in log4j-server/src/main/java/org/apache/logging/log4j/server/AbstractSocketServer.java [176:179]
public AbstractSocketServer(final int port, final LogEventBridge<T> logEventInput) {
this.logger = LogManager.getLogger(this.getClass().getName() + '.' + port);
this.logEventInput = Objects.requireNonNull(logEventInput, "LogEventInput");
}