First download jdk-7-linux-i586.tar.gz on the official website
Enter the command tar-zxvf./jdk-7-linux-i586.tar.gz in the terminal
Then sudo mkdir/usr/lib/JVM
Then sudo mV./jdk1.7.0.03/usr/lib/JVM/
Then set the environment variable
Sudo VI ~ /. Bashrc
Add
Export java_home =/usr/lib/JVM/jdk1.7.0 _ 03
Export jre_home =$ {java_home}/JRE
Export classpath =. :$ {java_home}/lib :$ {jre_home}/lib
Export path =$ {java_home}/bin: $ path
Save and exit
Enter source ~ on the terminal ~ /. Bashrc to make it take effect
Last run
Sudo Update-alternatives -- install/usr/bin/Java/usr/lib/JVM/jdk1.7.0 _ 03/bin/Java 300
Sudo Update-alternatives -- install/usr/bin/javac/usr/lib/JVM/jdk1.7.0 _ 03/bin/javac 300
Sudo Update-alternatives -- config Java
Only one JDK version is found
Running Java-version shows normal, JDK is installed successfully
Source: http://blog.csdn.net/chendi9010/article/details/7335795