Back in May 2006, Sun announced during the JavaOne conference it would release Java as open source, licensed as GPL software. While it was released as GPL, it still contained about 5 percent proprietary, non-free code – the Java trap, as the FSF calls it. The FSF called to dismantle this trap, and now the IcedTea project has reached an important milestone.The IcedTea project, launched by Red Hat, built on the foundations of the GNU Classpath project to replace the proprietary code in the OpenJDK.
The latest OpenJDK binary included in Fedora 9 (x86 and x86_64) passes the rigorous Java Test Compatibility Kit (TCK). This means that it provides all the required Java APIs and behaves like any other Java SE 6 implementation – in keeping with the portability goal of the Java platform. As of writing, Fedora 9 is the only operating system to include a free and open Java SE 6 implementation that has passed the Java TCK. All of the code that makes this possible has been made available to the IcedTea project so everyone can benefit from the work.
The Java Test Compatibility Toolkit is quite the comprehensive test suite, consisting of over 1 million lines of source code, which tests if a Java implementation conforms to Java specifications. Passing the test ensures your implementation is proper Java.
This means Java is now 100% Free Software.