Setting SUN Java for Ubuntu.

First create directory for Java

 ahmed@ahmed-server:~/sun-java# mkdir -p /usr/lib/jvm/
 ahmed@ahmed-server:~/sun-java# tar xvzf jdk1.7.0_75.tgz -C /usr/lib/jvm/

Setting Alternatives

 ahmed@ahmed-server:~/sun-java# sudo update-alternatives --install "/usr/bin/java" "java" "/usr/lib/jvm/jdk1.7.0_75/bin/java" 1
 ahmed@ahmed-server:~/sun-java# sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/lib/jvm/jdk1.7.0_75/bin/javac" 1
 ahmed@ahmed-server:~/sun-java# sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/lib/jvm/jdk1.7.0_75/bin/javaws" 1
 update-alternatives: using /usr/lib/jvm/jdk1.7.0_75/bin/javaws to provide /usr/bin/javaws (javaws) in auto mode.

Make sure we have the right permission.

 ahmed@ahmed-server:~/sun-java# sudo chmod a+x /usr/bin/java
 ahmed@ahmed-server:~/sun-java# sudo chmod a+x /usr/bin/javac
 ahmed@ahmed-server:~/sun-java# sudo chmod a+x /usr/bin/javaws
 ahmed@ahmed-server:/usr/lib/jvm# sudo chown -R root:root /usr/lib/jvm/jdk1.7.0_75

Configuration of Alternatives

 ahmed@ahmed-server:/usr/lib/jvm# sudo update-alternatives --config java
 There are 3 choices for the alternative java (providing /usr/bin/java).

   Selection    Path                                            Priority   Status
 ------------------------------------------------------------
 * 0            /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/java   1061      auto mode
   1            /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/java   1061      manual mode
   2            /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java   1051      manual mode
   3            /usr/lib/jvm/jdk1.7.0_75/bin/java                1         manual mode

 Press enter to keep the current choice[*], or type selection number: 3
 update-alternatives: using /usr/lib/jvm/jdk1.7.0_75/bin/java to provide /usr/bin/java (java) in manual mode.

 ahmed@ahmed-server:/usr/lib/jvm# sudo update-alternatives --config javac
 There are 2 choices for the alternative javac (providing /usr/bin/javac).

   Selection    Path                                         Priority   Status
 ------------------------------------------------------------
 * 0            /usr/lib/jvm/java-7-openjdk-amd64/bin/javac   1051      auto mode
   1            /usr/lib/jvm/java-7-openjdk-amd64/bin/javac   1051      manual mode
   2            /usr/lib/jvm/jdk1.7.0_75/bin/javac            1         manual mode

 Press enter to keep the current choice[*], or type selection number: 2
 update-alternatives: using /usr/lib/jvm/jdk1.7.0_75/bin/javac to provide /usr/bin/javac (javac) in manual mode.
 ahmed@ahmed-server:/usr/lib/jvm# sudo update-alternatives --config javawc
 update-alternatives: error: no alternatives for javawc.

Checking version

 ahmed@ahmed-server:/usr/lib/jvm# java -version
 java version "1.7.0_75"
 Java(TM) SE Runtime Environment (build 1.7.0_75-b13)
 Java HotSpot(TM) 64-Bit Server VM (build 24.75-b04, mixed mode)
 ahmed@ahmed-server:/usr/lib/jvm# javac -version
 javac 1.7.0_75
 ahmed@ahmed-server:/usr/lib/jvm#

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