Detailed steps for downloading, installing, and configuring jdk1.8 on the Linux system using the command line (for example, CentOS) __centos

1. Log in with the root user system, if the system already has other versions of the JDK, you can uninstall the relevant software package, command:

RPM-E--nodeps Jdkname

Where jdkname can not include character segments for version information, you can view them by using the following command:

Rpm-qa | grep JDK

2. Download the jdk1.8. rpm file from the Oracle website, address if http://download.oracle.com/otn-pub/java/jdk/8u25-b17/jdk-8u25-linux-x64.rpm? AUTHPARAM=1421409865_906DD11E2CABEF6E49C0A4E4B1A92B3A, the command is:

cd/user/local--first enter the directory where the package is saved

wget http://download.oracle.com/otn-pub/java/jdk/8u25-b17/jdk-8u25-linux-x64.rpm? authparam=1421409865_906dd11e2cabef6e49c0a4e4b1a92b3a

After downloading, you can use the LS command to see the download to the file name jdk-8u25-linux-x64.rpm? AUTHPARAM=1421409865_906DD11E2CABEF6E49C0A4E4B1A92B3A, can be renamed before installation:

MV jdk-8u25-linux-x64.rpm? AUTHPARAM=1421409865_906DD11E2CABEF6E49C0A4E4B1A92B3A jdk-8u25-linux-x64.rpm

3. Install JDK:

RPM-IVH jdk-8u25-linux-x64.rpm

The default path for installation is/usr/java

You can then use the java,javac,java-version command to view the relevant information

4. Configure Environment variables

To edit a configuration file with Vim:

Vim/etc/profile

Press I into insert mode, append at end

Java_home=/usr/java/jdk1.8.0_25
Jre_home=/usr/java/jdk1.8.0_25/jre
Path= $PATH: $JAVA _home/bin: $JRE _home/bin
Classpath=.: $JAVA _home/lib/dt.jar: $JAVA _home/lib/tools.jar: $JRE _home/lib
Export Java_home jre_home PATH CLASSPATH

Press ESC to exit Insert mode, and then: Wq Save the changes and exit, and then use the following command to make the configuration effective:

Source/etc/profile

5. After this installation is configured, you can view path and java_home:

Echo $PATH

Echo $JAVA _home