在linux上使用yum安裝JDK

1.查找java相關得列表 [root@localhost ~]# yum -y list java* Loaded plugins: fastestmirror, refresh-packagekit, security Loading mirror speeds from cached hostfile

• base: mirrors.zju.edu.cn
• extras: mirrors.aliyun.com
• updates: mirrors.aliyun.com base | 3.7 kB 00:00
  extras | 3.4 kB 00:00
  updates | 3.4 kB 00:00
  Installed Packages java-1.5.0-gcj.x86_64 1.5.0.0-29.1.el6 @base/$releasever java-1.6.0-openjdk.x86_64 1:1.6.0.0-1.45.1.11.1.el6 @base/$releasever java_cup.x86_64 1:0.10k-5.el6 @base/$releasever Available Packages java-1.5.0-gcj-devel.x86_64 1.5.0.0-29.1.el6 base
  java-1.5.0-gcj-javadoc.x86_64 1.5.0.0-29.1.el6 base
  java-1.5.0-gcj-src.x86_64 1.5.0.0-29.1.el6 base
  java-1.6.0-openjdk.x86_64 1:1.6.0.35-1.13.7.1.el6_6 updates
  java-1.6.0-openjdk-demo.x86_64 1:1.6.0.35-1.13.7.1.el6_6 updates
  java-1.6.0-openjdk-devel.x86_64 1:1.6.0.35-1.13.7.1.el6_6 updates
  java-1.6.0-openjdk-javadoc.x86_64 1:1.6.0.35-1.13.7.1.el6_6 updates
  java-1.6.0-openjdk-src.x86_64 1:1.6.0.35-1.13.7.1.el6_6 updates
  java-1.7.0-openjdk.x86_64 1:1.7.0.79-2.5.5.1.el6_6 updates
  java-1.7.0-openjdk-demo.x86_64 1:1.7.0.79-2.5.5.1.el6_6 updates
  java-1.7.0-openjdk-devel.x86_64 1:1.7.0.79-2.5.5.1.el6_6 updates
  java-1.7.0-openjdk-javadoc.noarch 1:1.7.0.79-2.5.5.1.el6_6 updates
  java-1.7.0-openjdk-src.x86_64 1:1.7.0.79-2.5.5.1.el6_6 updates
  java-1.8.0-openjdk.x86_64 1:1.8.0.45-28.b13.el6_6 updates
  java-1.8.0-openjdk-demo.x86_64 1:1.8.0.45-28.b13.el6_6 updates
  java-1.8.0-openjdk-devel.x86_64 1:1.8.0.45-28.b13.el6_6 updates
  java-1.8.0-openjdk-headless.x86_64 1:1.8.0.45-28.b13.el6_6 updates
  java-1.8.0-openjdk-javadoc.noarch 1:1.8.0.45-28.b13.el6_6 updates
  java-1.8.0-openjdk-src.x86_64 1:1.8.0.45-28.b13.el6_6 updates
  java_cup-javadoc.x86_64 1:0.10k-5.el6 base
  java_cup-manual.x86_64 1:0.10k-5.el6 base
  javacc.x86_64 4.1-0.5.el6 base
  javacc-demo.x86_64 4.1-0.5.el6 base
  javacc-manual.x86_64 4.1-0.5.el6 base
  javassist.noarch 3.9.0-6.el6 base
  javassist-javadoc.noarch 3.9.0-6.el6 base

2.使用root用戶安裝 安裝時提醒必須使用root用戶，sudo都不行。 [root@localhost ~]# yum -y install java-1.7.0-openjdk* Loaded plugins: fastestmirror, refresh-packagekit, security Loading mirror speeds from cached hostfile

• base: mirrors.zju.edu.cn
• extras: mirrors.aliyun.com
• updates: mirrors.aliyun.com Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package java-1.7.0-openjdk.x86_64 1:1.7.0.79-2.5.5.1.el6_6 will be installed --> Processing Dependency: libjpeg.so.62(LIBJPEG_6.2)(64bit) for package: 1:java-1.7.0-openjdk-1.7.0.79-2.5.5.1.el6_6.x86_64 ---> Package java-1.7.0-openjdk-demo.x86_64 1:1.7.0.79-2.5.5.1.el6_6 will be installed ---> Package java-1.7.0-openjdk-devel.x86_64 1:1.7.0.79-2.5.5.1.el6_6 will be installed ---> Package java-1.7.0-openjdk-javadoc.noarch 1:1.7.0.79-2.5.5.1.el6_6 will be installed ---> Package java-1.7.0-openjdk-src.x86_64 1:1.7.0.79-2.5.5.1.el6_6 will be installed --> Running transaction check ---> Package libjpeg.x86_64 0:6b-46.el6 will be obsoleted ---> Package libjpeg-turbo.x86_64 0:1.2.1-3.el6_5 will be obsoleting --> Finished Dependency Resolution

Dependencies Resolved

================================================================================ Package Arch Version Repository Size

