Redhat 安装JDK

1.检查是否有旧版本的jdk

[root@localhost soft]# java -version
java version "1.4.2"
gij (GNU libgcj) version 4.1.2 20080704 (Red Hat 4.1.2-48)

Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

[root@localhost soft]# rpm -qa|grep gcj
libgcj-4.1.2-48.el5
java-1.4.2-gcj-compat-1.4.2.0-40jpp.115
libgcj-4.1.2-48.el5

2.卸载旧的jdk

[root@localhost soft]# rpm -e --nodeps java-1.4.2-gcj-compat-1.4.2.0-40jpp.115

[root@localhost soft]# java -version
-bash: /usr/bin/java: 没有那个文件或目录

3.后安装新的jdk

./ jdk-1_5_0_15-linux-i586.bin
mkdir /usr/java
mv jdk1.5.0_15 /usr/java/

ln -s /usr/java/jdk1.5.0_16/bin/java /usr/bin/java

ln -s /usr/java/jdk1.5.0_16/bin/javac /usr/bin/javac

4.编写环境变量:

在/etc/profile里写入如下:

#vi /etc/profile
JAVA_HOME=/usr/java/jdk1.5.0_16
JRE_HOME=/usr/java/jdk1.5.0_16/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
export LANG=zh_CN.gb18030

5.使环境变量生效:

#source /etc/profile