如何将Flink连接到运行在不同机器上的Kafka？

<dependency>
    <groupId>org.apache.flink</groupId>
    <artifactId>flink-connector-kafka_2.11</artifactId>
    <version>${flink.version}</version>
</dependency>

Properties properties = new Properties();
properties.setProperty("bootstrap.servers", "kafka1:9092,kafka2:9092,kafka3:9092");
properties.setProperty("group.id", "flink-consumer-group");

FlinkKafkaConsumer<String> kafkaConsumer = new FlinkKafkaConsumer<>("my-topic", new SimpleStringSchema(), properties);

Properties properties = new Properties();
properties.setProperty("bootstrap.servers", "kafka1:9092,kafka2:9092,kafka3:9092");

FlinkKafkaProducer<String> kafkaProducer = new FlinkKafkaProducer<>("my-topic", new SimpleStringSchema(), properties);

DataStream<String> kafkaStream = env.addSource(kafkaConsumer);
kafkaStream.print();

// 或者

dataStream.addSink(kafkaProducer);