最好是安装默认Java，直到不需要特定的Java版本。 在此之前，执行java -version检查java是否尚未安装。

sudo apt-get update  
sudo apt-get install default-jre  
sudo apt-get install default-jdk

这就是安装Java所需的一切。

你可以使用SDKMan，

curl -s "https://get.sdkman.io" | bash
source "~/.sdkman/bin/sdkman-init.sh"
sdk install java

OpenJDK在大多数情况下是可以的，但对于一些银行客户端应用程序(我的情况)可能需要Oracle JDK -我不能使用OpenJDK。

我很惊讶，在Ubuntu 12.10+的Oracle JDK中，我没有看到任何默认方法(没有外部PPAs的存储库)的答案-我会尝试描述它。

安装JavaPackage: Sudo apt-get安装java-package 从Oracle下载页面下载Oracle JDK 从下载的.tar.gz文件中制作一个Debian包: make-jpkg jdk-YOUR_VERSION-linux-PLATFORM.tar.gz 这个命令将生成一个.deb包。 以您喜欢的方式安装包(例如，sudo dpkg -i oracle-java8-jdk_8u40_amd64.deb)

这是Debian开发人员官方支持的安装Oracle JDK的方法，我认为它非常简单。

我只是在Ubuntu虚拟机上做了这个。我是这样做的。

Ubuntu comes with the Java JRE installed, but not the JDK. Java -version gives the JRE, not the JDK. Run javac -version. If the JDK isn't installed, you will get an error. Run the following command in the terminal to get the JDK: sudo apt install default-jdk. Now, run which javac. The output should be /usr/bin/javac. It has now been installed. IntelliJ won't let us use this path because it is the binary of javac. Go to Project Structure > Project Settings > Project. Where it says 'Project SDK', add a JDK. Then go to /usr/lib/jvm. Now you should be able to compile java projects in IntellIJ.

您可能必须编辑配置，以便IntelliJ知道在哪里查找您的主类。执行命令>编辑配置。为main类添加主类，并将项目的根目录添加为Working目录。

如果你想使用Java 10之外的AdoptOpenJDK发行版，你可以使用AdoptOpenJDK网站上描述的官方存储库(也适用于Debian):

Import the official AdoptOpenJDK GPG key by running the following command: wget -qO - https://adoptopenjdk.jfrog.io/adoptopenjdk/api/gpg/key/public | sudo apt-key add - Import the AdoptOpenJDK DEB repository by running the following command: sudo add-apt-repository --yes https://adoptopenjdk.jfrog.io/adoptopenjdk/deb/ If you get a command not found error, try running: apt-get install -y software-properties-common Then repeat the first command. Refresh your package list with apt-get update and then install your chosen AdoptOpenJDK package. For example, to install OpenJDK 8 with the HotSpot VM, run: apt-get install <adoptopenjdk-8-hotspot>

您可以在https://adoptopenjdk.jfrog.io/adoptopenjdk/deb/pool/main/a/下找到可用的软件包名称/ Java版本

参考问Ubuntu问题如何设置OpenJDK的JAVA_HOME ?，

如何在Ubuntu (Linux)下安装Open JDK (Java开发工具包)?

Open Terminal from Application Dash or press Ctrl+Alt+T Update repository: sudo add-apt-repository ppa:openjdk-r/ppa # only Ubuntu 17.4 and earlier sudo apt update Optional: To search available distributions of openjdk, use the following command: apt search openjdk Install the appropriate version with the following command: sudo apt install openjdk-8-jdk sudo apt install openjdk-8-source #this is optional, the jdk source code For JAVA_HOME (Environment Variable) type command as shown below, in "Terminal" using your installation path... export JAVA_HOME=/usr/lib/jvm/java-8-openjdk (Note: /usr/lib/jvm/java-8-openjdk is symbolically used here just for demostration. You should use your path as per your installation.) For PATH (Environment Variable) type command as shown below, in Terminal: export PATH=$PATH:$JAVA_HOME/bin To check your installation: java -version