Centos7下安装与卸载Jdk1.8

卸载

[root@bogon jre]# rpm -qa|grep jdk
java-1.8.0-openjdk-headless-1.8.0.65-3.b17.el7.x86_64
java-1.7.0-openjdk-1.7.0.91-2.6.2.3.el7.x86_64
java-1.7.0-openjdk-headless-1.7.0.91-2.6.2.3.el7.x86_64
java-1.8.0-openjdk-1.8.0.65-3.b17.el7.x86_64

[root@bogon jre]# yum -y remove java-1.8.0-openjdk-headless-1.8.0.65-3.b17.el7.x86_64

[root@bogon lib]# java -version
bash: java: command not found...

安装

[root@bogon software]# tar -zxvf jdk-8u101-linux-x64.tar.gz -C /usr/local/java/

[root@bogon software]# vim /etc/profile
export JAVA_HOME=/usr/local/java/jdk1.8.0_101
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib
export PATH=${JAVA_HOME}/bin:$PATH

[root@bogon jdk1.8.0_101]# source /etc/profile

[root@bogon jdk1.8.0_101]# java -version
java version "1.8.0_101"
Java(TM) SE Runtime Environment (build 1.8.0_101-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.101-b13, mixed mode)
[root@bogon jdk1.8.0_101]# javac
Usage: javac <options> <source files>
where possible options include:
-g                         Generate all debugging info
-g:none                    Generate no debugging info
-g:{lines,vars,source}     Generate only some debugging info
-nowarn                    Generate no warnings
-verbose                   Output messages about what the compiler is doing
-deprecation               Output source locations where deprecated APIs are used
-classpath <path>          Specify where to find user class files and annotation processors
-cp <path>                 Specify where to find user class files and annotation processors
-sourcepath <path>         Specify where to find input source files
-bootclasspath <path>      Override location of bootstrap class files
-extdirs <dirs>            Override location of installed extensions
-endorseddirs <dirs>       Override location of endorsed standards path
-proc:{none,only}          Control whether annotation processing and/or compilation is done.
-processor <class1>[,<class2>,<class3>...] Names of the annotation processors to run; bypasses default discovery process
-processorpath <path>      Specify where to find annotation processors
-parameters                Generate metadata for reflection on method parameters
-d <directory>             Specify where to place generated class files
-s <directory>             Specify where to place generated source files
-h <directory>             Specify where to place generated native header files
-implicit:{none,class}     Specify whether or not to generate class files for implicitly referenced files
-encoding <encoding>       Specify character encoding used by source files
-source <release>          Provide source compatibility with specified release
-target <release>          Generate class files for specific VM version
-profile <profile>         Check that API used is available in the specified profile
-version                   Version information
-help                      Print a synopsis of standard options
-Akey[=value]              Options to pass to annotation processors
-X                         Print a synopsis of nonstandard options
-J<flag>                   Pass <flag> directly to the runtime system
-Werror                    Terminate compilation if warnings occur
@<filename>                Read options and filenames from file