Uninstalling and installing the JDK on Linux

1. Uninstall the default JDK:
Log in to the system with the root user and open a terminal input

#rpm-qa | grep GCJ

Display content contains the following two lines of information

                        # java-1.4.2-gcj-compat-1.4.2.0            # java-1.4.2-gcj-compat-devel-l.4.2.0

Start uninstalling the JDK

# rpm  -e  java-1.4.2-gcj-compat-1.4.2.0# rpm  -e  java-1.4.2-gcj-compat-devel-l.4.2.0

Uninstall any other JDK you have installed and use RPM-E java-xxxx directly

2. Install the JDK:
Download JDK installation files Jdk-6u10-linux-i586-rpm.bin
Upload the Jdk-6u10-linux-i586-rpm.bin to the Linux server and execute the following command under the shell

    #chmod  755  jdk-6u10-linux-i586-rpm.bin    #./jdk-6u10-linux-i586-rpm.bin

There will be a sun agreement, a few times the space bar, when asked whether or not to agree, knock Yes.
The program will automatically generate a jdk-6u10-linux-i586-rpm.rpm file, which is the main package, which is installed below:
#rpm-IVH jdk-6u10-linux-i586-rpm.rpm (installed by default in/usr/java)

3. Set environment variables (. bashrc files):
Modify the. bashrc file in the user's home directory to add the JDK environment variable.

    #vi  .bashrc    set JAVA_HOME=/usr/java/    export JAVA_HOME    set PATH=$PATH:$JAVA_HOME/bin    export PATH    set CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar    export CLASSPATH    #source  ./bashrc

This can also be done by changing the/etc/profile, but it is not recommended because such a setting will be effective for all users ' shells and will have an impact on system security. Here's a check to see if the variable setting is in effect (logout before verification and then re-login). If you want a user to have permission to run Java commands, simply modify their bash initialization file.

Environment variable configuration (/etc/profile file):
#vi/etc/profile
In the profile file, add the following:

    JAVA_HOME=/usr/java/jdk1.6.0_10    JRE_HOME=/usr/java/jdk1.6.0_10/jre    PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin    CLASSPATH=.:$JAVA_HOME/lib/jt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib    export JAVA_HOME JRE_HOME PATH CLASSPATH

Note: the preceding.: And Linux, Number: number.
Add Complete Save exit
#source/etc/profile

Uninstalling and installing the JDK on Linux