Follow the instructions before compiling the project.
In linux:
- Open terminal in the root directory of this project and execute the commands.
 $ cd src/main/resources
 $ mkdir certs && cd certs
 $ openssl genrsa -out keypair.pem 2048
 $ openssl rsa -in keypair.pem -pubout -out public.pem
 $ openssl pkcs8 -topk8 -inform PEM -outform PEM -nocrypt -in keypair.pem -out private.pem
 $ rm keypair.pem