ModuleLifecycle

fr.capellegab.api.module.ModuleLifecycle

Optional interface to react to module lifecycle events.

Definition

public interface ModuleLifecycle {
    default void onStart() {}
    default void onStop() {}
    default void onError(Event event, Exception exception) {}
}

Methods

All methods are default — only implement the ones you need.

onStart()

Called once when the module is loaded by the core. Use it to initialize resources.

@Override
public void onStart() {
    // Initialize a connection, load a cache, etc.
}

onStop()

Called when the core shuts down. Use it to release resources.

@Override
public void onStop() {
    // Close connections, flush buffers, etc.
}

onError(Event event, Exception exception)

Called when onEvent() throws an exception. Allows logging, alerting, or deciding on a retry strategy.

Parameter	Type	Description
event	Event	The event that caused the error
exception	Exception	The thrown exception

@Override
public void onError(Event event, Exception exception) {
    System.err.println("Error on " + event.uuid() + ": " + exception.getMessage());
}

Full example

public class MyModule implements EventModule, ModuleLifecycle {

    private Connection connection;

    @Override
    public ModuleConfig config() {
        return new ModuleConfig("my-module", "1.0.0", "author", "Description", Set.of(EventType.TRANSACTION), Priority.MEDIUM);
    }

    @Override
    public void onStart() {
        connection = Database.connect();
    }

    @Override
    public void onEvent(Event event, EventContext context) {
        connection.save(event);
    }

    @Override
    public void onError(Event event, Exception exception) {
        context.log("Failed to save event {}: {}", event.uuid(), exception.getMessage());
    }

    @Override
    public void onStop() {
        connection.close();
    }
}