Linux Installation Configuration Jdk1.7__linux

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1. Download JDK

The Linux operating system is: centos6.5-x64

The current version of the JDK is: Java SE Development Kit 7u80

Download Address: http://download.oracle.com/otn-pub/java/jdk/7u80-b15/jdk-7u80-linux-x64.tar.gz

View Latest: Http://www.oracle.com/technetwork/java/javase/downloads/index.html

All versions archive Download address: http://www.oracle.com/technetwork/java/javase/archive-139210.html 2. Decompression installation

We install the JDK to this path:/usr/local/java
If this directory is not there (for the first time, of course not), we will create a new directory

cd/usr/local
sudo mkdir java

After the establishment, we came to just download the good compressed package directory, extract to our newly created folder inside, and modify the good name to facilitate our management

sudo tar zxvf./jdk-7u80-linux-x64.tar.gz  -c/usr/local/java
cd/usr/local/java
sudo mv jdk1.7.0_80 jdk1.7.0

3. Configure Environment Variables

VI ~/.bash_profile

Add at the end of an open file

# Export Java env
export java_home=/usr/local/java/jdk1.7.0
export JRE_HOME=/USR/LOCAL/JAVA/JDK1.7.0/JRE
Export Classpath=.:%java_home%/lib/dt.jar:%java_home%/lib/tools.jar
export path= $JAVA _home/bin: $JRE _ Home/bin: $PATH

Save the exit and enter the following command to make it effective

SOURCE ~/.bash_profile

4. Configure the default JDK (this step can be omitted in general)

The default JDK, such as OPENJDK, is already present in some Linux distributions. So to make the JDK version that we just installed become the default JDK version, we have to do the following configuration.
Execute the following command:

sudo update-alternatives--install/usr/bin/java java/usr/local/java/jdk1.7.0/bin/java-
sudo Update-alternatives--install/usr/bin/javac Javac/usr/local/java/jdk1.7.0/bin/javac-
sudo Update-alternatives--install/usr/bin/jar Jar/usr/local/java/jdk1.7.0/bin/jar-
sudo update-alternatives- Install/usr/bin/jcontrol Jcontrol/usr/local/java/jdk1.7.0/bin/jcontrol-
sudo update-alternatives--install/ USR/BIN/JPS JPS/USR/LOCAL/JAVA/JDK1.7.0/BIN/JPS 300

Note: If the above two commands do not find the path problem, just restart the computer to repeat the above two lines of code OK.

You can also use the update-alternatives--remove command to remove the path configuration as follows:

sudo update-alternatives--remove Javac/usr/local/java/jdk1.7.0/bin/javac

Perform the following code to see the current various JDK versions and configurations:

sudo update-alternatives--config java

Open a terminal and enter the following command: 5. Test

Java-version

Show Results:

Java version "1.7.0_80"
Java (tm) SE Runtime Environment (build 1.7.0_80-b15)
Java HotSpot (tm) 64-bit Server VM (bu ILD 24.80-b11, Mixed mode)

This means that the Java command is ready to run.