Install Eclipse on Ubuntu

1. download Eclipse
http://www.eclipse.org/downloads/

2. extract download file
$ tar xvfz eclipse-java-luna-SR2-linux-gtk-x86_64.tar.gz

3. move the "eclipse" entire directory to /opt/
  $ sudo mv ~/down/eclipse /opt/

4. make a script for eclipse
  $sudo vi /usr/bin/eclipse
  input followings into the script file
  

    #!/bin/sh
    export ECLIPSE_HOME=/opt/eclipse
    $ECLIPSE_HOME/eclipse $*

5. change permission to execute
  $ sudo chmod 755 /usr/bin/eclipse

6. run eclipse
  $ eclipse