CentOS under JDK Installation

First step: Check if the Linux-brought JDK is installed (uninstall CentOS installed 1.4)

The installed CentOS will bring openjdk, with the command java-version, will have the following information:

Java Version "1.6.0"
OpenJDK Runtime Environment (build 1.6.0-b09)
OpenJDK 64-bit Server VM (build 1.6.0-b09, Mixed mode)

It is best to uninstall the OPENJDK before installing Sun's JDK.

See Rpm-qa First | grep java

The following information is displayed:

java-1.4.2-gcj-compat-1.4.2.0-40jpp.115
Java-1.6.0-openjdk-1.6.0.0-1.7.b09.el5

Unloading:

RPM-E--nodeps java-1.4.2-gcj-compat-1.4.2.0-40jpp.115
RPM-E--nodeps Java-1.6.0-openjdk-1.6.0.0-1.7.b09.el5

There are some other commands.

Rpm-qa | grep GCJ

Rpm-qa | grep JDK

If OpenJDK source cannot be found, you can also uninstall this

Yum-y Remove Java java-1.4.2-gcj-compat-1.4.2.0-40jpp.115
Yum-y Remove Java Java-1.6.0-openjdk-1.6.0.0-1.7.b09.el5

<1># rpm-qa|grep jdk← View JDK information or execute directly
Or
# rpm-q JDK
Or
# java-version
<2># Rpm-qa | grep gcj← Confirm version number of GCJ
<3># yum-y Remove java-1.4.2-gcj-compat← Uninstall GCJ

Step Two: Install the JDK
<1> download Jdk-1_5_0_14-linux-i586-rpm.bin or Jdk-1_5_0_14-linux-i586.bin from Sun
Create a new Java folder under/usr and place the installation package in the/usr/java directory
# Mkdir/usr/java
<2> Installing the JDK
# Cd/usr/java
①jdk-1_5_0_14-linux-i586-rpm.bin File Installation
# chmod 777 jdk-1_5_0_14-linux-i586-rpm.bin← modified to executable
#./jdk-1_5_0_14-linux-i586-rpm.bin← Select Yes to agree to the above agreement
# RPM-IVH jdk-1_5_0_14-linux-i586.rpm← Select Yes until installation is complete
②jdk-1_5_0_14-linux-i586.bin File Installation
# chmod a+x jdk-1_5_0_14-linux-i586.bin← enables the current user to have Execute permissions
#./jdk-1_5_0_14-linux-i586.bin← Select Yes until installation is complete

Step Three: Configure environment variables
<1># Vi/etc/profile
<2> Add the following lines at the end:
Export JAVA_HOME=/USR/JAVA/JDK1.6.0_10
Export classpath=.: $JAVA _home/jre/lib/rt.jar: $JAVA _home/lib/dt.jar: $JAVA _home/lib/tools.jar
Export path= $PATH: $JAVA _home/bin
<3># reboot← Restart machine configuration effective

CentOS under JDK Installation