Java.util.UUID Class
Java UUID Class
Java.util package provides an UUID class which represents an immutable universally unique identifier (UUID). A UUID represents a 128-bit value. It is used for creating random file names, session id in web application, transaction id etc. There are four different basic types of UUIDs: time-based, DCE security, name-based, and randomly generated UUIDs.
Class declaration
The declaration of java.util.UUID class is:
public final class UUID
extends Object
implements Serializable, Comparable<UUID>
Here, E is the type of element maintained by the container.
Class Constructor
| S.N | Constructors & Description |
|---|---|
| 1. |
UUID(long mostSigBits, long leastSigBits) Constructs a new UUID using the specified data. |
java.util.UUID Methods
The java.util.UUID class has a number of methods which are listed below:
Member Methods
| S.N | Methods & Description |
|---|---|
| 1. |
int clockSequence() Returns the clock sequence value associated with this UUID. |
| 2. |
int compareTo(UUID val) Compares this UUID with the specified UUID. |
| 3. |
boolean equals(Object obj) Compares this object to the specified object. |
| 4. |
static UUID fromString(String name) Creates a UUID from the string standard representation. |
| 5. |
long getLeastSignificantBits() Returns the least significant 64 bits of this UUID's 128 bit value. |
| 6. |
long getMostSignificantBits() Returns the most significant 64 bits of this UUID's 128 bit value. |
| 7. |
int hashCode() Returns a hash code for this UUID. |
| 8. |
static UUID nameUUIDFromBytes(byte[] name) Static factory to retrieve a type 3 (name based) UUID based on the specified byte array. |
| 9. |
long node() Returns the node value associated with this UUID. |
| 10. |
static UUID randomUUID() Static factory to retrieve a type 4 (pseudo randomly generated) UUID. |
| 11. |
long timestamp() Returns the timestamp value associated with this UUID. |
| 12. |
String toString() Returns a String object representing this UUID. |
| 13. |
int variant() Returns the variant number associated with this UUID. |
| 14. |
int version() Returns the version number associated with this UUID. |
Methods inherited
This class inherits the methods of following class:
- java.lang.Object
