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               Java(tm) Binary Kernel Support for Linux v1.01

               ----------------------------------------------

Linux beats them ALL! While all other OS's are TALKING about direct

support of Java Binaries in the OS, Linux is doing it!

You execute Java classes as you would any other executable, after a few

small details:

        1) You MUST FIRST install the Java Developers Kit for Linux.

           The Java on Linux HOWTO gives the details on getting and

           installing this. This HOWTO can be found at:

                ftp://sunsite.unc.edu/pub/Linux/docs/HOWTO/Java-HOWTO

           If you install the JDK in a location other than the suggested

           directory of /usr/local/java, then you will need to tell the

           kernel where you put the Java interpreter.

           There are two ways to do this.

           One, edit fs/binfmt_java.c file and make the needed change to

           the _PATH_JAVA definition at the top of that file.

           Two, as root, issue the command:

         echo "/path/to/java/interpreter" > /proc/sys/kernel/java-interpreter

           (Currently, this does not work if you're using a module for

            Java support.)

        2) You must chmod the '*.class' files you wish to execute with

           the execute bit. This is not normally (till now) done with

           '.class' files.

        3) You must optionally export a CLASSPATH environment variable,

           if you plan to use Java applications installed outside of

           /usr/local/java/classes/*.

        4) Either compile your kernel with Java support builtin, or

           as a loadable module. If a module, load it with insmod or

           kerneld.

To test your new setup, enter in the following simple Java app, and name

it "HelloWorld.java":

        class HelloWorld {

                public static void main(String args[]) {

                        System.out.println("Hello World!");

                }

        }

Now compile the application with:

        /usr/local/java/bin/javac HelloWorld.java

Set the executable permissions of the binary file, with:

        chmod 755 HelloWorld.class

And then execute it:

        ./HelloWorld.class

Yes, it's JUST THAT EASY! ;-)

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Nope, I didn't forget about Java Applets! ;-)

While this may not be the best way to do this, it works!

Take any html file used with the Java appletviewer (like the

demo/Blink/example1.html file), and:

        1) Insert a new first line of:

           Make sure the '<' is the first character in the file. This

           will be treated as a valid HTML comment outside of this

           Java Applet support, so the modified file can still be used

           with all known browsers.

        2) If you install the JDK in a location other than the suggested

           directory of /usr/local/java, then you will need to tell the

           kernel where you put the Java appletviewer.

           There are two ways to do this.

           One, edit fs/binfmt_java.c file and make the needed change to

           the _PATH_APPLET definition at the top of that file.

           Two, as root, issue the command:

        echo "/path/to/java/appletviewer" > /proc/sys/kernel/java-appletviewer

           (Currently, this does not work if you're using a module for

            Java support.)

        3) You must chmod the '*.html' files you wish to execute with

           the execute bit. This is not normally (till now) done with

           '.html' files.

        4) And then execute it.

Brian A. Lantz

brian@lantz.com

(/proc/sys/kernel/java-* support by Mike Shaver (shaver@ingenia.com))