SQL> select sys_guid() from dual;

 SYS_GUID()

 --------------------------------

 74CC7FA2ABF7437D9AC29798ACC3E129

 SQL> 

 import java.util.UUID;

 import org.junit.Test;

 public class getUUID {

     @Test

     public void getUuid(){

         UUID u = UUID.randomUUID();

         System.out.println(u.toString().replace("-", ""));

     }

 }