Java 101: Generate a unique identifier with java.util.UUID

A friend of mine was asking me how to generate a unique ID for his application... As you probably already know Java SE 5 has introduced the java.util.UUID class to easily generate Universally Unique Identifier (UUID). As usual Wikipedia is a great starting point to learn more about UUID.
Generating the unique ID is as simple as calling the method UUID.randomUUID() in the class. This will give a new instance of UUID that you can now manipulate; for example do a toString() to get the UUID string representation as describe in the specifications; for example 5462dc18-4653-42d1-b4e4-22fc970a6ce5

Resources:

• UUID on Wikipedia
• java.util.UUID Documentation

OracleAS, OC4J and Java EE releases....

This morning I was helping a customer to debug some Web Services deployment issues, when I simply realized that the error was coming from the fact that he was trying to deploy a JAX-RPC service on a OracleAS 10gR2 server; where it is not supported/available. This give me the opportunity to clarify the different versions of the Oracle Application Server and their related Java Enterprise Edition release support.

Oracle AS Release	J2EE/Java EE Release	Comments/Extensions	Certification Matrix
11.1.0.0	Java EE 5.0	Currently available as technology preview
10.1.3.x (Oracle AS 10gR3)	J2EE 1.4	Support of EJB 3/JPA Web Services Annotations MTOM support (10.1.3.1) Integration of Spring 2.0 (10.1.3.2) Integrationf of Oracle Coherence (10.1.3.3)	OTN Certicification Matrix
10.1.2.x (Oracle AS 10gR2)	J2EE 1.3		OTN Certicification Matrix
9.0.4.x	J2EE 1.3		OTN Certicification Matrix
9.0.3.x	J2EE 1.3		OTN Certicification Matrix