redhat安装java

修改 vi /etc/profile，添加下面

export JAVA_HOME=/usr/java/jdk1.6.0_16
export PATH=$PATH:$JAVA_HOME/bin:$JAVA_HOME/jre/bin
export CLASSPATH=.:$JAVA_HOME/lib:$JAVA_HOME/jre/lib:$CLASSPATH
 

. /etc/profile

[root@rhtx java]# java -version
java version "1.4.2"
gij (GNU libgcj) version 4.1.2 20080704 (Red Hat 4.1.2-46)
 

[root@rhtx java]# javac -version
javac 1.6.0_16
 

就是没换过来，这里用这个方法解决：

[root@rhtx java]# update-alternatives --install  /usr/bin/java  java  /usr/java/jdk1.6.0_16/jre/bin/java   60
[root@rhtx java]# update-alternatives --config java

There are 2 programs which provide 'java'.

  Selection    Command
-----------------------------------------------
*+ 1           /usr/lib/jvm/jre-1.4.2-gcj/bin/java
   2           /usr/java/jdk1.6.0_16/jre/bin/java

Enter to keep the current selection[+], or type selection number: 2
[root@rhtx java]# java -version
java version "1.6.0_16"
Java(TM) SE Runtime Environment (build 1.6.0_16-b01)
Java HotSpot(TM) Server VM (build 14.2-b01, mixed mode)
 

或者，应该可以通过删除1.4的方法来解决：

[root@rhtx java]# rpm -qa|grep java
sun-javadb-docs-10.4.2-1.1
sun-javadb-core-10.4.2-1.1
java-1.4.2-gcj-compat-1.4.2.0-40jpp.115
sun-javadb-client-10.4.2-1.1
sun-javadb-demo-10.4.2-1.1
sun-javadb-common-10.4.2-1.1
sun-javadb-javadoc-10.4.2-1.1
 

把java-1.4.2 的删除了，可以解决。