# jdk 标签
https://www.fosstechnix.com/install-oracle-java-8-on-ubuntu-20-04/ 下载 jdk-8u251-linux-x64.tar.gz 解压 sudo mkdir -p /opt/jdk # 解压后放到/opt/jdk Install Oracle Java 8 on Ubuntu 20.04 LTS with Alternatives sudo update-alternatives --install /usr/bin/java java /opt/jdk/jdk1.8.0_251/bin/java 100 如果有多个版本可以这么切换 sudo update-alternatives --config java 配置环境变量 # 编辑 /etc/environment ，填入以下内容 JAVA_HOME=/opt/jdk/jdk1.8.0_251 JRE_HOME=/opt/jdk/jdk1.8.0_251/jre # 使生效 source /etc/environment

Ubuntu：安装 Oracle JDK8