Install Oracle JDK in LinuxMint Maya or Ubuntu 12.04 LTS

This primarily describes setup required for Android development on 64 bit LinuxMint Maya what is very much the same as Ubuntu 12.04 but with usable window manager. For those two popular distros we have OpenJDK in repository and we can easily install it using apt-get from terminal or GUI Software Manager. But for Android development only Oracle JDK is supported and Android SDK is 32 bit what implies:

sudo apt-get install ia32-libs

Otherwise we will get confusing error message that for example adb was not found and we attempted to run it.
Current version of Oracle JDK can be downloaded from here http://www.oracle.com/technetwork/java/javase/downloads/index.html
For example we select jdk-7u7-linux-x64.tar.gz accept license and download it using Firefox. When download finishes we typically check signature of it and that is done from terminal, so cd to Downloads and run:

$ md5sum jdk-7u7-linux-x64.tar.gz
15f4b80901111f002894c33a3d78124c  jdk-7u7-linux-x64.tar.gz

Here I do Google search on md5 to be sure that I downloaded right archive. Then we unpack archive simply right clicking on it and selecting Extract Here. That creates directoru jdk1.7.0_07 in Downloads. JDK should be in /usr/lib/jvm unless we want to specify execution path every time, for example this is how it looks on my box:

/usr/lib/jvm $ ls -l
total 20
lrwxrwxrwx 1 root root   24 Oct 31 15:39 default-java -> java-1.6.0-openjdk-amd64
lrwxrwxrwx 1 root root   24 Oct 31 15:39 java-1.6.0-openjdk -> java-1.6.0-openjdk-amd64
lrwxrwxrwx 1 root root   20 Oct 31 15:39 java-1.6.0-openjdk-amd64 -> java-6-openjdk-amd64
lrwxrwxrwx 1 root root   24 Oct 31 15:39 java-6-openjdk -> java-1.6.0-openjdk-amd64
drwxr-xr-x 7 root root 4096 Nov  4 00:00 java-6-openjdk-amd64
drwxr-xr-x 3 root root 4096 May  3  2012 java-6-openjdk-common
lrwxrwxrwx 1 root root   24 Nov  1 11:26 java-6-oracle -> /usr/lib/jvm/jdk1.6.0_37
drwxr-xr-x 5 root root 4096 May  3  2012 java-7-openjdk-amd64
lrwxrwxrwx 1 root root   24 Oct 31 16:52 java-7-oracle -> /usr/lib/jvm/jdk1.7.0_07
drwxr-xr-x 8 root root 4096 Nov  1 11:22 jdk1.6.0_37
drwxr-xr-x 8 root root 4096 Aug 29 03:12 jdk1.7.0_07

In order to move jdk1.7.0_07 from downloads we can use

sudo mv jdk1.7.0_07 /usr/lib/jvm/

we are doing that from terminal in Downloads, or maybe start caja or gnome as root and do it from GUI. If we are in GUI we recursively change ownership to root using properties and if we are doing it from terminal:

sudo chown -R root:root /usr/lib/jvm/jdk1.7.0_07

Now we need symlink which we use later to switch between different versions of Java:

sudo ln -s /usr/lib/jvm/jdk1.7.0_07 /usr/lib/jvm/java-7-oracle

now we can install runtime and compiler:

sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/java-7-oracle/jre/bin/java 2
sudo update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/java-7-oracle/bin/javac 1

That allows us to configure runtime and compiler respectively using the following two:

sudo update-alternatives --config java
sudo update-alternatives --config javac

we need simply to type number of desired version and hit enter. To check what we are actually running we can execute:

javac -version
java -version