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.
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uname -a or file /sbin/init
Linux caochu-Inspiron-N5110 3.13.0-32-generic #57-Ubuntu SMP Tue Jul 15 03:51:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
Check if you have Java installed on your system. To do this, you will have to run the Java version command from terminal.
Type/Copy/Paste:java -versio
If you have OpenJDK installed on your system, you have the wrong vendor version of Java installed for this exercise.
sudo apt-get purge openjdk-*
Download the Oracle Java JDK for Linux.
Unpack the compressed Java binaries, in the directory /usr/local/java8
Scroll down to the end of the file using your arrow keys and add the following lines below to the end of your./etc/profile file:
export JAVA_HOME=/usr/local/java8/jdk1.8.0_73
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib
export PATH=${JAVA_HOME}/bin:$PATH source /etc/profile
Configure default JDK version :
sudo update-alternatives --install /usr/bin/java java /usr/local/java8/jdk1.8.0_73/bin/java 300
sudo update-alternatives --install /usr/bin/javac javac /usr/local/java8/jdk1.8.0_73/bin/javac 300
sudo update-alternatives --install /usr/bin/jar jar /usr/local/java8/jdk1.8.0_73/bin/jar 300
sudo update-alternatives --install /usr/bin/javah javah /usr/local/java8/jdk1.8.0_73/bin/javah 300
sudo update-alternatives --install /usr/bin/javap javap /usr/local/java8/jdk1.8.0_73/bin/javap 300
sudo update-alternatives --config java
Test
java -version
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