• JAR file indexing. If you ask it, jar will examine your jar files and create a text file called INDEX.LIST, which contains a list of all the classes and the jar file where they can be found, which can speed up class loading. This feature has been in Java since… the JDK 1.3!

  • Mercurial, a GPL source-control system, which I wouldn’t care much for if I didn’t just learn that it will probably be used to open source the JDK..

In the blog entry linked above, Mark Reinhold spends a great deal of time discussing source control systems, but he fails to really explain why they picked this odd choice. And just to make things clear: the assumption that there will soon be 10,000+ developers checking in code into the JDK is ludicrous, if the Netscape story taught us anything.

Personally, I’d like to read a good reason why they ruled out Subversion, which has the merit to be widely known and supported by most developer tools out there.

Anyway, I feel less stupid after learning these two things, so I thought I’d share.