在运行最新 debian 映像的 docker 容器上，我无法安装该openjdk-8-jdk软件包。为什么不突然？
$ apt-get install openjdk-8-jdk
E: Unable to locate package openjdk-8-jdk
为什么不呢，它是：https : //packages.debian.org/stretch/openjdk-8-jdk
Debian 版本：
$ cat /etc/os-release
PRETTY_NAME="Debian GNU/Linux 10 (buster)"
NAME="Debian GNU/Linux"
VERSION_ID="10"
VERSION="10 (buster)"
VERSION_CODENAME=buster
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"
搜索 openjdk-8-jdk 包：
apt-cache search --names-only '^openjdk-8*'
openjdk-11-dbg - Java runtime based on OpenJDK (debugging symbols)
openjdk-11-demo - Java runtime based on OpenJDK (demos and examples)
openjdk-11-doc - OpenJDK Development Kit (JDK) documentation
openjdk-11-jdk - OpenJDK Development Kit (JDK)
openjdk-11-jdk-headless …