Linux Java

Oracle Java 8 JDK - Java Development Kit - apt-get install method

Add repository, this will also display how to install different version of Oracle Java

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java8-installer #this and other packages become available after refreshing repository

Oracle Java 7 - zip file install

This will treat how to install Oracle Java in Ubuntu. This method does not use any package management software. Use a link in the references section for other options.

Download the 32-bit or 64-bit Linux from "http://www.oracle.com/technetwork/java/javase/downloads/index.html" "compressed binary file" - it has a ".tar.gz" file extension.

Uncompress it

tar -xvf jdk-7u80-linux-x64.tar.gz (32-bit)
tar -xvf jdk-7u80-linux-x64.tar.gz (64-bit)

The JDK 7 package is extracted into ./jdk1.7.0_80 directory.

Now move the JDK 7 directory to /usr/lib

sudo mkdir -p /usr/lib/jvm
sudo mv ./jdk1.7.0_80 /usr/lib/jvm/

Now run

sudo update-alternatives --install "/usr/bin/java" "java" "/usr/lib/jvm/jdk1.7.0_80/bin/java" 1
sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/lib/jvm/jdk1.7.0_80/bin/javac" 1
sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/lib/jvm/jdk1.7.0_80/bin/javaws" 1

This will assign Oracle JDK a priority of 1, which means that installing other JDKs will replace it as the default. Be sure to use a higher priority if you want Oracle JDK to remain the default.

Correct the file ownership and the permissions of the executables:

sudo chmod a+x /usr/bin/java
sudo chmod a+x /usr/bin/javac
sudo chmod a+x /usr/bin/javaws
sudo chown -R root:root /usr/lib/jvm/jdk1.7.0_80

Run

sudo update-alternatives --config java

You will see output similar to the one below - choose the number of jdk1.7.0_80 - for example 3 in this list (unless you have have never installed Java installed in your computer in which case a sentence saying "There is nothing to configure" will appear):

$ 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-oracle1/bin/java   1047      auto mode
  1            /usr/bin/gij-4.6                       1046      manual mode
  2            /usr/lib/jvm/java-6-oracle1/bin/java   1047      manual mode
  3            /usr/lib/jvm/jdk1.7.0_80/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_80/bin/java to provide /usr/bin/java (java) in manual mode

Repeat the above for:

sudo update-alternatives --config javac
sudo update-alternatives --config javaws

Verify

$ java -version
java version "1.7.0_80"
Java(TM) SE Runtime Environment (build 1.7.0_80-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.80-b11, mixed mode)

References

• Java Ubuntu official wiki