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1.更新源

sudo apt update

2.升級

sudo apt upgrade -y

3.查看jdk版本

sudo apt-cache search jdk

部分內容顯示如下

default-jdk - Standard Java or Java compatible Development Kit
default-jdk-doc - Standard Java or Java compatible Development Kit (documentation)
openjdk-11-jre-dcevm - Alternative VM for OpenJDK 11 with enhanced class 
...
openjdk-17-jre-zero - Alternative JVM for OpenJDK, using Zero
openjdk-17-source - OpenJDK Development Kit (JDK) source files
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-jre - OpenJDK Java runtime, using Hotspot JIT
openjdk-8-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
openjdk-8-jre-zero - Alternative JVM for OpenJDK, using Zero/Shark
openjdk-8-source - OpenJDK Development Kit (JDK) source files
substance - cross-platform look & feel for Swing applications
substance-doc - cross-platform look & feel for Swing applications - documentation
substance-flamingo - Substance Flamingo plugin
...

4.選擇需要安裝的版本進行安裝，以安裝jdk-8爲例

安裝目錄爲 /usr/lib/jvm

sudo apt install -y openjdk-8-jdk

5.查看java版本

java -version

6.切換不同版本的java

• 通過軟鏈接切換j不同的版本-java

sudo update-alternatives --config java

我的系統顯示如下：

There are 3 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                            Priority   Status
------------------------------------------------------------
  0            /usr/lib/jvm/java-18-openjdk-amd64/bin/java      1811      auto mode
  1            /usr/lib/jvm/java-11-openjdk-amd64/bin/java      1111      manual mode
  2            /usr/lib/jvm/java-18-openjdk-amd64/bin/java      1811      manual mode
* 3            /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java   1081      manual mode

Press <enter> to keep the current choice[*], or type selection number: 

根據提示鍵入需要的jdk版本。

• 通過軟鏈接切換不同的版本-javac

sudo update-alternatives --config javac

參考：

Ubuntu 系统安装多个版本的 JDK – 简书