当我运行 sudo apt update 时出现以下错误：
Hit:1 http://in.archive.ubuntu.com/ubuntu focal InRelease
Hit:2 http://in.archive.ubuntu.com/ubuntu focal-updates InRelease
Hit:3 http://in.archive.ubuntu.com/ubuntu focal-backports InRelease
Hit:4 http://dl.google.com/linux/chrome/deb stable InRelease
Hit:5 http://in.archive.ubuntu.com/ubuntu focal-security InRelease
Hit:6 http://in.archive.ubuntu.com/ubuntu focal-proposed InRelease
Hit:7 http://ppa.launchpad.net/kivy-team/kivy-daily/ubuntu focal InRelease
Hit:8 http://ppa.launchpad.net/kivy-team/kivy/ubuntu focal InRelease
Ign:9 http://ppa.launchpad.net/webupd8team/java/ubuntu focal InRelease
Err:10 http://ppa.launchpad.net/webupd8team/java/ubuntu focal Release
404 Not Found [IP: 2001:67c:1560:8008::15 80]
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/webupd8team/java/ubuntu focal Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
如何修复此问题并更新！！！
答案1
Webupd8 团队的 Oracle Java (JDK) 8 安装程序 PPA 已停产。
https://launchpad.net/~webupd8team/+archive/ubuntu/java
您必须删除这个 ppa。
要安装 Java (15)，请参阅：
https://www.linuxuprising.com/2020/09/how-to-install-oracle-java-15-on-ubuntu.html