declaration

Following is the declaration for java.util.UUID.clockSequence() method.

public int clockSequence()

Parameters

NA

Return Value

The method call returns the clock sequence of this UUID.

Exception

UnsupportedOperationException − This exception is thrown if this UUID is not a version 1 UUID.

Checking Clock Sequence associated with UUID generated using Standard Format String Example

The following example shows the usage of Java UUID clockSequence() method to get the clock sequence value associated with this UUID. We've created a UUID object using a given string. Then we've printed the clock sequence value associated with the UUID object using clockSequence() method.

package com.tutorialspoint;

import java.util.UUID;

public class UUIDDemo {
   public static void main(String[] args) {

      // creating UUID      
      UUID x = UUID.fromString("38400000-8cf0-11bd-b23e-10b96e4ef00d");

      // getting clock sequence value
      System.out.println("Clock sequence value: "+x.clockSequence());    
   }    
}

Output

Let us compile and run the above program, this will produce the following result.

Clock sequence value: 12862

Checking Clock Sequence associated with a Random UUID generated Example

The following example shows usage of Java UUID clockSequence() method to get the clock sequence value associated with this UUID which is not supported. We've created a UUID object using randomUUID() method. Then we tried getting the clock sequence value associated with the UUID object using clockSequence() method. It throws exception which we've captured and printed.

package com.tutorialspoint;

import java.util.UUID;

public class UUIDDemo {
   public static void main(String[] args) {

      // creating UUID      
      UUID x = UUID.randomUUID();

      try {
         // getting clock sequence value
         System.out.println("Clock sequence value: "+x.clockSequence());
      } catch(Exception e) {
         e.printStackTrace();
      }
   }    
}

Output

Let us compile and run the above program, this will produce the following result.

java.lang.UnsupportedOperationException: Not a time-based UUID
	at java.base/java.util.UUID.clockSequence(UUID.java:338)
	at com.tutorialspoint.UUIDDemo.main(UUIDDemo.java:13)

Checking Clock Sequence associated with UUID generated using Bytes Example

The following example shows usage of Java UUID clockSequence() method to get the clock sequence value associated with this UUID which is not supported. We've created a UUID object using nameUUIDFromBytes() method. Then we tried getting the clock sequence value associated with the UUID object using clockSequence() method. It throws exception which we've captured and printed.

package com.tutorialspoint;

import java.util.UUID;

public class UUIDDemo {
   public static void main(String[] args) {

      // creating byte array 
      byte[] nbyte = {10,20,30};

      // creating UUID from byte     
      UUID uid = UUID.nameUUIDFromBytes(nbyte);

      try {
         // getting clock sequence value
         System.out.println("Clock sequence value: "+uid.clockSequence());
      } catch(Exception e) {
         e.printStackTrace();
      }
   }    
}

Output

Let us compile and run the above program, this will produce the following result.

java.lang.UnsupportedOperationException: Not a time-based UUID
	at java.base/java.util.UUID.clockSequence(UUID.java:338)
	at com.tutorialspoint.UUIDDemo.main(UUIDDemo.java:16)