Linux 下面jdk 安装
一：查看原来的jdk安装路径
[root@li1062-188 bin]# which java /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.101.x86_64/bin/java [root@li1062-188 bin]#which java 是查看java的执行路径
二：卸载旧版本的jdk版本
1：查找jdk的版本在哪个路径
[root@li1062-188 bin]# rpm -qa | grep jdk java-1.7.0-openjdk-1.7.0.101-2.6.6.1.el6_7.x86_64 java-1.7.0-openjdk-devel-1.7.0.101-2.6.6.1.el6_7.x86_64 [root@li1062-188 bin]# rpm -qa | grep gcj (这个难道是垃圾加收机制吗） libgcj-4.4.7-16.el6.x86_64
2：卸载jdk
[root@li1062-188 bin]# yum -y remove java-1.7.0-openjdk-1.7.0.101-2.6.6.1.el6_7.x86_64 Loaded plugins: fastestmirror Setting up Remove Process Resolving Dependencies --> Running transaction check ---> Package java-1.7.0-openjdk.x86_64 1:1.7.0.101-2.6.6.1.el6_7 will be erased --> Processing Dependency: java-1.7.0-openjdk = 1:1.7.0.101-2.6.6.1.el6_7 for package: 1:java-1.7.0-openjdk-devel-1.7.0.101-2.6.6.1.el6_7.x86_64 --> Running transaction check ---> Package java-1.7.0-openjdk-devel.x86_64 1:1.7.0.101-2.6.6.1.el6_7 will be erased --> Finished Dependency Resolution Dependencies Resolved ============================================================================================================================================================================================================================================ Package Arch Version Repository Size ============================================================================================================================================================================================================================================ Removing: java-1.7.0-openjdk x86_64 1:1.7.0.101-2.6.6.1.el6_7 @updates 91 M Removing for dependencies: java-1.7.0-openjdk-devel x86_64 1:1.7.0.101-2.6.6.1.el6_7 @updates 36 M Transaction Summary ============================================================================================================================================================================================================================================ Remove 2 Package(s) Installed size: 127 M Downloading Packages: Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Erasing : 1:java-1.7.0-openjdk-1.7.0.101-2.6.6.1.el6_7.x86_64 1/2 Erasing : 1:java-1.7.0-openjdk-devel-1.7.0.101-2.6.6.1.el6_7.x86_64 2/2 Verifying : 1:java-1.7.0-openjdk-devel-1.7.0.101-2.6.6.1.el6_7.x86_64 1/2 Verifying : 1:java-1.7.0-openjdk-1.7.0.101-2.6.6.1.el6_7.x86_64 2/2 Removed: java-1.7.0-openjdk.x86_64 1:1.7.0.101-2.6.6.1.el6_7 Dependency Removed: java-1.7.0-openjdk-devel.x86_64 1:1.7.0.101-2.6.6.1.el6_7 Complete! [root@li1062-188 bin]# yum -y remove java-1.7.0-openjdk-devel-1.7.0.101-2.6.6.1.el6_7.x86_64 Loaded plugins: fastestmirror Setting up Remove Process No Match for argument: java-1.7.0-openjdk-devel-1.7.0.101-2.6.6.1.el6_7.x86_64 Loading mirror speeds from cached hostfile * base: mirrors.linode.com * extras: mirrors.linode.com * updates: mirrors.linode.com Package(s) java-1.7.0-openjdk-devel-1.7.0.101-2.6.6.1.el6_7.x86_64 available, but not installed. No Packages marked for removal [root@li1062-188 bin]# rpm -qa | grep jdk [root@li1062-188 bin]#
[root@li1062-188 bin]# rpm -qa | grep gcj libgcj-4.4.7-16.el6.x86_64 [root@li1062-188 bin]# yum -y remove libgcj-4.4.7-16.el6.x86_64 Loaded plugins: fastestmirror Setting up Remove Process Resolving Dependencies --> Running transaction check ---> Package libgcj.x86_64 0:4.4.7-16.el6 will be erased --> Finished Dependency Resolution Dependencies Resolved ============================================================================================================================================================================================================================================ Package Arch Version Repository Size ============================================================================================================================================================================================================================================ Removing: libgcj x86_64 4.4.7-16.el6 @base 62 M Transaction Summary ============================================================================================================================================================================================================================================ Remove 1 Package(s) Installed size: 62 M Downloading Packages: Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Erasing : libgcj-4.4.7-16.el6.x86_64 1/1 warning: /usr/lib64/security/classpath.security saved as /usr/lib64/security/classpath.security.rpmsave Verifying : libgcj-4.4.7-16.el6.x86_64 1/1 Removed: libgcj.x86_64 0:4.4.7-16.el6 Complete!
