Springboot2.x集成kafka2.2.0

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.4.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
  </parent>
  <groupId>com.example</groupId>
  <artifactId>demo</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <name>kafkademo</name>
  <description>Demo project for Spring Boot</description>
  <properties>
    <java.version>1.8</java.version>
  </properties>
  <dependencies>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <scope>runtime</scope>
    </dependency>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-test</artifactId>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.springframework.kafka</groupId>
      <artifactId>spring-kafka</artifactId>
      <version>2.2.0.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>com.google.code.gson</groupId>
      <artifactId>gson</artifactId>
      <version>2.7</version>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
</project>

spring.kafka.bootstrap-servers=2.1.1.1:9092
spring.kafka.consumer.group-id=test-consumer-group
spring.kafka.consumer.key-deserializer=org.apache.kafka.common.serialization.StringDeserializer
spring.kafka.consumer.value-deserializer=org.apache.kafka.common.serialization.StringDeserializer
spring.kafka.producer.key-serializer=org.apache.kafka.common.serialization.StringSerializer
spring.kafka.producer.value-serializer=org.apache.kafka.common.serialization.StringSerializer
#logging.level.root=debug

package com.example.demo.model;
import java.util.Date;
public class Messages {
    private Long id;
    private String msg;
    private Date sendTime;
    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }
    public String getMsg() {
        return msg;
    }
    public void setMsg(String msg) {
        this.msg = msg;
    }
    public Date getSendTime() {
        return sendTime;
    }
    public void setSendTime(Date sendTime) {
        this.sendTime = sendTime;
    }
}

package com.example.demo.service;
import com.example.demo.model.Messages;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.kafka.support.SendResult;
import org.springframework.stereotype.Service;
import org.springframework.util.concurrent.ListenableFuture;
import java.util.Date;
import java.util.UUID;
@Service
public class KafkaSender {
    @Autowired
    private KafkaTemplate<String, String> kafkaTemplate;
    private Gson gson = new GsonBuilder().create();
    public void send() {
        Messages message = new Messages();
        message.setId(System.currentTimeMillis());
        message.setMsg("123");
        message.setSendTime(new Date());
        ListenableFuture<SendResult<String, String>> test0 = kafkaTemplate.send("newtopic", gson.toJson(message));
    }
}

package com.example.demo.service;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.springframework.kafka.annotation.KafkaListener;
import org.springframework.stereotype.Service;
import java.util.Optional;
@Service
public class KafkaReceiver {
    @KafkaListener(topics = {"newtopic"})
    public void listen(ConsumerRecord<?, ?> record) {
        Optional<?> kafkaMessage = Optional.ofNullable(record.value());
        if (kafkaMessage.isPresent()) {
            Object message = kafkaMessage.get();
            System.out.println("record =" + record);
            System.out.println("message =" + message);
        }
    }
}

package com.example.demo;
import com.example.demo.service.KafkaSender;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
@SpringBootApplication
public class KafkademoApplication {
  public static void main(String[] args) {
    ConfigurableApplicationContext context = SpringApplication.run(KafkademoApplication.class, args);
    KafkaSender sender = context.getBean(KafkaSender.class);
    for (int i = 0; i <1000; i++) {
      sender.send();
      try {
        Thread.sleep(300);
      } catch (InterruptedException e) {
        e.printStackTrace();
      }
    }
  }
}

at org.apache.kafka.common.network.NetworkReceive.readFrom(NetworkReceive.java:119)