CentOS Install JDK correctly

1 "First find out the Java default installation under CentOS

Whereis Java
Which Java (Java run path)
Echo $JAVA _home

Echo $PATH

2> View and Uninstall:

See if there is a Java-used command: RPM-QA | grep java

Some words delete: pm-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

See if JDK Rpm-qa | grep JDK

Some words Delete:

[Email protected] usr]# Rpm-qa | grep JDK
jdk-1.7.0_02-fcs.i586
[Email protected] usr]# rpm-e--nodeps jdk-1.7.0_02-fcs.i586

View No Rpm-qa | grep GCJ

3 "Installation

RPM-IVH jdk-7u2-linux-i586.rpm

After the installation will be under/usr/to extract a Java directory, the directory has a jdk1.7.0_02

4 "Configuration

Join Vi/etc/profile

Export java_home=/usr/java/jdk1.7.0_02
Export classpath=.: $JAVA _home/jre/lib/rt.jar: $JAVA _home/lib/dt.jar: $JAVA _home/lib/tools.jar
Export path= $PATH: $JAVA _home/bin

5 "Test

[Email protected] javacode]# Javac Test.java
[[Email protected] javacode]# java test
Hello!

CentOS Install JDK correctly