Question

如何用Java向kafka发送json数据

Answer 1

发送json也可以看成字符串处理
We have 2 Options as listed below

1) If we intend to send custom java objects to producer, We need to create a serializer which implements org.apache.kafka.common.serialization.Serializer and pass that Serializer class during creation of your producer

Code Reference below

public class PayloadSerializer implements org.apache.kafka.common.serialization.Serializer {

public void configure(Map map, boolean b) {

}

public byte[] serialize(String s, Object o) {

try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(baos);
oos.writeObject(o);
oos.close();
byte[] b = baos.toByteArray();
return b;
} catch (IOException e) {
return new byte[0];
}
}

public void close() {

}
}
And set the value serializer accordingly

<entry key="value.serializer"
value="com.spring.kafka.PayloadSerializer" />
2) No need to create custom serializer class. Use the existing ByteArraySerializer, but during send follow the process

Java Object -> String (Preferrably JSON represenation instead of toString)->byteArray

Answer 2

文档，序列化成String就行了