Many times i faced issues with installing java using rpm or other source. After that i found a better way to install java from Sun site. Using below steps i have installed java successfully many times without facing any issues. We can also install multiple version of java easily if required. Oracle has also released Java 8. To install it read article Install Java 8 in CentOS, Redhat and Fedora.
Use following step by step instructions to install or update java. I recommend to read carefully instruction for downloading java from Linux command line.
Step 1: Download Archive File
Download latest version of java from http://www.oracle.com/technetwork/java/javase/downloads/jdk7-downloads-1880260.html.
# cd /opt/ # wget --no-cookies --no-check-certificate --header "Cookie: gpw_e24=http%3A%2F%2Fwww.oracle.com%2F; oraclelicense=accept-securebackup-cookie" "http://download.oracle.com/otn-pub/java/jdk/7u60-b19/jdk-7u60-linux-i586.tar.gz"
Note: In any case if above command failed to download and you need to download java through Linux terminal, watch below screen cast ( http://screencast.com/t/wf9bQ0XjDPxT ), You are required a graphical browser.
After completing download, Extract archive using following command.
# tar xzf jdk-7u60-linux-i586.tar.gz
Step 2: Install JAVA using Alternatives
After extracting java archive file, we just need to set up to use newer version of java using alternatives. Use the following commands to do it.
# cd /opt/jdk1.7.0_60/ # alternatives --install /usr/bin/java java /opt/jdk1.7.0_60/bin/java 2 # alternatives --config java
There are 4 programs which provide 'java'. Selection Command ----------------------------------------------- * 1 /usr/lib/jvm/jre-1.6.0-openjdk/bin/java + 2 /opt/jdk1.7.0_51/bin/java 3 /opt/jdk1.7.0_55/bin/java 4 /opt/jdk1.7.0_60/bin/java Enter to keep the current selection[+], or type selection number: 4 [Press Enter]
Now you may also required to setup javac and jar commands path using alternatives
# alternatives --install /usr/bin/jar jar /opt/jdk1.7.0_60/bin/jar 2 # alternatives --install /usr/bin/javac javac /opt/jdk1.7.0_60/bin/javac 2 # alternatives --set jar /opt/jdk1.7.0_60/bin/jar # alternatives --set javac /opt/jdk1.7.0_60/bin/javac
Step 3: Check JAVA Version
Use following command to check which version of java is currently being used by system.
# java -version
java version "1.7.0_60" Java(TM) SE Runtime Environment (build 1.7.0_60-b19) Java HotSpot(TM) Client VM (build 24.60-b09, mixed mode)
Step 4: Setup Environment Variables
Most of java based application’s uses environment variables to work. Use following commands to set up it.
- Setup JAVA_HOME Variable
# export JAVA_HOME=/opt/jdk1.7.0_60
- Setup JRE_HOME Variable
# export JRE_HOME=/opt/jdk1.7.0_60/jre
- Setup PATH Variable
# export PATH=$PATH:/opt/jdk1.7.0_60/bin:/opt/jdk1.7.0_60/jre/bin
I hope above steps will help you for installing java on your Linux system. You can follow above steps to install multiple version of java as same time but you can use only one version at a time.