mxjava (previously named erdjava) is an SDK written in Java, useful for interacting with the MultiversX Network.
Make sure you have a JDK and the JRE installed. Furthermore, maven is also required.
On Ubuntu, you can install them as follows:
sudo apt install default-jdk
sudo apt install default-jre
sudo apt install maven
mxjava can be fetched directly from Maven central repository.
Alternatively, you can use:
git clone --depth 1 -b main https://github.com/multiversx/mx-sdk-java.git
cd mx-sdk-java
mvn test