史上最差的kafka教程第三天（简单案例代码）

导入依赖

　　　　　<dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-clients</artifactId>
            <version>2.4.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.kafka</groupId>
            <artifactId>kafka-streams</artifactId>
            <version>2.4.0</version>
        </dependency>

 

 

kafka配置类

/**
 * @ClassName
 * @Description TODO
 * @AUTHOR admin
 * @DATE 2020/6/29 17:35
 */
@Configuration
@EnableKafka
public class KafkaConfiguration {
    //ConcurrentKafkaListenerContainerFactory为创建Kafka监听器的工程类，这里只配置了消费者
    @Bean
    public ConcurrentKafkaListenerContainerFactory<Integer, String> kafkaListenerContainerFactory() {
        ConcurrentKafkaListenerContainerFactory<Integer, String> factory = new ConcurrentKafkaListenerContainerFactory<>();
        factory.setConsumerFactory(consumerFactory());
        return factory;
    }

    //根据consumerProps填写的参数创建消费者工厂
    @Bean
    public ConsumerFactory<Integer, String> consumerFactory() {
        return new DefaultKafkaConsumerFactory<>(consumerProps());
    }

    //根据senderProps填写的参数创建生产者工厂
    @Bean
    public ProducerFactory<Integer, String> producerFactory() {
        return new DefaultKafkaProducerFactory<>(senderProps());
    }

    //kafkaTemplate实现了Kafka发送接收等功能
    @Bean
    public KafkaTemplate<Integer, String> kafkaTemplate() {
        KafkaTemplate template = new KafkaTemplate<Integer, String>(producerFactory());
        return template;
    }

    //消费者配置参数
    private Map<String, Object> consumerProps() {
        Map<String, Object> props = new HashMap<>();
        //连接地址
        props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, "127.0.0.1:9092");
        //GroupID
        props.put(ConsumerConfig.GROUP_ID_CONFIG, "bootKafka");
        //是否自动提交
        props.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, true);
        //自动提交的频率
        props.put(ConsumerConfig.AUTO_COMMIT_INTERVAL_MS_CONFIG, "1000");
        //Session超时设置
        props.put(ConsumerConfig.SESSION_TIMEOUT_MS_CONFIG, "15000");
        //键的反序列化方式
        props.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, IntegerDeserializer.class);
        //值的反序列化方式
        props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
        return props;
    }

    //生产者配置
    private Map<String, Object> senderProps (){
        Map<String, Object> props = new HashMap<>();
        //连接地址
        props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "192.168.137.4:9092");
        //重试，0为不启用重试机制
        props.put(ProducerConfig.RETRIES_CONFIG, 1);
        //控制批处理大小，单位为字节
        props.put(ProducerConfig.BATCH_SIZE_CONFIG, 16384);
        //批量发送，延迟为1毫秒，启用该功能能有效减少生产者发送消息次数，从而提高并发量
        props.put(ProducerConfig.LINGER_MS_CONFIG, 1);
        //生产者可以使用的总内存字节来缓冲等待发送到服务器的记录
        props.put(ProducerConfig.BUFFER_MEMORY_CONFIG, 1024000);
        //键的序列化方式
        props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, IntegerSerializer.class);
        //值的序列化方式
        props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
        return props;
    }
}

 

 

 

生产者示例代码

public class ProducerSample {

 　　/*
        Producer异步发送带回调函数和Partition负载均衡
     */
    public static void producerSendWithCallbackAndPartition(){
        Properties properties = new Properties();
      //  properties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,"192.168.220.128:9092");
        properties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,"127.0.0.1:9092");
        properties.put(ProducerConfig.ACKS_CONFIG,"all");
        properties.put(ProducerConfig.RETRIES_CONFIG,"0");
        properties.put(ProducerConfig.BATCH_SIZE_CONFIG,"16384");
        properties.put(ProducerConfig.LINGER_MS_CONFIG,"1");
        properties.put(ProducerConfig.BUFFER_MEMORY_CONFIG,"33554432");

        properties.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG,"org.apache.kafka.common.serialization.StringSerializer");
        properties.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG,"org.apache.kafka.common.serialization.StringSerializer");
        properties.put(ProducerConfig.PARTITIONER_CLASS_CONFIG,"com.sun4cloud.sunx.kafka.producer.SamplePartition");

        // Producer的主对象
        Producer<String,String> producer = new KafkaProducer<>(properties);

