Java is available on the cluster. Activate java by loading the Java module
```console
$ml Java
```
Note that the Java module must be loaded on the compute nodes as well, in order to run java on compute nodes.
Check for java version and path
```console
$java -version
$which java
```
With the module loaded, not only the runtime environment (JRE), but also the development environment (JDK) with the compiler is available.
```console
$javac -version
$which javac
```
Java applications may use MPI for inter-process communication, in conjunction with Open MPI. Read more on <http://www.open-mpi.org/faq/?category=java>. This functionality is currently not supported on Anselm cluster. In case you require the java interface to MPI, please contact [cluster support](https://support.it4i.cz/rt/).
The operating system on Anselm is Linux - [**Red Hat Enterprise Linux release 6.x**](https://en.wikipedia.org/wiki/Red_Hat_Enterprise_Linux).
# Salomon
The operating system on Salomon is Linux - [**CentOS 6.x**](https://en.wikipedia.org/wiki/CentOS)
The CentOS Linux distribution is a stable, predictable, manageable and reproducible platform derived from the sources of Red Hat Enterprise Linux (RHEL).