CentOS7 安装JDK1.8

安装准备

• Operating System: CentOS7.0
• Installation: RPM package
• Software: jdk-8u77-linux-x64.rpm

查看现有JDK版本

# check the current jdk version[dtadmin@~]$ java -version# check the current jdk details[dtadmin@~]$ sudo rpm -qa | grep java

卸载自带openJDK

[dtadmin@~]$ sudo rpm -e --nodeps tzdata-java-1.8.0-openjdk[dtadmin@~]$ sudo rpm -e --nodeps java-1.8.0-openjdk-headless[dtadmin@~]$ sudo rpm -e --nodeps java-1.8.0-openjdk

rpm安装 JDK 1.8

[dtadmin@apollo ~]$ sudo rpm -ivh jdk-8u77-linux-x64.rpmWe trust you have received the usual lecture from the local SystemAdministrator. It usually boils down to these three things:    #1) Respect the privacy of others.    #2) Think before you type.    #3) With great power comes great responsibility.[sudo] password for dtadmin:Preparing...                          ################################# [100%]Updating / installing...   1:jdk1.8.0_77-2000:1.8.0_77-fcs    ################################# [100%]Unpacking JAR files...    tools.jar...    plugin.jar...    javaws.jar...    deploy.jar...    rt.jar...    jsse.jar...    charsets.jar...    localedata.jar...    jfxrt.jar...

验证JDK1.8

[dtadmin@apollo ~]$ javaUsage: java [-options] class [args...]           (to execute a class)   or  java [-options] -jar jarfile [args...]           (to execute a jar file)where options include:    -d32      use a 32-bit data model if available    -d64      use a 64-bit data model if available    -server   to select the "server" VM                  The default VM is server.    -cp <class search path of directories and zip/jar files>    -classpath <class search path of directories and zip/jar files>                  A : separated list of directories, JAR archives,                  and ZIP archives to search for class files.    -D<name>=<value>                  set a system property    -verbose:[class|gc|jni]                  enable verbose output    -version      print product version and exit    -version:<value>                  Warning: this feature is deprecated and will be removed                  in a future release.                  require the specified version to run    -showversion  print product version and continue    -jre-restrict-search | -no-jre-restrict-search                  Warning: this feature is deprecated and will be removed                  in a future release.                  include/exclude user private JREs in the version search    -? -help      print this help message    -X            print help on non-standard options    -ea[:<packagename>...|:<classname>]    -enableassertions[:<packagename>...|:<classname>]                  enable assertions with specified granularity    -da[:<packagename>...|:<classname>]    -disableassertions[:<packagename>...|:<classname>]                  disable assertions with specified granularity    -esa | -enablesystemassertions                  enable system assertions    -dsa | -disablesystemassertions                  disable system assertions    -agentlib:<libname>[=<options>]                  load native agent library <libname>, e.g. -agentlib:hprof                  see also, -agentlib:jdwp=help and -agentlib:hprof=help    -agentpath:<pathname>[=<options>]                  load native agent library by full pathname    -javaagent:<jarpath>[=<options>]                  load Java programming language agent, see java.lang.instrument    -splash:<imagepath>                  show splash screen with specified imageSee http://www.oracle.com/technetwork/java/javase/documentation/index.html for more details.[dtadmin@apollo ~]$ javacUsage: 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[dtadmin@apollo ~]$ java -versionjava version "1.8.0_77"Java(TM) SE Runtime Environment (build 1.8.0_77-b03)Java HotSpot(TM) 64-Bit Server VM (build 25.77-b03, mixed mode)

JDK环境变量设置

# set the jdk environment variables /etc/profile[root@apollo jdk1.8.0_77]# sudo echo '#JDK1.8 configuration' >> /etc/profile[root@apollo jdk1.8.0_77]# echo 'JAVA_HOME=/usr/java/jdk1.8.0_77' >> /etc/profile[root@apollo jdk1.8.0_77]# echo "JRE_HOME=\$JAVA_HOME/jre" >> /etc/profile[root@apollo jdk1.8.0_77]# echo "PATH=\$PATH:\$JAVA_HOME/bin:\$JRE_HOME/bin" >> /etc/profile[root@apollo jdk1.8.0_77]# echo "CLASSPATH=.:\$JAVA_HOME/lib/dt.jar:\$JAVA_HOME/lib/tools.jar:\$JRE_HOME/lib" >> /etc/profile[root@apollo jdk1.8.0_77]# echo "export JAVA_HOME JRE_HOME PATH CLASSPATH" >> /etc/profile# check the environment variables setting[root@apollo jdk1.8.0_77]# tail -6 /etc/profile#JDK1.8 configurationJAVA_HOME=/usr/java/jdk1.8.0_77JRE_HOME=$JAVA_HOME/jrePATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/binCLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/libexport JAVA_HOME JRE_HOME PATH CLASSPATH# 使环境变量生效[dtadmin@apollo jdk1.8.0_77]$ source /etc/profile[root@apollo jdk1.8.0_77]# echo $PATH/usr/local/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/home/dtadmin/.local/bin:/home/dtadmin/bin:/bin:/bin:/usr/java/jdk1.8.0_77/bin:/usr/java/jdk1.8.0_77/jre/bin