CentOS JAVA安装及查看路径方法
CentOS JAVA安装及查看路径方法
2017-06-02 21:24
一、安装:
方法一:手动解压JDK的压缩包,然后设置环境变量
1.在/usr/目录下创建java目录
[root@localhost ~]# mkdir/usr/java
[root@localhost ~]# cd /usr/java
2.下载jdk,然后解压
[root@localhost java]# curl -O http://download.Oracle.com/otn-pub/java/jdk/7u79-b15/jdk-7u79-linux-x64.tar.gz
[root@localhost java]# tar -zxvf jdk-7u79-linux-x64.tar.gz
3.设置环境变量
[root@localhost java]# vi /etc/profile
在profile中添加如下内容:
#set java environment
JAVA_HOME=/usr/java/jdk1.7.0_79
JRE_HOME=/usr/java/jdk1.7.0_79/jre
CLASS_PATH=.:J
JAVA_HOME/lib/tools.jar:JPATH:J
JRE_HOME/bin
export JAVA_HOME JRE_HOME CLASS_PATH PATH
让修改生效:
[root@localhost java]# source /etc/profile
4.验证JDK有效性
[root@localhost java]# java -version
java version "1.7.0_79"
Java(TM) SE Runtime Environment (build 1.7.0_79-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.79-b02, mixed mode)
方法二:用yum安装JDK
1.查看yum库中都有哪些jdk版本(暂时只发现了openjdk)
[root@localhost ~]# yum search java|grep jdk
ldapjdk-javadoc.x86_64 : Javadoc for ldapjdk
java-1.6.0-openjdk.x86_64 : OpenJDK Runtime Environment
java-1.6.0-openjdk-demo.x86_64 : OpenJDK Demos
java-1.6.0-openjdk-devel.x86_64 : OpenJDK Development Environment
java-1.6.0-openjdk-javadoc.x86_64 : OpenJDK API Documentation
java-1.6.0-openjdk-src.x86_64 : OpenJDK Source Bundle
java-1.7.0-openjdk.x86_64 : OpenJDK Runtime Environment
java-1.7.0-openjdk-demo.x86_64 : OpenJDK Demos
java-1.7.0-openjdk-devel.x86_64 : OpenJDK Development Environment
java-1.7.0-openjdk-javadoc.noarch : OpenJDK API Documentation
java-1.7.0-openjdk-src.x86_64 : OpenJDK Source Bundle
java-1.8.0-openjdk.x86_64 : OpenJDK Runtime Environment
java-1.8.0-openjdk-demo.x86_64 : OpenJDK Demos
java-1.8.0-openjdk-devel.x86_64 : OpenJDK Development Environment
java-1.8.0-openjdk-headless.x86_64 : OpenJDK Runtime Environment
java-1.8.0-openjdk-javadoc.noarch : OpenJDK API Documentation
java-1.8.0-openjdk-src.x86_64 : OpenJDK Source Bundle
ldapjdk.x86_64 : The Mozilla LDAP Java SDK
2.选择版本,进行安装
//选择1.7版本进行安装
[root@localhost ~]# yum install java-1.7.0-openjdk
//安装完之后,默认的安装目录是在: /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.75.x86_64
3.设置环境变量
[root@localhost ~]# vi /etc/profile
在profile文件中添加如下内容
#set java environment
JAVA_HOME=/usr/lib/jvm/java-1.7.0-openjdk-1.7.0.75.x86_64
JRE_HOME=J
JAVA_HOME/lib/dt.jar:JJRE_HOME/lib
PATH=P
JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME JRE_HOME CLASS_PATH PATH
让修改生效
[root@localhost java]# source /etc/profile
4.验证(同上一方法)
方法三:用rpm安装JDK
1.下载rpm安装文件
[root@localhost ~]$ curl -O http://download.oracle.com/otn-pub/java/jdk/7u79-b15/jdk-7u79-linux-x64.rpm
2.使用rpm命令安装
[root@localhost ~]# rpm -ivh jdk-7u79-linux-x64.rpm
3.设置环境变量
[root@localhost java]# vi /etc/profile
在打开的profile文件中添加如下内容
#set java environment
JAVA_HOME=/usr/java/jdk1.7.0_79
JRE_HOME=/usr/java/jdk1.7.0_79/jre
CLASS_PATH=.:J
JAVA_HOME/lib/tools.jar:JPATH:J
JRE_HOME/bin
export JAVA_HOME JRE_HOME CLASS_PATH PATH
让修改生效
[root@localhost java]# source /etc/profile
4.验证(同上一方法)
注:和yum安装类似,不用设置环境变量就可以运行java命令。rpm安装方式默认会把jdk安装到/usr/java/jdk1.7.0_79,然后通过三层链接,链接到/usr/bin,具体链接如下:
[root@localhost ~]# cd /bin
[root@localhost bin]# ll|grep java
lrwxrwxrwx. 1 root root 25 Mar 28 11:24 jar ->/usr/java/default/bin/jar
lrwxrwxrwx. 1 root root 26 Mar 28 11:24 java -> /usr/java/default/bin/java
lrwxrwxrwx. 1 root root 27 Mar 28 11:24 javac ->/usr/java/default/bin/javac
