SDKMAN：一款轻松管理多版本JDK的小工具

SDKMAN：是用于管理多个软件开发套件的并行版本的便捷工具。该工具对Java开发人员特别有用，因为它支持JVM的SDK，例如Java，Groovy，Scala，Kotlin和Ceylon。还支持Gradle，Maven，Spring Boot和许多其他工具。

安装步骤

下载脚本

[root@cx ~]# curl -s "https://get.sdkman.io" | bash

启动sdkman

[root@cx ~]# source "$HOME/.sdkman/bin/sdkman-init.sh"

至此安装完毕，超级简单。

使用方式

list命令

list命令会列出指定选项的所有可选版本。

[root@cx ~]# sdk list java
================================================================================
Available Java Versions
================================================================================
 Vendor        | Use | Version      | Dist    | Status     | Identifier
--------------------------------------------------------------------------------
 AdoptOpenJDK  |     | 13.0.2.j9    | adpt    |            | 13.0.2.j9-adpt            
 Java.net      |     | 15.ea.14     | open    |            | 15.ea.14-open       
               |     | 14.0.0       | open    |            | 14.0.0-open         
               |     | 12.0.2       | open    |            | 12.0.2-open         
               |     | 11.0.6       | open    |            | 11.0.6-open         
               |     | 10.0.2       | open    |            | 10.0.2-open         
               |     | 9.0.4        | open    |            | 9.0.4-open          
               |     | 8.0.242      | open    |            | 8.0.242-open        
 SAP           |     | 13.0.2       | sapmchn |            | 13.0.2-sapmchn      
               |     | 12.0.2       | sapmchn |            | 12.0.2-sapmchn      
               |     | 11.0.6       | sapmchn |            | 11.0.6-sapmchn      
================================================================================
Use the Identifier for installation:

    $ sdk install java 11.0.3.hs-adpt
================================================================================

install命令

install命令会执行安装版本sdk

[root@cx ~]# sdk install java 11.0.3.hs-adpt

默认安装位置在~/.sdkman/candidates/java/目录下：

[root@cx ~]#  ls -al ~/.sdkman/candidates/java/
drwxr-xr-x  6 root root  288 3月 1 12:02 12.0.2-open
drwxr-xr-x  6 root root  288 3月 1 12:05 13.0.1-open
lrwxrwxrwx  1 root root   57 3月 1 12:02 current -> /root/.sdkman/candidates/java/13.0.1-open

default 命令

使用default切换默认运行版本：

[root@cx ~]#  java -version
openjdk version "13.0.1" 2019-10-15
OpenJDK Runtime Environment (build 13.0.1+9)
OpenJDK 64-Bit Server VM (build 13.0.1+9, mixed mode, sharing)

[root@cx ~]#  ls -al ~/.sdkman/candidates/java/
drwxr-xr-x  6 root root  288 3月 1 12:02 12.0.2-open
drwxr-xr-x  6 root root  288 3月 1 12:05 13.0.1-open
lrwxrwxrwx  1 root root   57 3月 1 12:02 current -> /root/.sdkman/candidates/java/13.0.1-open

[root@cx ~]#  sdk default java 12.0.2-open
Default java version set to 12.0.2-open

[root@cx ~]#  java -version
openjdk version "12.0.2" 2019-07-16
OpenJDK Runtime Environment (build 12.0.2+10)
OpenJDK 64-Bit Server VM (build 12.0.2+10, mixed mode, sharing)

[root@cx ~]#  ls -al ~/.sdkman/candidates/java/
drwxr-xr-x  6 root root  288 3月 1 12:02 12.0.2-open
drwxr-xr-x  6 root root  288 3月 1 12:05 13.0.1-open
lrwxrwxrwx  1 root root   57 3月 1 12:02 current -> /root//.sdkman/candidates/java/12.0.2-open

其他安装

Maven

直接使用sdk instlal maven 会默认安装最新版

[root@cx ~]#  sdk install maven
Downloading: maven 3.6.3
In progress... 100.0%
Installing: maven 3.6.3
Done installing!

Setting maven 3.6.3 as default.
# sdk list maven
================================================================================
Available Maven Versions
================================================================================
 > * 3.6.3                                                                      
     3.6.2                                                                      
     3.6.1                                                                      
     3.6.0                                                                      
     3.5.4                                                                      
     3.5.3                                                                      
     3.5.2                                                                      
     3.5.0                                                                      
     3.3.9                                                                      
                                                                                
                                                                             
================================================================================
+ - local version
* - installed
> - currently in use
================================================================================

安装Gradle

安装和Maven同理，可直接安装最新版，也可指定版本号。

sdk install gradle

其他

方式都是如出一辙，感兴趣可以自行尝试。