JNRPE - Java Nagios Remote Plugin Executor

JNRPE allows the execution of both native and Java Nagios plugins without the overhead of a new JVM instance for each java plugin execution.

Overview

Nagios will invoke a check defined as a check_nrpe command.
check_nrpe will invoke the command on the JNRPE server
The Socket Listener (that implements the NRPE protocol) will parse and validate the received packet. If the packet is valid, it will ask the executor to execute the received command.
The executor will ask the Command Registry to retrieve the command definition for the requested command
After receiving the command, the executor will ask the command definition to create a COMMAND INSTANCE passing to the command definition all the received parameters. A COMMAND INSTANCE will contain teh requested plugin and all the parameters (replacing the $ARGx$ macros if needed).
When a COMMAND INSTANCE is received, the executor will execute the command instance and return the result to the Socket Listener.
The Socket Listener will then create a NRPE packet with the received result and will return that to check_nrpe.
check_nrpe returns the check result to Nagios

# ./gradlew build

# ./gradlew run

After gradlew build the distribution files can be found into the it.jnrpe.server/build/distributions folder.