我尝试运行此代码，但它不起作用，因为 Producer.send() 不接受 KeyedMessage 类型。
我尝试导入 kafka.javaapi. Producer.Producer 而不是 kafka. Producer.Producer ；但还是不行
代码是:
package sources;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Properties;
//import kafka.javaapi.producer.Producer;
import kafka.producer.KeyedMessage;
import kafka.producer.ProducerConfig;
import kafka.javaapi.producer.Producer;
//import kafka.producer.Producer;
public class ProducerCode {
private static Producer<Integer, String> producer;
private static final String topic= "mytopic";
public void initialize() {
Properties producerProps = new Properties();
producerProps.put("metadata.broker.list", "localhost:9092");
producerProps.put("serializer.class", "kafka.serializer.StringEncoder");
producerProps.put("request.required.acks", "1");
// ProducerConfig producerConfig = new ProducerConfig(producerProps);
// have a change here **
producer = new Producer<Integer, String>(new ProducerConfig(producerProps));
}
public void publishMesssage() throws Exception{
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
while (true){
System.out.print("Enter message to send to kafka broker (Press 'Y' to close producer): ");
String msg = null;
msg = reader.readLine(); // Read message from console
//Define topic name and message
KeyedMessage<Integer, String> keyedMsg = new KeyedMessage<Integer, String>(topic, msg);
producer.send(keyedMsg);
// producer.send(keyedMsg); // This publishes message on given topic
if("Y".equals(msg)){ break; }
System.out.println("--> Message [" + msg + "] sent.Check message on Consumer's program console");
}
return;
}
public static void main(String[] args) throws Exception {
KafkaProducer kafkaProducer = new KafkaProducer();
// Initialize producer
kafkaProducer.initialize();
// Publish message
kafkaProducer.publishMesssage();
//Close the producer
producer.close();
}
}
最佳答案
您必须使用ProducerRecord (而不是 KeyedMessage )与构造函数 ProducerRecord(String topic, K key, V value)
Producer<String, String> producer = new KafkaProducer<>(props);
producer.send(new ProducerRecord<String, String>("my-topic", "key", "value"));
关于java - Producer.send 不接受 KeyedMessage 类型，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/38578361/