How to install java jdk on Ubuntu? here i provide few steps to demonstrate how it’s work.

Installation Setup

1 ) Issue following command to find out current jdk version in apt-get

apt-cache search jdk

2 ) Install java JDK and JRE with apt-get install

apt-get install sun-java6-jdk sun-java6-jre

3 ) Ubuntu will auto download necessary file from web for installation.

Do you want to continue [Y/n]? y
Get:1 http://my.archive.ubuntu.com hardy/main java-common 0.28ubuntu3 [78.2kB]
Get:2 http://my.archive.ubuntu.com hardy/multiverse sun-java6-jre 6-06-0ubuntu1 [6334kB]
Get:3 http://my.archive.ubuntu.com hardy/main odbcinst1debian1 2.2.11-16build1 [66.2kB]
Get:4 http://my.archive.ubuntu.com hardy/main unixodbc 2.2.11-16build1 [289kB]
Get:5 http://my.archive.ubuntu.com hardy/multiverse sun-java6-bin 6-06-0ubuntu1 [27.3MB] 
Get:6 http://my.archive.ubuntu.com hardy/multiverse sun-java6-jdk 6-06-0ubuntu1 [9625kB] 
85% [6 sun-java6-jdk 3208002/9625kB 33%]


4) After installation done, jdk and jre will install at /usr/lib/jvm/java-6-sun-1.6.0.06

5) Ubuntu help to create a java symbolic link and put in /usr/bin for shortcut access

4 ) type java -version, DONE !!

Post-Installation Setup

Set JAVA_HOME into environment variable

Copy following statement and append to /etc/profile or .bashrc file, make system set JAVA_HOME into system environment variable.

export JAVA_HOME="/usr/lib/jvm/java-6-sun-1.6.0.06"

P.S Please visit How to install JDK on Fedora Core, if you want to know how to install java jdk manually.

Any Java questions or problems? please post at this JavaNullPointer.com forum, see you there ~