You need to run sh on the bin file you downloaded in order to expand it. If you are downloading SDK version 1.4.2 then the command would be: sh j2sdk-1_4_2_01-linux-i586-rpm.bin
This will bring up another long license screen. Press the space bar a couple of hundred times and you will eventually get to a question along the lines of "Do you agree to the above license terms" to which you type in 'yes' (you already gave up your soul in step 1, so there isn't much to lose). This will cause the script you executed to decompress a .rpm file.
To install the RPM file type in "urpmi X" where X is the rpm filename. In the case of 1.4.2 this was "urpmi j2sdk-1_4_2_01-linux-i586.rpm". This will cause files in the RPM to be installed, somewhere.
Step 3 - Setting Up Your Java Environment -
As your normal non-root identity use your favorite editor to open ~/.bashrc Add in the following path declaration "PATH=$PATH:X:" where X is the location of the bin directory. In my machine this is "PATH=$PATH:/usr/java/j2sdk1.4.2_01/jre/bin:".
Add in the following JAVA_HOME declaration (this tells Java programs where to find the files they need) "JAVA_HOME=X", this is the same X as before so on my system it is "JAVA_HOME=/usr/java/j2sdk1.4.2_01/jre/bin"
You need to link the Java plugin file into your Mozilla installation. The command is "ln -s Y/plugin/i386/ns610/libjavaplugin_oji.so Z/plugins/libjavaplugin_oji.so". Where Y is the jre installation directory and Z is the mozilla installation directory. On my machine the command is "ln -s /usr/java/j2sdk1.4.2/jre/plugin/i386/ns610/libjavaplugin_oji.so /usr/lib/mozilla-1.3.1/plugins/libjavaplugin_oji.so"
NOTE: If you are using Mozilla 1.4 or higher you need to get the .so file from the /ns610-gcc32 directory not the /ns610 directory.
I apologize, but I don't quite understand your question. I am familiar with using Java under Linux since that is my primary development environment. If you can provide more details about what you have done so far and ask a clear question about what you need help with, I will be more than happy to share my knowledge, however limited it may be. Be sure to post an exact copy of your .bash_profile and/or .bashrc files as well as anything else you think might be helpful for us to understand what your problem. Good luck! Layne