1.查看CentOS自带JDK是否已安装. yum list installed |grep java. 2.卸载原有JDK yum -y remove java-1.5.0-gcj.i686 3.查看yum库中的JDK包 yum -y list java* 4.安装JDK yum -y install java--openjdk.i686 [root@VM_238_215_centos ~]# yum list installed |grep java java--gcj.i686 1.5.0