Install ubuntu jdk environment

1, download jdk8

http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

2, create a directory

 sudo mkdir /usr/lib/jvm

   Jdk directory and extract to the top

sudo tar -zxvf jdk-8u74-linux-x64.tar.gz -C /usr/lib/jvm

3, modify the system environment variables

sudo vim ~/.bashrc
or sudo gedit ~/.bashrc

  Files added at the end:

Oracle JDK Environment #set
Export the JAVA_HOME = / usr / lib / JVM / jdk1.8.0_191
Export the JRE_HOME the JAVA_HOME = $ {} / JRE
Export the CLASSPATH =:. $ {the JAVA_HOME} / lib: $ {} the JRE_HOME / lib
Export the PATH = $ {JAVA_HOME} / bin: $ PATH
 effect immediately variable

source ~/.bashrc

4, test whether the normal installation

java -version

java version "1.8.0_191"

Java(TM) SE Runtime Environment (build 1.8.0_191-b12)

Java HotSpot(TM) 64-Bit Server VM (build 25.191-b12, mixed mode)