Ubuntu: OpenJDK 8 - Unable to locate package
I'm getting OpenJDK 8 from the official Debian repositories, rather than some random PPA or non-free Oracle binary. Here's how I did it:
sudo apt-get install debian-keyring debian-archive-keyring
Make /etc/apt/sources.list.d/debian-jessie-backports.list:
deb http://httpredir.debian.org/debian/ jessie-backports main
Make /etc/apt/preferences.d/debian-jessie-backports:
Package: *
Pin: release o=Debian,a=jessie-backports
Pin-Priority: -200
Then finally do the install:
sudo apt-get update
sudo apt-get -t jessie-backports install openjdk-8-jdk
sudo apt-get update
sudo apt-get install openjdk-8-jdk
this should work
As you can see I only have java 1.7 installed (on a Ubuntu 14.04 machine).
update-java-alternatives -l
java-1.7.0-openjdk-amd64 1071 /usr/lib/jvm/java-1.7.0-openjdk-amd64
To install Java 8, I did,
sudo add-apt-repository ppa:openjdk-r/ppa
sudo apt-get update
sudo apt-get install openjdk-8-jdk
Afterwards, now I have java 7 and 8,
update-java-alternatives -l
java-1.7.0-openjdk-amd64 1071 /usr/lib/jvm/java-1.7.0-openjdk-amd64
java-1.8.0-openjdk-amd64 1069 /usr/lib/jvm/java-1.8.0-openjdk-amd64
BONUS ADDED (how to switch between different versions)
- run the follwing command from the terminal:
sudo update-alternatives --config javaThere are 2 choices for the alternative java (providing /usr/bin/java). Selection Path Priority Status ------------------------------------------------------------ 0 /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java 1071 auto mode 1 /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java 1071 manual mode * 2 /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java 1069 manual mode Press enter to keep the current choice[*], or type selection number:
As you can see I'm running open jdk 8. To switch to to jdk 7, press 1 and hit the Enter key. Do the same for javac as well with, sudo update-alternatives --config javac.
Check versions to confirm the change: java -version and javac -version.
UPDATE: installation without root privileges below
I advise you to not install packages manually on ubuntu system if there is already a (semi-official) repository able to solve your problem. Further, use Oracle JDK for development, just to avoid (very sporadic) compatibility issues (i've tried many years ago, it's surely better now).
Add the webupd8 repo to your system:
sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
Install your preferred version of jdk (versions from java-6 to java-9 available):
sudo apt-get install oracle-java8-installer
You can also install multiple version of jdk, mixing openjdk and oracle versions. Then you can use the command update-java-alternatives to switch between installed version:
# list available jdk
update-java-alternatives --list
# use jdk7
sudo update-java-alternatives --set java-7-oracle
# use jdk8
sudo update-java-alternatives --set java-8-oracle
Requirements
If you get add-apt-repository: command not found be sure to have software-properties-common installed:
sudo apt-get install software-properties-common
If you're using an older version Ubuntu:
sudo apt-get install python-software-properties
JDK installation without root privileges
If you haven't administrator rights on your target machine your simplest bet is to use sdkman to install the zulu certified openjdk:
curl -s "https://get.sdkman.io" | bash
source "$HOME/.sdkman/bin/sdkman-init.sh"
sdk install java
NOTE: sdkman allow to install also the official Oracle JDK, although it's not a the default option. View available versions with:
sdk ls java
Install the chosen version with:
sdk install java <version>
For example:
sdk install java 9.0.1-oracle
Glossary of commands
sudo
<command> [command_arguments]: execute a command with the superuser privilege.add-apt-repository
<PPA_id>: Ubuntu (just like every Debian derivatives and generally speaking every Linux distribution) has a main repository of packages that handle things like package dependencies and updating. In Ubuntu is possible to extend the main repository using a PPA (Personal Package Archive) that usually contains packages not available in the system (just like oracle jdk) or updated versions of available ones (example: LibreOffice 5 in LTS is available only through this PPA).apt-get
[install|update|upgrade|purge|...]: it's "the" command-line package handler used to manipulate the state of every repository on the system (installing / updating / upgrading can be viewed as an alteration of the repository current state).
In our case: with the command sudo add-apt-repository ppa:webupd8team/java we inform the system that the next repository update must retrieve packages information also from webupd8 repo.
With sudo apt-get update we actually update the system repository (all this operations requires superuser privileges, so we prepend sudo to the commands).
sudo apt-get install oracle-java8-installer
update-java-alternatives (a specific java version of update-alternatives): in Ubuntu several packages provides the same functionality (browse the internet, compile mails, edit a text file or provides java/javac executables...). To allows the system to choose the user favourites tool given a specific task a mechanism using symlinks under
/etc/alternatives/is used. Try to update the jdk as indicated above (switch between java 7 and java 8) and view how change the output of this command:ls -l /etc/alternatives/java*
In our case: sudo update-java-alternatives --set java-8-oracle update symlinks under /etc/alternatives to point to java-8-oracle executables.
Extras:
man
<command>: start using man to read a really well written and detailed help on (almost) every shell command and its options (every command i mention in this little answer has a man page, tryman update-java-alternatives).apt-cache
search <search_key>: query the APT cache to search for a package related with the search_key provided (can be the package name or some word in package description).apt-cache
show <package>: provides APT information for a specific package (package version, installed or not, description).