lrwxrwxrwx. 1 root root 29 Mar 28 11:24 javadoc ->/usr/java/default/bin/javadoc
lrwxrwxrwx. 1 root root 28 Mar 28 11:24 javaws ->/usr/java/default/bin/javaws
lrwxrwxrwx. 1 root root 30 Mar 28 11:24 jcontrol ->/usr/java/default/bin/jcontrol
[root@localhost bin]# cd /usr/java/
[root@localhost java]# ll
total 4
lrwxrwxrwx. 1 root root 16 Mar 28 11:24 default-> /usr/java/latest
drwxr-xr-x. 8 root root 4096 Mar 28 11:24 jdk1.7.0_79
lrwxrwxrwx. 1 root root 21 Mar 28 11:24 latest -> /usr/java/jdk1.7.0_79
方法四:Ubuntu 上使用apt-get安装JDK
1.查看apt库都有哪些jdk版本
root@linuxidc:~# apt-cache search java|grep jdk
default-jdk - Standard Java or Java compatible Development Kit
default-jdk-doc - Standard Java or Java compatible Development Kit (documentation)
gcj-4.6-jdk - gcj and classpath development tools for Java(TM)
gcj-jdk - gcj and classpath development tools for Java(TM)
openjdk-6-dbg - Java runtime based on OpenJDK (debugging symbols)
openjdk-6-demo - Java runtime based on OpenJDK (demos and examples)
openjdk-6-doc - OpenJDK Development Kit (JDK) documentation
openjdk-6-jdk - OpenJDK Development Kit (JDK)
openjdk-6-jre-lib - OpenJDK Java runtime (architecture independent libraries)
openjdk-6-source - OpenJDK Development Kit (JDK) source files
openjdk-7-dbg - Java runtime based on OpenJDK (debugging symbols)
openjdk-7-demo - Java runtime based on OpenJDK (demos and examples)
openjdk-7-doc - OpenJDK Development Kit (JDK) documentation
openjdk-7-jdk - OpenJDK Development Kit (JDK)
openjdk-7-source - OpenJDK Development Kit (JDK) source files
uwsgi-plugin-jvm-openjdk-6 - Java plugin for uWSGI (OpenJDK 6)
uwsgi-plugin-jwsgi-openjdk-6 - JWSGI plugin for uWSGI (OpenJDK 6)
openjdk-6-jre - OpenJDK Java runtime, using Hotspot JIT
openjdk-6-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
openjdk-7-jre - OpenJDK Java runtime, using Hotspot JIT
openjdk-7-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
openjdk-7-jre-lib - OpenJDK Java runtime (architecture independent libraries)
2.选择版本进行安装
root@linuxidc:~# apt-get install openjdk-7-jdk
3.设置环境变量
root@linuxidc:~# vi /etc/profile
在打开的profile文件中添加如下内容
#set java environment
JAVA_HOME=/usr/lib/jvm/java-1.7.0-openjdk-amd64
JRE_HOME=J
JAVA_HOME/lib/dt.jar:JJRE_HOME/lib
PATH=P
JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME JRE_HOME CLASS_PATH PATH
让修改生效
root@linuxidc:~# source /etc/profile
4.验证(同上一方法)
二、查看安装路径:
总结一下如何查找JDK安装路径的方法
首先声明,echo J
JAVA_HOME配置错误,输出结果也是错误的。
其次,which java查询到的是java的执行路径,不是安装路径!!(以前我一直搞不清楚。。。面壁...)
再者,whereis java 也不能查询到安装路径,它就罗列出一堆包含java的文件,对查找安装路径一点用都没有!!!
最后,开始高潮部分:
![](https://upload-images.jianshu.io/upload_images/1243887-402e77ed2bdb9d9b.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
另附上/etc/profile配置详细格式,
![](https://upload-images.jianshu.io/upload_images/1243887-ced94ce500acd73a.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
然后,source /etc/profile 使之立即生效。
![](https://upload-images.jianshu.io/upload_images/1243887-3cfce45b1e13dcc5.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
在centos7的terminal中输入Java -verison是没问题的,但是javac的话就会提示没有此命令
百度了好久,说的很复杂,照着做了,最后也没有成功
后来在stackoverflow上看到了这个
84 down voteaccepted
|
You installed the Java Runtime Environment (JRE) only, which does not contain By the way: you can find out which package provides
Another note: using |
大意就是我们用yum来装原生的就行了
使用
yum install java-devel
就行了