        // 消息对象 - ProducerRecoder
        for(int i=0;i<5;i++){
            ProducerRecord<String,String> record =
                    new ProducerRecord<>(TOPIC_NAME,"key-"+i,"value-"+i);

            producer.send(record, new Callback() {
                @Override
                public void onCompletion(RecordMetadata recordMetadata, Exception e) {
                    System.out.println(
                            "partition : "+recordMetadata.partition()+" , offset : "+recordMetadata.offset());
                }
            });
        }

        // 所有的通道打开都需要关闭
        producer.close();
    }

    /*
        Producer异步发送带回调函数
     */
    public static void producerSendWithCallback(){
        Properties properties = new Properties();
        properties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,"127.0.0.1:32649");
        properties.put(ProducerConfig.ACKS_CONFIG,"all");
        properties.put(ProducerConfig.RETRIES_CONFIG,"0");
        properties.put(ProducerConfig.BATCH_SIZE_CONFIG,"16384");
        properties.put(ProducerConfig.LINGER_MS_CONFIG,"1");
        properties.put(ProducerConfig.BUFFER_MEMORY_CONFIG,"33554432");

        properties.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG,"org.apache.kafka.common.serialization.StringSerializer");
        properties.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG,"org.apache.kafka.common.serialization.StringSerializer");

        // Producer的主对象
        Producer<String,String> producer = new KafkaProducer<>(properties);

        // 消息对象 - ProducerRecoder
        for(int i=0;i<10;i++){
            ProducerRecord<String,String> record =
                    new ProducerRecord<>(TOPIC_NAME,"key-"+i,"value-"+i);

            producer.send(record, new Callback() {
                @Override
                public void onCompletion(RecordMetadata recordMetadata, Exception e) {
                    System.out.println(
                            "partition : "+recordMetadata.partition()+" , offset : "+recordMetadata.offset());
                }
            });
        }

        // 所有的通道打开都需要关闭
        producer.close();
    }

    /*
        Producer异步发送演示
     */
    public static void producerSend(){
        Properties properties = new Properties();
        properties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,"127.0.0.1:9092");
        properties.put(ProducerConfig.ACKS_CONFIG,"all");
        properties.put(ProducerConfig.RETRIES_CONFIG,"0");
        properties.put(ProducerConfig.BATCH_SIZE_CONFIG,"16384");
        properties.put(ProducerConfig.LINGER_MS_CONFIG,"1");
        properties.put(ProducerConfig.BUFFER_MEMORY_CONFIG,"33554432");

        properties.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG,"org.apache.kafka.common.serialization.StringSerializer");
        properties.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG,"org.apache.kafka.common.serialization.StringSerializer");

        // Producer的主对象
        Producer<String,String> producer = new KafkaProducer<>(properties);

        // 消息对象 - ProducerRecoder
        for(int i=0;i<10;i++){
            ProducerRecord<String,String> record =
                    new ProducerRecord<>(TOPIC_NAME,"key-"+i,"value-"+i);

            producer.send(record);
        }

        // 所有的通道打开都需要关闭
        producer.close();
    }

    /*
        Producer异步阻塞发送
     */
    public static void producerSyncSend() throws ExecutionException, InterruptedException {
        Properties properties = new Properties();
        properties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,"192.168.220.128:9092");
        properties.put(ProducerConfig.ACKS_CONFIG,"all");
        properties.put(ProducerConfig.RETRIES_CONFIG,"0");
        properties.put(ProducerConfig.BATCH_SIZE_CONFIG,"16384");
        properties.put(ProducerConfig.LINGER_MS_CONFIG,"1");
        properties.put(ProducerConfig.BUFFER_MEMORY_CONFIG,"33554432");

        properties.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG,"org.apache.kafka.common.serialization.StringSerializer");
        properties.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG,"org.apache.kafka.common.serialization.StringSerializer");

        // Producer的主对象
        Producer<String,String> producer = new KafkaProducer<>(properties);

        // 消息对象 - ProducerRecoder
        for(int i=0;i<10;i++){
            String key = "key-"+i;
            ProducerRecord<String,String> record =
                    new ProducerRecord<>(TOPIC_NAME,key,"value-"+i);

            Future<RecordMetadata> send = producer.send(record);
            RecordMetadata recordMetadata = send.get();
            System.out.println(key + "partition : "+recordMetadata.partition()+" , offset : "+recordMetadata.offset());
        }

