How to install Java in Fedora Core

By default, Fedora Core 6 systems come with an old Java software installed, so you need to install a newer version of Java Runtime Environment to enjoy all the Java applications out there. In this quick guide, I will teach you how to update/install your Java Environment.

Let's begin by downloading the latest version of JRE (Java Runtime Environment) from here. Just click on the Download link where it says Java Runtime Environment (JRE) 5.0 Update, then you'll need to accept the license and download the Linux self-extracting file.

WARNING: Please remember to always replace the xx from the jre-1_5_0_xx-linux-i586.bin file with the latest version. At the moment of this guide's writing, the latest version was 09, so the file should look like this: jre-1_5_0_09-linux-i586.bin

After you have finished downloading the file, you need to move it into the /opt folder. Open a console and type:

mv jre-1_5_0_xx-linux-i586.bin /opt

Now, you will need to make this file executable so you can extract it. Follow the commands below:

cd /opt - so you can go into the /opt directory
chmod x jre-1_5_0_xx-linux-i586.bin

And now, let's run the executable file with the following command:

./jre-1_5_0_xx-linux-i586.bin

You'll be prompted with the License Agreement, hit space until you are asked if you agree or not. Type Yes and the extraction process will begin. After the extraction process is finished, just remove the binary file with the following command:

rm -rf jre-1_5_0_xx-linux-i586.bin

Now, let's put the Java plugin into your browser's plugin folder. Konqueror, Firefox and Mozilla browsers will all look into the same folder, for plugins. So type the following command:

ln -s /opt/jre1.5.0_xx/plugin/i386/ns7/libjavaplugin_oji.so /usr/lib/mozilla/plugins/libjavaplugin_oji.so

Well, now you need to make the Java executable available for the whole system, so you can run all the Java applications you encounter. Create the following file with your preferred text editor:

kwrite /etc/profile.d/java.sh

Now paste the following options into the file, remember to enter a carriage return after these lines, then save it. Remember to replace the xx with the latest version you have downloaded:

export J2RE_HOME=/opt/jre1.5.0_xx
export PATH=$J2RE_HOME/bin:$PATH

Now, type the following command to make that file available:

source /etc/profile.d/java.sh

Then type this command to see if the path is correct:

which java

You will see something like this: /opt/jre1.5.0_09/bin/java

Then type these commands:

/usr/sbin/alternatives --install /usr/bin/java java /opt/jre1.5.0_xx/bin/java 2
/usr/sbin/alternatives --config java

After you have entered the last command, you'll be asked to choose which Java software you want for your system. Just press 2 key and hit enter.

And finally, just type this command to see if everything looks good and your system has a new Java Environment:

/usr/sbin/alternatives --display java

And you can also type this command to see the version of your Java Runtime Environment:

java -version

Mine looks like this:

java version "1.5.0_09"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_09-b01)
Java HotSpot(TM) Client VM (build 1.5.0_09-b01, mixed mode, sharing)

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