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This tutorial will cover the installation of

32-bit and 64-bit Oracle Java 7 (currently version number 1.7.0_05)
 JDK/JRE on 32-bit and 64-bit Ubuntu operating systems.

1 2	32-bit and 64-bit Oracle Java 7 (currently version number 1.7.0_05) JDK/JRE on 32-bit and 64-bit Ubuntu operating systems.

These instructions will also work on Debian and Linux Mint.

Check to see if your Ubuntu Linux operating system architecture is 32-bit or 64-bit, open up a terminal and run the following command below.

 uname -a

uname -a

Java Version

 java -version

1	java -version

If you have OpenJDK installed on your system it may look like this

 java version "1.6.0_21"
OpenJDK Runtime Environment (IcedTea6 1.10pre) (6b21~pre1-0lucid1)
OpenJDK 64-Bit Server VM (build 19.0-b09, mixed mode)

java version "1.6.0_21"

OpenJDK Runtime Environment (IcedTea6 1.10pre) (6b21~pre1-0lucid1)

OpenJDK 64-Bit Server VM (build 19.0-b09, mixed mode)

If you have OpenJDK installed on your system, you have the wrong vendor version of Java installed for this exercise.
Completely remove the OpenJDK/JRE from the system if necessary
This will prevent system conflicts and confusion between different vendor versions of Java. For example, if you have the OpenJDK/JRE installed on your system, you can remove it by typing the following at the command line:

  sudo apt-get purge openjdk-\*

1	sudo apt-get purge openjdk-\*

This command will completely remove OpenJDK/JRE from your system
Create a directory to put your Oracle Java JDK and JRE binaries in, open up a terminal and create the directory /usr/local/java

sudo mkdir -p /usr/local/java

1	sudo mkdir -p /usr/local/java

Download the Oracle Java JDK/JRE for Linux. Make sure you select the correctcompressed binaries for your system architecture 32-bit or 64-bit (which end in tar.gz).

For example, if you are on Ubuntu Linux 32-bit operating system download 32-bit Oracle Java binaries.
For example, if you are on Ubuntu Linux 64-bit operating system download 64-bit Oracle Java binaries.

Copy the Oracle Java binaries into the /usr/local/java directory
In most cases, the Oracle Java binaries are downloaded to: /home/“your_user_name”/Downloads.

32-bit Oracle Java on 32-bit Ubuntu Linux installation instructions:

 sudo -s cp -r jdk-7u5-linux-i586.tar.gz /usr/local/java 
sudo -s cp -r jre-7u5-linux-i586.tar.gz /usr/local/java
cd /usr/local/java

sudo -s cp -r jdk-7u5-linux-i586.tar.gz /usr/local/java

sudo -s cp -r jre-7u5-linux-i586.tar.gz /usr/local/java

cd /usr/local/java

	#64-bit Oracle Java on 64-bit Ubuntu Linux installation instructions:
	cd /home/<strong>"your_user_name"</strong>/Downloads
	sudo -s cp -r jdk-7u5-linux-x64.tar.gz /usr/local/java
	sudo -s cp -r jre-7u5-linux-x64.tar.gz /usr/local/java
	cd /usr/local/java

#64-bit Oracle Java on 64-bit Ubuntu Linux installation instructions:

cd /home/<strong>"your_user_name"</strong>/Downloads

sudo -s cp -r jdk-7u5-linux-x64.tar.gz /usr/local/java

sudo -s cp -r jre-7u5-linux-x64.tar.gz /usr/local/java

cd /usr/local/java

Run the following commands on the downloaded Oracle Java tar.gz files. Make sure to do this as root in order to make them executable for all users on your system.
32-bit Oracle Java on 32-bit Ubuntu Linux installation instructions:

sudo -s chmod a+x jdk-7u5-linux-i586.tar.gz
sudo -s chmod a+x jre-7u5-linux-i586.tar.gz

# 64-bit Oracle Java on 64-bit Ubuntu Linux installation instructions:
sudo -s chmod a+x jdk-7u5-linux-x64.tar.gz
sudo -s chmod a+x jre-7u5-linux-x64.tar.gz

sudo -s chmod a+x jdk-7u5-linux-i586.tar.gz

sudo -s chmod a+x jre-7u5-linux-i586.tar.gz

# 64-bit Oracle Java on 64-bit Ubuntu Linux installation instructions:

sudo -s chmod a+x jdk-7u5-linux-x64.tar.gz

sudo -s chmod a+x jre-7u5-linux-x64.tar.gz

Unpack the compressed Java binaries, in the directory /usr/local/java

	sudo -s tar xvzf jdk-7u5-linux-i586.tar.gz

1	sudo -s tar xvzf jdk-7u5-linux-i586.tar.gz

	sudo -s tar xvzf jre-7u5-linux-i586.tar.gz

1	sudo -s tar xvzf jre-7u5-linux-i586.tar.gz

64-bit Oracle Java on 64-bit Ubuntu Linux installation instructions:

sudo -s tar xvzf jdk-7u5-linux-x64.tar.gz
 sudo -s tar xvzf jre-7u5-linux-x64.tar.gz