3.查看 /etc/profile 里面有没有配置java_home，安装完成之后，可以查看CLASSPATH,PATH等路径
[root@li1062-188 bin]# echo $JAVA_HOME /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.101.x86_64
以上，就卸载掉了jdk
三：下载新的jdk文件，一是通过wget 方式，一是通过yum install jdk 的方式，当不知道wget的路径时候，我们采用第二种方法。
1：查看有哪些可以安装的jdk
[root@li1062-188 bin]# yum -y list java* Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirrors.linode.com * extras: mirrors.linode.com * updates: mirrors.linode.com Available Packages java-1.5.0-gcj.x86_64 1.5.0.0-29.1.el6 base 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 1:1.6.0.38-1.13.10.0.el6_7 updates java-1.6.0-openjdk-demo.x86_64 1:1.6.0.38-1.13.10.0.el6_7 updates java-1.6.0-openjdk-devel.x86_64 1:1.6.0.38-1.13.10.0.el6_7 updates java-1.6.0-openjdk-javadoc.x86_64 1:1.6.0.38-1.13.10.0.el6_7 updates java-1.6.0-openjdk-src.x86_64 1:1.6.0.38-1.13.10.0.el6_7 updates java-1.7.0-openjdk.x86_64 1:1.7.0.101-2.6.6.1.el6_7 updates java-1.7.0-openjdk-demo.x86_64 1:1.7.0.101-2.6.6.1.el6_7 updates java-1.7.0-openjdk-devel.x86_64 1:1.7.0.101-2.6.6.1.el6_7 updates java-1.7.0-openjdk-javadoc.noarch 1:1.7.0.101-2.6.6.1.el6_7 updates java-1.7.0-openjdk-src.x86_64 1:1.7.0.101-2.6.6.1.el6_7 updates java-1.8.0-openjdk.x86_64 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-debug.x86_64 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-demo.x86_64 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-demo-debug.x86_64 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-devel.x86_64 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-devel-debug.x86_64 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-headless.x86_64 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-headless-debug.x86_64 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-javadoc.noarch 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-javadoc-debug.noarch 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-src.x86_64 1:1.8.0.91-0.b14.el6_7 updates java-1.8.0-openjdk-src-debug.x86_64 1:1.8.0.91-0.b14.el6_7 updates java_cup.x86_64 1:0.10k-5.el6 base 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
2:下载并安装jdk1.7，注意我们需要下载两个文件，java-1.7.0-openjdk.x86_64 只有jre
<pre name="code" class="plain">java-1.7.0-openjdk-devel.x86_64
[root@li1062-188 bin]# yum -y install java-1.7.0-openjdk.x86_64 Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirrors.linode.com * extras: mirrors.linode.com * updates: mirrors.linode.com Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package java-1.7.0-openjdk.x86_64 1:1.7.0.101-2.6.6.1.el6_7 will be installed --> Finished Dependency Resolution Dependencies Resolved ============================================================================================================================================================================================================================================ Package Arch Version Repository Size ============================================================================================================================================================================================================================================ Installing: java-1.7.0-openjdk x86_64 1:1.7.0.101-2.6.6.1.el6_7 updates 26 M Transaction Summary ============================================================================================================================================================================================================================================ Install 1 Package(s) Total download size: 26 M Installed size: 91 M Downloading Packages: java-1.7.0-openjdk-1.7.0.101-2.6.6.1.el6_7.x86_64.rpm | 26 MB 00:00 Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Installing : 1:java-1.7.0-openjdk-1.7.0.101-2.6.6.1.el6_7.x86_64 1/1 Verifying : 1:java-1.7.0-openjdk-1.7.0.101-2.6.6.1.el6_7.x86_64 1/1 Installed: java-1.7.0-openjdk.x86_64 1:1.7.0.101-2.6.6.1.el6_7 Complete!
[root@li1062-188 bin]# yum -y install java-1.7.0-openjdk-devel.x86_64 Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirrors.linode.com * extras: mirrors.linode.com * updates: mirrors.linode.com Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package java-1.7.0-openjdk-devel.x86_64 1:1.7.0.101-2.6.6.1.el6_7 will be installed --> Finished Dependency Resolution Dependencies Resolved ============================================================================================================================================================================================================================================ Package Arch Version Repository Size ============================================================================================================================================================================================================================================ Installing: java-1.7.0-openjdk-devel x86_64 1:1.7.0.101-2.6.6.1.el6_7 updates 9.4 M Transaction Summary ============================================================================================================================================================================================================================================ Install 1 Package(s) Total download size: 9.4 M Installed size: 36 M Downloading Packages: java-1.7.0-openjdk-devel-1.7.0.101-2.6.6.1.el6_7.x86_64.rpm | 9.4 MB 00:00 Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Installing : 1:java-1.7.0-openjdk-devel-1.7.0.101-2.6.6.1.el6_7.x86_64 1/1 Verifying : 1:java-1.7.0-openjdk-devel-1.7.0.101-2.6.6.1.el6_7.x86_64 1/1 Installed: java-1.7.0-openjdk-devel.x86_64 1:1.7.0.101-2.6.6.1.el6_7 Complete!
3：查看jdk 是否安装OK
[root@li1062-188 bin]# 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.
[root@li1062-188 bin]# java -version
java version "1.7.0_101"
OpenJDK Runtime Environment (rhel-2.6.6.1.el6_7-x86_64 u101-b00)
OpenJDK 64-Bit Server VM (build 24.95-b01, mixed mode)
四：配置jdk的环境变量
1：找到java的安装路径
[root@li1062-188 bin]# cd / [root@li1062-188 /]# find -name java ./var/lib/alternatives/java ./etc/pki/ca-trust/extracted/java ./etc/pki/java ./etc/alternatives/java ./etc/java ./usr/share/java ./usr/bin/java ./usr/lib/jvm-exports/java ./usr/lib/jvm/java-1.7.0-openjdk-1.7.0.101.x86_64/jre/bin/java ./usr/lib/jvm/java-1.7.0-openjdk-1.7.0.101.x86_64/bin/java ./usr/lib/jvm/java ./usr/lib/java或者
[root@li1062-188 /]# which java /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.101.x86_64/bin/java [root@li1062-188 /]#
2：在/etc/profile 中配置jdk环境变量
[root@li1062-188 /]# vi /etc/profile
export JAVA_HOME=/usr/lib/jvm/java-1.7.0-openjdk-1.7.0.101.x86_64 export CLASSPATH=$CLASSPATH:$JAVA_HOME/lib:$JAVA_HOME/jre/lib export PATH=$JAVA_HOME/bin:$JAVA_HOME/jre/bin:$PATH:$HOME/bin