Installing the JDK under Ubuntu14.04

1. Download to Oracle's website

Http://www.oracle.com/technetwork/java/javase/downloads/jdk7-downloads-1880260.html

Select Accept License and select the JDK download that fits your model.

2, unzip the file, modify the filename

$ sudo mkdir/usr/lib/jvm$ sudo tar zxvf jdk-8u51-linux-x64.tar.gz-c/usr/lib/jvm$ cd/usr/lib/jvm$ sudo mv jdk1.8.0_51 j Ava

3. Add Environment variables

$ sudo gedit ~/.BASHRC

Add the following:

Export Java_home=/usr/lib/jvm/java export JRE_HOME=${JAVA_HOME}/JRE  export classpath=.:${java_home}/lib:${jre_ Home}/lib  export Path=${java_home}/bin: $PATH  

4. Configuring the default JDK version

sudo update-alternatives--install/usr/bin/java java/usr/lib/jvm/java/bin/java  sudo update-alternatives-- Install/usr/bin/javac javac/usr/lib/jvm/java/bin/javac  sudo update-alternatives--install/usr/bin/jar jar/ Usr/lib/jvm/java/bin/jar   sudo update-alternatives--install/usr/bin/javah javah/usr/lib/jvm/java/bin/javah   sudo update-alternatives--install/usr/bin/javap javap/usr/lib/jvm/java/bin/javap 300   

And then execute

sudo update-alternatives--config java

If you first install the JDK, you will be prompted

There is only one alternative in link Group Java (providing/usr/bin/java):/usr/lib/jvm/java/bin/java no configuration required.

For non-initial installation, there will be different versions of the JDK option.

5. Testing

$ Java-versionjava Version "1.8.0_51" Java (tm) SE Runtime Environment (build 1.8.0_51-b16) Java HotSpot (tm) 64-bit Server V M (build 25.51-b03, Mixed mode)

Installing the JDK under Ubuntu14.04