Is the entire OpenJDK code base under the GPL?
Yes, much of the OpenJDK code is licensed under the GPL version 2 with the Classpath exception. The Java Hotspot virtual machine source code is licensed under the GPL version 2 only. All of Sun’s Java platform implementations are or will be licensed under the GPL version 2, or GPL version 2 with the Classpath exception. The GPL is endorsed by the Free Software Foundation, and is the license used by the GNU/Linux operating system. A few parts of the OpenJDK source code are licensed under other open source licenses such as the Apache license. An exception has been added to the GPL code to allow this open source code to be co-bundled with GPL code without concern of license restrictions. For more information on the Assembly Exception , please see the License section in this FAQ.