I am an experienced Java programmer who received the Raspberry Pi for Christmas. Unfortunately, it appears that only Python is installed in it. What command do I type at the start command line where I would usually type startx to install the JDK and JRE?
[Note: Later in 2013 the Pi Foundation announced Raspbian now ships with Oracle hard-float.]
The oracle 8 preview works for me, thus far. Compiling is slow on the pi, surprise, but the jre seems to run quite fast once it loads. I think bearbin's answer is pretty definitive but if you want a simple way to try oracle:
- Download. You get a .tar.gz file, which is a gzipped tarball.
- Put the .tar.gz in
/usr/localand unpack it:
tar -xzf oracle8-blah-blah.tar.gz. This will create a directory with everything in it. You can rename the directory,
mv oracle-jdk-whatever jdk1.8.0. Everything in there is self-contained.
- Put the bin/ directory at the beginning of your executable search $PATH. If there are any other javas installed, that will make this one take precedence:
That will only work for your current shell. To make it the default from now on, add this to
Note you must log in again to make
.profile effective. However, if you are using
lightdm, the default GUI login won't do this, see here for a solution.
To install the Java Runtime Environment (JRE) run the following command:
sudo apt-get install openjdk-7-jre
This installs the Java JRE (Java Runtime Environment) which will allow you to run applications written in Java.
To install the JDK run the command:
sudo apt-get install openjdk-7-jdk
This allows you to compile Java applications to bytecode.
If you want the Oracle Java VM, which is a lot faster (optimized for embedded arm CPUs) and is also a developer preview (applications maybe buggy or crash) until some time into the future. Instead of the above instructions you need to download the file called
Oracle JDK 8 (with JavaFX) for ARM Early Access on the Oracle Java 8 download page.
Remember to download the Oracle Java system on your Pi, or you won't be able to install it.
To install the Oracle Java System:
sudo tar zxvf jdk-8-ea-b36e-linux-arm-hflt-*.tar.gz -C /opt sudo update-alternatives --install "/usr/bin/java" "java" "/opt/jdk1.8.0/bin/java" 1 sudo update-alternatives for other commands if needed (e.g. javac). java -version
Then it is all installed.
Another thing, if you have more then one Java runtime installed you have to check which version you use with the command
java -version. If the output is:
java version 1.5.0 gij (GNU libgij)
Then you are using another java runtime. You can resolve the issue by running
sudo update-alternatives --config java
and choosing the OpenJDK or Oracle option.
Installing Oracle Java 7 JDK (but not JRE) hard-float for RPi is now as stunningly easy as:
sudo apt-get update && sudo apt-get install oracle-java7-jdk
I used to go through the old processes that were linked above, but since they easyfied it, now I just do this.
Oracle have provided a step by step guide of how to setup Java SE Embedded on a Raspberry Pi device. They include information on the essential linux setup and some details of optional tweaking/optimisations
Detailed instructions for Java SE Embedded from Oracle are provided here.
Nowadays, instead of the Early Access JDK 8, you can install the hardfloat version of Oracle JDK 7, which has full support from Oracle (unlike the JDK 8).
Oracle's current download page (the same as other Java releases): http://www.oracle.com/technetwork/java/javase/downloads/index.html
(No JRE is available, you need to download the full JDK).
For installation, you can refer to bearbin's answer.