Kicking off at the start of the week, the Oracle vs. Google court case over Java brought CEOs Larry Ellison and Larry Page to the stand, and has now turned the courtroom into a classroom. On day four of the court case, both Oracle and Google offered their explanations of Java and its APIs. It was Mark Reinhold who took the stand this time around, Oracle’s architect for the Java platform. He outlined the distinction between the Java language, which is freely available for use, and the Java APIs, detailed specifically for valid uses of the Java language.

Under fire for alleged patent violations, Google insists Java APIs should not be copyrighted. Google trial counsel Daniel Purcell cross-examined Reinhold, blurring the clear lines he’d drawn when he got Reinhold to acknowledge that some 10 percent to 20 percent of Java APIs are from contributors outside Sun or Oracle, none of whom are paid, implying that some Java API copyrights aren’t valid.

But once Joshua Bloch, chief architect at Google, took the stand, he admitted that programming is a creative process, supporting the notion that code can in fact qualify for copyright protection. Under questioning from Oracle, Bloch also acknowledged that the Java API he created for Android was near identical to a similar API he’d written for Java while working for Sun. This is where Oracle hopes to pin Google for copyright infringement, but there’s still more parameters to be established by both sides before this case comes to a close.

More copyright questions in a world going open source

The question of Java’s copyrightable content is one that could change the way open source material can be used and monetized, and these are questions RIM may soon have to consider as the BlackBerry maker may open-source its mobile OS. In its difficulty keeping up with Android’s open platform and the growth of iOS, RIM is losing relevancy with its device-OS combo. Should RIM open up the BlackBerry 10 OS to the developer community, they’d be following a path similar to HP, which also faced an unbearable amount of competition from Android and iOS with its webOS platform.

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