linux 安装 和 配置java

1.  download  jdk ：点击打开链接  如： jdk-7u45-linux-x64.rpm  

2. install jdk : rpm -ivh jdk-7u45-linux-x64.rpm

3. config jdk :

  # update-alternatives  --install  /usr/bin/java java /usr/java/jdk1.7.0_45/bin/java 1888
 
  # update-alternatives --config java
 
There are 3 programs which provide 'java'.
 
 Selection    Command
 
 
-----------------------------------------------
 
  1           /usr/lib/jvm/jre-1.6.0-openjdk.x86_64/bin/java  
 
* 2           /usr/lib/jvm/jre-1.7.0-openjdk.x86_64/bin/java
 
+ 3           /usr/java/jdk1.7.0_45/bin/java
 
Enter to keep the current selection[+], or type selection number: 3 
 
4. java -version to make sure install successfully.