我无法按照此链接中提供的步骤安装oracle java 7：
http://www.webupd8.org/2012/09/install-oracle-java-8-in-ubuntu-via-ppa.html
http://www.webupd8.org/2012/09/install-oracle-java-8-in-ubuntu-via-ppa.html
sudo add-apt-repository ppa:webupd8team/java sudo apt-get update sudo apt-get install oracle-java7-installer
我得到以下内容：
Reading package lists... Done
Building dependency tree
Reading state information... Done
Suggested packages:
visualvm ttf-baekmuk ttf-unfonts ttf-unfonts-core ttf-kochi-gothic
ttf-sazanami-gothic ttf-kochi-mincho ttf-sazanami-mincho ttf-arphic-uming
The following NEW packages will be installed:
oracle-java7-installer
0 upgraded,1 newly installed,0 to remove and 0 not upgraded.
Need to get 0 B/18,6 kB of archives.
After this operation,193 kB of additional disk space will be used.
Preconfiguring packages ...
Selecting prevIoUsly unselected package oracle-java7-installer.
(Reading database ... 273801 files and directories currently installed.)
Unpacking oracle-java7-installer (from .../oracle-java7-installer_7u51-0~webupd8~4_all.deb) ...
oracle-license-v1-1 license has already been accepted
Processing triggers for desktop-file-utils ...
Processing triggers for bamfdaemon ...
Rebuilding /usr/share/applications/bamf.index...
Processing triggers for gnome-menus ...
Processing triggers for shared-mime-info ...
Setting up oracle-java7-installer (7u51-0~webupd8~4) ...
Downloading Oracle Java 7...
--2014-03-20 12:12:52-- http://download.oracle.com/otn-pub/java/jdk/7u51-b13/jdk-7u51-linux-x64.tar.gz
Resolving download.oracle.com (download.oracle.com)... 131.178.7.201
Connecting to download.oracle.com (download.oracle.com)|131.178.7.201|:80... connected.
HTTP request sent,awaiting response... 302 Moved Temporarily
Location: https://edelivery.oracle.com/otn-pub/java/jdk/7u51-b13/jdk-7u51-linux-x64.tar.gz [following]
--2014-03-20 12:12:52-- https://edelivery.oracle.com/otn-pub/java/jdk/7u51-b13/jdk-7u51-linux-x64.tar.gz
Resolving edelivery.oracle.com (edelivery.oracle.com)... 23.204.22.140
Connecting to edelivery.oracle.com (edelivery.oracle.com)|23.204.22.140|:443... connected.
HTTP request sent,awaiting response... 302 Moved Temporarily
Location: http://download.oracle.com/otn-pub/java/jdk/7u51-b13/jdk-7u51-linux-x64.tar.gz?AuthParam=1395339292_7fc586697ce74b02fa16cb3ec88d3a9d [following]
--2014-03-20 12:12:52-- http://download.oracle.com/otn-pub/java/jdk/7u51-b13/jdk-7u51-linux-x64.tar.gz?AuthParam=1395339292_7fc586697ce74b02fa16cb3ec88d3a9d
Connecting to download.oracle.com (download.oracle.com)|131.178.7.201|:80... connected.
HTTP request sent,awaiting response... 416 Requested Range Not Satisfiable
The file is already fully retrieved; nothing to do.
Download done.
Removing outdated cached downloads...
sha256sum mismatch jdk-7u51-linux-x64.tar.gz
Oracle JDK 7 is NOT installed.
dpkg: error processing oracle-java7-installer (--configure):
subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
oracle-java7-installer
E: Sub-process /usr/bin/dpkg returned an error code (1)
我也尝试过做https://help.ubuntu.com/community/Java所说的话：
sudo rm /var/lib/dpkg/info/oracle-java7-installer* sudo apt-get purge oracle-java7-installer* sudo rm /etc/apt/sources.list.d/*java* sudo apt-get update
然后：
sudo add-apt-repository ppa:webupd8team/java sudo apt-get update sudo apt-get install oracle-java7-installer
仍然没有运气:(
谁能帮助我？
我很遗憾为什么它不起作用.
提前致谢.
编辑：在以下链接中找到解决方案：https://askubuntu.com/questions/414885/oracle-jdk-7-is-not-installed-error
解：
sudo dpkg -P oracle-java7-installer sudo apt-get -f install sudo apt-get install oracle-java7-installer
请按照以下步骤安装oracle java：
下载最新的Java SE SDK版本.
http://www.oracle.com/technetwork/java/javase/downloads/index.html
解压档案：
tar -xzvf jdk-8-linux-x64.tar.gz mv jdk1.8.0 /opt cd /opt/jdk1.8.0
此步骤将下载的Java版本注册为替代,并将其切换为默认值：
update-alternatives --install /usr/bin/java java /opt/jdk1.8.0/bin/java 1 update-alternatives --install /usr/bin/javac javac /opt/jdk1.8.0/bin/javac 1 update-alternatives --install /usr/lib/mozilla/plugins/libjavaplugin.so mozilla-javaplugin.so /opt/jdk1.8.0/jre/lib/amd64/libnpjp2.so 1 update-alternatives --set java /opt/jdk1.8.0/bin/java update-alternatives --set javac /opt/jdk1.8.0/bin/javac update-alternatives --set mozilla-javaplugin.so /opt/jdk1.8.0/jre/lib/amd64/libnpjp2.so
测试
检查您正在运行的Java版本
java -version
产量
java version "1.8.0" Java(TM) SE Runtime Environment (build 1.8.0-b132) Java HotSpot(TM) 64-Bit Server VM (build 25.0-b70,mixed mode)
要检查浏览器插件,请浏览到http://www.java.com/,然后单击“我有Java吗？”
参考：https://askubuntu.com/questions/437776/ubuntu-13-04-unable-to-install-jdk7