ubuntu/linux下命令行安装jdk

1.ubuntu使用的是openjdk，所以我们需要先找到合适的jdk版本。在命令行中输入命令：

$apt-cache search openjdk

返回结果列表(因个人电脑而有所不同)：

default-jdk-doc - Standard Java or Java compatible Development Kit (documentation)

…(省略部分显示结果)

openjdk-6-source - OpenJDK Development Kit (JDK) source files

openjdk-7-jre-dcevm - Alternative VM for OpenJDK 7 with enhanced class redefinition

openjdk-7-jre-lib - OpenJDK Java runtime (architecture independent libraries)

openjdk-7-jre-zero - Alternative JVM for OpenJDK, using Zero/Shark

openjdk-8-dbg - Java runtime based on OpenJDK (debugging symbols)

openjdk-8-demo - Java runtime based on OpenJDK (demos and examples)

openjdk-8-doc - OpenJDK Development Kit (JDK) documentation

openjdk-8-jdk - OpenJDK Development Kit (JDK)

openjdk-8-jre - OpenJDK Java runtime, using Hotspot JIT

openjdk-8-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)

openjdk-8-jre-jamvm - Alternative JVM for OpenJDK, using JamVM

openjdk-8-jre-zero - Alternative JVM for OpenJDK, using Zero/Shark

openjdk-8-source - OpenJDK Development Kit (JDK) source files

uwsgi-app-integration-plugins - plugins for integration of uWSGI and application

uwsgi-plugin-jvm-openjdk-7 - Java plugin for uWSGI (OpenJDK 7)

2.从搜索的列表里找到我们需要安装的jdk版本，如上面标黑的

openjdk-8-jdk - OpenJDK Development Kit (JDK)

3.输入安装命令，进行安装：

$sudo apt-get install openjdk-8-jdk

等待命令行显示“done”，即安装成功过。

4.查看安装结果。输入命令：

$java -version

显示结果如下：

openjdk version “1.8.0_91”

OpenJDK Runtime Environment (build 1.8.0_91-8u91-b14-0ubuntu4~15.10.1-b14)

OpenJDK Server VM (build 25.91-b14, mixed mode)

则说明安装成功。

5.安装成功后，还需要配置java_home变量：

1)输入命令：echo $java_home

返回空行；

2）which javac

返回：/usr/bin/javac

3）file /usr/bin/javac

返回：/usr/bin/javac: symbolic link to /etc/alternatives/javac

4）file /etc/alternatives/javac

返回：/etc/alternatives/javac: symbolic link to /usr/lib/jvm/java-8-openjdk-i386/bin/javac

5）file /usr/lib/jvm/java-8-openjdk-i386/bin/javac

返回：/usr/lib/jvm/java-8-openjdk-i386/bin/javac: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=a8eeb948df0418fc8f046910c73713f2b6697a9a, stripped

6）sudo echo export JAVA_HOME=”/usr/lib/jvm/java-8-openjdk-i386/bin”>>~/.bashrc

输入密码；

7）source ~/.bashrc

8）测试命令：gedit ~/.bashrc

查看打开的文件末尾是否成功加入java_home