Note: the terminal commands in this how-to possibly refer to an older version of JRE. When there's a newer version, you can simply adapt the file names in the terminal commands.

This how-to has been written for JRE 6 update 18 (32 bit version).

1. Go to the folder opt, with the following command:

Applications - Accessories - Terminal

Type (use copy/paste: rapidly click three times on the blue line, in order to select the entire line).

cd /opt

Press Enter.

2. Create a new subfolder, with the following command line. Type (copy/paste):

sudo mkdir java

Press Enter.

Type your password. You won't see anything, not even dots, this is normal. Press Enter.

3. Go to the new folder, with the following command. Type (copy/paste):

cd java

Press Enter.

4. Create a new subfolder, with the following command. Type (copy/paste):

sudo mkdir 32

Press Enter.

5. Move the JRE file that you just downloaded, into this newest folder, with the following command. Type (copy/paste):

sudo mv ~/jre-6u18-linux-i586.bin /opt/java/32

Press Enter.

6. Make the file executable, with the following command. Type (copy/paste):

sudo chmod 755 /opt/java/32/jre-6u18-linux-i586.bin

Press Enter.

Now you're going to install JRE, by executing this file.

7. First, go to the new folder, with the following command. Type (copy/paste):

cd /opt/java/32

Press Enter.

8. Execute the file, with the following command. Type (copy/paste):

sudo ./jre-6u18-linux-i586.bin

Press Enter.

Now the license agreement appears. Press as many times on the space bar, until you see the following text (or hit 'q'): Do you agree to the above license terms? [yes or no]

Type:

yes

Press Enter.

Inform the system and make the new JRE the default

9. Now you'll want to tell the system, that there's a new Java version available.

Type (copy/paste):

sudo update-alternatives --install "/usr/bin/java" "java" "/opt/java/32/jre1.6.0_18/bin/java" 1

Press Enter.

Note: are you updating from a previous Java version, which you have removed manually? Then you'll need to execute the above command twice, because you'll get an error message the first time.

10. Tell the system, that the new Java must be the default:

Type (copy/paste):

sudo update-alternatives --set java /opt/java/32/jre1.6.0_18/bin/java

Press Enter.

Install the Firefox plugin

11. Installing the Firefox plugin is simple. First execute the following command, in order to create a certain folder (if it doesn't exist already).

Type in the terminal (copy/paste):

mkdir ~/.mozilla/plugins

Press Enter.

If it exists already, you'll see a notification of that.

12. Now remove the IcedTea plugin, if it has been installed.

Type (copy/paste):

sudo apt-get remove icedtea6-plugin

Press Enter.

13. Remove a former version of the Java plugin.

Type (copy/paste):

rm ~/.mozilla/plugins/libjavaplugin_oji.so

Press Enter.

And then type (copy/paste):

rm ~/.mozilla/plugins/libnpjp2.so

Press Enter.

14. Now you can install the plugin, by creating a symbolic link (you tell Firefox, where the plugin is located).

For Firefox 3.5 and older, type (copy/paste):

ln -s /opt/java/32/jre1.6.0_18/plugin/i386/ns7/libjavaplugin_oji.so ~/.mozilla/plugins/

For Firefox 3.6 and newer, type (copy/paste):

ln -s /opt/java/32/jre1.6.0_18/lib/i386/libnpjp2.so ~/.mozilla/plugins/

Press Enter.

Final check

Now close and restart Firefox. Check if everything has succeeded. Type in the url bar of Firefox (not in the terminal!):

about:plugins

Press Enter.

And scroll down, until you see something approximately similar to this: Java(TM) Plug-in 1.6.0_18

You can also use this website: http://java.com/en/download/installed.jsp

You can call up the Control Panel as follows (in each user account):

Type (copy/paste):

/opt/java/32/jre1.6.0_18/bin/ControlPanel

Press Enter.

It looks like Sun Java is put into the partner repository. You can now regain it simply by enabling that repository and updating. Search for “sun-java” and there you have it!

Source: http://sites.google.com/site/easylinuxtipsproject/java