我正在使用 Oracle VM Virtual Box（版本 5.1.18）来运行 Ubuntu 16.04。我正在使用代理服务器。我已在apt.conf和中配置了代理设置apt.config。在这两个文件中，我的 http 代理都设置了用户名、密码、主机、地址，并且我的网络运行正常。我已经能够安装 openjdk-8 版本。我的jdk 版本是
openjdk version "1.8.0_131"
OpenJDK Runtime Environment (build 1.8.0_131-8u131-b11-2ubuntu1.16.04.3-b11)
OpenJDK 64-Bit Server VM (build 25.131-b11, mixed mode)
我正在尝试使用命令安装 Java 8
sudo apt-get install oracle-java8-installer
但这是我得到的错误
Package oracle-java8-installer is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'oracle-java8-installer' has no installation candidate
我在某处读到我需要使用命令sudo apt install snapd
但这是它显示的错误
Setting up snapd (2.26.10~14.04) ...
Failed to execute operation: No such file or directory
dpkg: error processing package snapd (--configure):
subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of snap-confine:
snap-confine depends on snapd (= 2.26.10~14.04); however:
Package snapd is not configured yet.
dpkg: error processing package snap-confine (--configure):
dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of ubuntu-core-launcher:
ubuntu-core-launcher depends on snap-confine (= 2.26.10~14.04); however:
Package snap-confine is not configured yet.
dpkg: error processing package ubuntu-core-launcher (--configure):
dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
No apport report written because the error message indicates its a followup error from a previous failure.
Errors were encountered while processing:
snapd
snap-confine
ubuntu-core-launcher
E: Sub-process /usr/bin/dpkg returned an error code (1)
如能得到任何帮助我将非常感激，过去一天我一直试图安装 Java，但失败了。
编辑
使用时也会sudo add-apt-repository ppa:webupd8team/java出现此错误-
Cannot add PPA: 'ppa:~webupd8team/ubuntu/java'.
ERROR: '~webupd8team' user or team does not exist.
我提到过这个链接Oracle-Java8-Installer：没有安装候选项。
webupd8team-java.list在此链接中的第一个答案中，没有这样的文件/etc/apt/sources.list.d
而在第二个答案中，此命令sudo apt-get install python-software-properties会产生与以下相同的错误sudo apt install snapd
Failed to execute operation: No such file or directory
dpkg: error processing package snapd (--configure):
subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of snap-confine:
snap-confine depends on snapd (= 2.26.10~14.04); however:
Package snapd is not configured yet.
dpkg: error processing package snap-confine (--configure):
dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of ubuntu-core-launcher:
ubuntu-core-launcher depends on snap-confine (= 2.26.10~14.04); however:
Package snap-confine is not configured yet.
dpkg: error processing package ubuntu-core-launcher (--configure):
dependency problems - leaving unconfigured
Setting up python-apt (1.1.0~beta1build1) ...
No apport report written because the error message indicates its a followup
error from a previous failure.
No apport report written because the error message
indicates its a followup error from a previous failure.
Setting up python-pycurl (7.43.0-1ubuntu1) ...
Setting up python-software-properties (0.96.20.7) ...
Errors were encountered while processing:
snapd
snap-confine
ubuntu-core-launcher
E: Sub-process /usr/bin/dpkg returned an error code (1)