OpenJDK is Sun Microsystems effort to open source Java programming language. Hence forth Java 7(JDK7) and other future releases will be called openJDK with respective version numbers.
At JavaOne 2006, Rich Green, Sun’s Executive VP of Software, said, “It’s not a question of whether, but its a question of how.” One year later at JavaOne 2007, Sun delivered on that promise and announced the source for a fully buildable JDK is now available under the GPL v2 license on java.net. This is that, so called OpenJDK.
So, its simple. Open Source Java Development Kit(JDK) is called OpenJDK.
Open source Java Development Kit(OpenJDK) is maintained by a group from open source community and java architects from sun microsystems.
