NOTE: The external version number of this release is 5.0 and its internal version number is 1.5.0, as described at J2SE Naming and Versioning.
Java technology was introduced 9 years ago and it's been over 5 years since the introduction of J2SE, the 2nd generation Java platform.
Given its rich history, changing the version of the next release from 1.5 to 5.0 better reflects the level of maturity, stability, scalability and security built into J2SE. Here are the official naming and versioning conventions for the upcoming release (also known as "Tiger"):