Kafka Log4j2 appender doesn't send last log event to the topic

I want to configure log4j2 kafka appender for sending log events to a Kafka topic. I have used below configurations. Everything is working well expect missing last log event. For getting last log event to kafka topic it has to generate another log event unless last log event is not come to kafka topic.

appender.kafka.name=KafkaAppender
appender.kafka.type=Kafka
appender.kafka.topic=TestTopic
appender.kafka.bootstrapServers.type=Property
appender.kafka.bootstrapServers.name=bootstrap.servers
appender.kafka.bootstrapServers.value=localhost:9092

appender.kafka.layout.type = PatternLayout
appender.kafka.layout.pattern =%d %p %C{1.} [%t] %m%n

rootLogger.level = info
rootLogger.appenderRef.stdout.ref = STDOUT
rootLogger.appenderRef.rolling.ref = RollingFile
rootLogger.appenderRef.kafka.ref=KafkaAppender

any solution rather than generating dummy log event at the end.