1 2	sudo -s tar xvzf jdk-7u5-linux-x64.tar.gz sudo -s tar xvzf jre-7u5-linux-x64.tar.gz

Double-check your directories. At this point, you should have two uncompressed binary directories in /usr/local/java for the Java JDK/JRE listed as:

	ls -a

ls -a

jdk1.7.0_05
jre1.7.0_05
<strong>Edit the system PATH file /etc/profile and add the following system variables to your system path</strong>. Use nano, gedit or any other text editor, as root, open up /etc/profile.

jdk1.7.0_05

jre1.7.0_05

<strong>Edit the system PATH file /etc/profile and add the following system variables to your system path</strong>. Use nano, gedit or any other text editor, as root, open up /etc/profile.

sudo gedit /etc/profile+
sudo nano /etc/profile
JAVA_HOME=/usr/local/java/jdk1.7.0_05
PATH=$PATH:$HOME/bin:$JAVA_HOME/bin
JRE_HOME=/usr/local/java/jre1.7.0_05
PATH=$PATH:$HOME/bin:$JRE_HOME/bin
export JAVA_HOME
export JRE_HOME
export PATH

sudo gedit /etc/profile+

sudo nano /etc/profile

JAVA_HOME=/usr/local/java/jdk1.7.0_05

PATH=$PATH:$HOME/bin:$JAVA_HOME/bin

JRE_HOME=/usr/local/java/jre1.7.0_05

PATH=$PATH:$HOME/bin:$JRE_HOME/bin

export JAVA_HOME

export JRE_HOME

export PATH

Inform your Ubuntu Linux system where your Oracle Java JDK/JRE is located. This will tell the system that the new Oracle Java version is available for use.this command notifies the system that Oracle Java JRE is available for use

	sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jre1.7.0_05/bin/java" 1

1	sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jre1.7.0_05/bin/java" 1

	sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/local/java/jdk1.7.0_05/bin/javac" 1

1	sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/local/java/jdk1.7.0_05/bin/javac" 1

this command notifies the system that Oracle Java JDK is available for use

	sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/local/java/jdk1.7.0_05/bin/javaws" 1

1	sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/local/java/jdk1.7.0_05/bin/javaws" 1

this command notifies the system that Oracle Java Web start is available for use,
Inform your Ubuntu Linux system that Oracle Java JDK/JRE must be the default Java

	sudo update-alternatives --set java /usr/local/java/jre1.7.0_05/bin/java
sudo update-alternatives --set javac /usr/local/java/jdk1.7.0_05/bin/javac
sudo update-alternatives --set javaws /usr/local/java/jdk1.7.0_05/bin/javaws
. /etc/profile

sudo update-alternatives --set java /usr/local/java/jre1.7.0_05/bin/java

sudo update-alternatives --set javac /usr/local/java/jdk1.7.0_05/bin/javac

sudo update-alternatives --set javaws /usr/local/java/jdk1.7.0_05/bin/javaws

. /etc/profile

Note your system-wide PATH /etc/profile file will reload after reboot of your Ubuntu Linux system.
Test to see if Oracle Java was installed correctly on your system. Run the following commands and note the version of Java:

java -version

1	java -version

This command displays the version of java running on your system
A successful installation of 32-bit Oracle Java will display

You should receive a message which displays:

java version "1.7.0_05"
Java(TM) SE Runtime Environment (build 1.7.0_05-b05)
 Java HotSpot(TM) Server VM (build 23.1-b03, mixed mode)
 javac -version

java version "1.7.0_05"

Java(TM) SE Runtime Environment (build 1.7.0_05-b05)

Java HotSpot(TM) Server VM (build 23.1-b03, mixed mode)

javac -version

This command lets you know that you are now able to compile Java programs from the terminal.
You should receive a message which displays:
javac 1.7.0_05
A successful installation of Oracle Java 64-bit will display
java -version
This command displays the version of java running on your system
You should receive a message which displays:

java version "1.7.0_05" Java(TM) SE Runtime Environment (build 1.7.0_05-b20) Java HotSpot(TM)
 64-Bit Server VM (build 23.0-b21, mixed mode)

 javac -version 
This command lets you know that you are now able to compile Java programs from the terminal.
 You should receive a message which displays:
 javac 1.7.0_05

java version "1.7.0_05" Java(TM) SE Runtime Environment (build 1.7.0_05-b20) Java HotSpot(TM)

64-Bit Server VM (build 23.0-b21, mixed mode)

javac -version

This command lets you know that you are now able to compile Java programs from the terminal.

You should receive a message which displays:

javac 1.7.0_05

Congratulations, you just installed Oracle Java on your Linux system.

Now reboot your Ubuntu Linux system.
Afterwards, your system will be fully configured for running and developing Java programs.