Installing: java-1.7.0-openjdk x86_64 1:1.7.0.79-2.5.5.1.el6_6 updates 26 M java-1.7.0-openjdk-demo x86_64 1:1.7.0.79-2.5.5.1.el6_6 updates 1.9 M java-1.7.0-openjdk-devel x86_64 1:1.7.0.79-2.5.5.1.el6_6 updates 9.4 M java-1.7.0-openjdk-javadoc noarch 1:1.7.0.79-2.5.5.1.el6_6 updates 16 M java-1.7.0-openjdk-src x86_64 1:1.7.0.79-2.5.5.1.el6_6 updates 39 M libjpeg-turbo x86_64 1.2.1-3.el6_5 base 174 k replacing libjpeg.x86_64 6b-46.el6

Transaction Summary

Install 6 Package(s)

Total download size: 92 M Downloading Packages: (1/6): java-1.7.0-openjdk-1.7.0.79-2.5.5.1.el6_6.x86_64. | 26 MB 02:44
(2/6): java-1.7.0-openjdk-demo-1.7.0.79-2.5.5.1.el6_6.x8 | 1.9 MB 00:10
(3/6): java-1.7.0-openjdk-devel-1.7.0.79-2.5.5.1.el6_6.x | 9.4 MB 01:23
(4/6): java-1.7.0-openjdk-javadoc-1.7.0.79-2.5.5.1.el6_6 | 16 MB 02:16
(5/6): java-1.7.0-openjdk-src-1.7.0.79-2.5.5.1.el6_6.x86 | 39 MB 04:23
(6/6): libjpeg-turbo-1.2.1-3.el6_5.x86_64.rpm | 174 kB 00:00

Total 143 kB/s | 92 MB 11:03
warning: rpmts_HdrFromFdno: Header V3 RSA/SHA1 Signature, key ID c105b9de: NOKEY Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6 Importing GPG key 0xC105B9DE: Userid : CentOS-6 Key (CentOS 6 Official Signing Key) centos-6-key@centos.org Package: centos-release-6-3.el6.centos.9.x86_64 (@base/$releasever) From : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6 Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Installing : libjpeg-turbo-1.2.1-3.el6_5.x86_64 1/7 Installing : 1:java-1.7.0-openjdk-1.7.0.79-2.5.5.1.el6_6.x86_64 2/7 Installing : 1:java-1.7.0-openjdk-src-1.7.0.79-2.5.5.1.el6_6.x86_64 3/7 Installing : 1:java-1.7.0-openjdk-demo-1.7.0.79-2.5.5.1.el6_6.x86_64 4/7 Installing : 1:java-1.7.0-openjdk-devel-1.7.0.79-2.5.5.1.el6_6.x86_64 5/7 Installing : 1:java-1.7.0-openjdk-javadoc-1.7.0.79-2.5.5.1.el6_6.noarch 6/7 Erasing : libjpeg-6b-46.el6.x86_64 7/7 Verifying : 1:java-1.7.0-openjdk-src-1.7.0.79-2.5.5.1.el6_6.x86_64 1/7 Verifying : 1:java-1.7.0-openjdk-1.7.0.79-2.5.5.1.el6_6.x86_64 2/7 Verifying : 1:java-1.7.0-openjdk-javadoc-1.7.0.79-2.5.5.1.el6_6.noarch 3/7 Verifying : 1:java-1.7.0-openjdk-demo-1.7.0.79-2.5.5.1.el6_6.x86_64 4/7 Verifying : 1:java-1.7.0-openjdk-devel-1.7.0.79-2.5.5.1.el6_6.x86_64 5/7 Verifying : libjpeg-turbo-1.2.1-3.el6_5.x86_64 6/7 Verifying : libjpeg-6b-46.el6.x86_64 7/7

Installed: java-1.7.0-openjdk.x86_64 1:1.7.0.79-2.5.5.1.el6_6
java-1.7.0-openjdk-demo.x86_64 1:1.7.0.79-2.5.5.1.el6_6
java-1.7.0-openjdk-devel.x86_64 1:1.7.0.79-2.5.5.1.el6_6
java-1.7.0-openjdk-javadoc.noarch 1:1.7.0.79-2.5.5.1.el6_6
java-1.7.0-openjdk-src.x86_64 1:1.7.0.79-2.5.5.1.el6_6
libjpeg-turbo.x86_64 0:1.2.1-3.el6_5

Replaced: libjpeg.x86_64 0:6b-46.el6

Complete!

3.確認是否安裝成功

[root@localhost ~]# java -version java version "1.7.0_79" OpenJDK Runtime Environment (rhel-2.5.5.1.el6_6-x86_64 u79-b14) OpenJDK 64-Bit Server VM (build 24.79-b02, mixed mode) [root@localhost ~]# 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 -d <directory> Specify where to place generated class files -s <directory> Specify where to place generated source 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 -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

[root@localhost ~]# java Usage: 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>
              require the specified version to run
-showversion  print product version and continue
-jre-restrict-search | -no-jre-restrict-search
              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 image

See http://www.oracle.com/technetwork/java/javase/documentation/index.html for more details.

4.默認狀況下jdk安裝得路徑 /usr/lib/jvm 因爲咱們得機器可能同時安裝好幾個版本得jdk，因此在/etc/alternatives目錄下會有一個java連接到具體的java命令。而這個/etc/alternatives/java會被/usr/bin/java連接。從而java命令就被設置到了shell環境中。