OpenJDK is an open source implementation of the Java(TM) 2 Platform Standard Edition Development Kit. This package is built with the IcedTea build project and includes tools for developing, testing, and running programs written in Java. apache-ant is a required dependency and you have to install it before you build openjdk. However, you do not need to install Oracle's jdk, since it's only a runtime dependency. This script imports the security certificates also found in Oracle's jdk. You can override this behavior by invoking the script like this: KEYSTORE_NO_IMPORT=YES ./openjdk.SlackBuild The above line, however, will cause some programs to fail to estab- lish secure connections. Before installing this package please consider any other jdk's/jre's that you have already installed as they may cause conflicts with the PATH, JAVA_HOME and MANPATH variables. After installing the package you will need to logout/reboot your machine as it will add new files to the /etc/profile.d folder. This script may take a couple of hours to finish and will require about 11 GB of disk space for its temporary directory. It defaults to "/tmp/SBo" and you may redefine it like this: TMP=/your/temporary/dir ./openjdk.SlackBuild If you get an error like Internal compiler error: java.lang.NullPointerException at org.eclipse.jdt.internal.compiler.ReadManager.run(ReadManager.java:166) simply run the build again. This happens early so it shouldn't be that of a problem. At least 1 out of 5 runs so far have always succeded.