        // 所有的通道打开都需要关闭
        producer.close();
    }

分区策略

public class SamplePartition implements Partitioner {
    @Override
    public int partition(String topic, Object key, byte[] keyBytes, Object value, byte[] valueBytes, Cluster cluster) {
      
      //  String keyStr = key + "";
      //  String keyInt = keyStr.substring(4);
      List<PartitionInfo> partitions = cluster.partitionsForTopic(topic);
      System.out.println("keyStr : "+keyStr + "keyInt : "+keyInt);
      return Math.abs(key.hashCode()) % partitions.size();
       // int i = Integer.parseInt(keyInt);

        return i%2;
    }

    @Override
    public void close() {

    }

    @Override
    public void configure(Map<String, ?> configs) {

    }
}

public class ConsumerSample {/*
        工作里这种用法，有，但是不推荐
     */
    private static void helloworld(){
        Properties props = new Properties();
        props.setProperty("bootstrap.servers", "192.168.220.128:9092");
        props.setProperty("group.id", "test");
        props.setProperty("enable.auto.commit", "true");
        props.setProperty("auto.commit.interval.ms", "1000");
        props.setProperty("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.setProperty("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

        KafkaConsumer<String,String> consumer = new KafkaConsumer(props);
        // 消费订阅哪一个Topic或者几个Topic
        consumer.subscribe(Arrays.asList(TOPIC_NAME));
        while (true) {
            ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(10000));
            for (ConsumerRecord<String, String> record : records)
                System.out.printf("patition = %d , offset = %d, key = %s, value = %s%n",
                        record.partition(),record.offset(), record.key(), record.value());
        }
    }

    /*
        手动提交offset
     */
    private static void commitedOffset() {
        Properties props = new Properties();
        props.setProperty("bootstrap.servers", "192.168.220.128:9092");
        props.setProperty("group.id", "test");
        props.setProperty("enable.auto.commit", "false");
        props.setProperty("auto.commit.interval.ms", "1000");
        props.setProperty("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.setProperty("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

        KafkaConsumer<String, String> consumer = new KafkaConsumer(props);
        // 消费订阅哪一个Topic或者几个Topic
        consumer.subscribe(Arrays.asList(TOPIC_NAME));
        while (true) {
            ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(10000));
            for (ConsumerRecord<String, String> record : records) {
                // 想把数据保存到数据库，成功就成功，不成功...
                // TODO record 2 db
                System.out.printf("patition = %d , offset = %d, key = %s, value = %s%n",
                        record.partition(), record.offset(), record.key(), record.value());
                // 如果失败，则回滚， 不要提交offset
            }

            // 如果成功，手动通知offset提交
            consumer.commitAsync();
        }
    }


    /*
        手动提交offset,并且手动控制partition
     */
    private static void commitedOffsetWithPartition() {
        Properties props = new Properties();
        props.setProperty("bootstrap.servers", "192.168.220.128:9092");
        props.setProperty("group.id", "test");
        props.setProperty("enable.auto.commit", "false");
        props.setProperty("auto.commit.interval.ms", "1000");
        props.setProperty("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.setProperty("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

        KafkaConsumer<String, String> consumer = new KafkaConsumer(props);
        // 消费订阅哪一个Topic或者几个Topic
        consumer.subscribe(Arrays.asList(TOPIC_NAME));
        while (true) {
           ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(10000));
           // 每个partition单独处理
           for(TopicPartition partition : records.partitions()){
               List<ConsumerRecord<String, String>> pRecord = records.records(partition);
               for (ConsumerRecord<String, String> record : pRecord) {
                   System.out.printf("patition = %d , offset = %d, key = %s, value = %s%n",
                           record.partition(), record.offset(), record.key(), record.value());

               }
               long lastOffset = pRecord.get(pRecord.size() -1).offset();
               // 单个partition中的offset，并且进行提交
               Map<TopicPartition, OffsetAndMetadata> offset = new HashMap<>();
               offset.put(partition,new OffsetAndMetadata(lastOffset+1));
               // 提交offset
               consumer.commitSync(offset);
               System.out.println("=============partition - "+ partition +" end================");
           }
        }
    }

    /*
        手动提交offset,并且手动控制partition,更高级
     */
    private static void commitedOffsetWithPartition2() {
        Properties props = new Properties();
        props.setProperty("bootstrap.servers", "192.168.220.128:9092");
        props.setProperty("group.id", "test");
        props.setProperty("enable.auto.commit", "false");
        props.setProperty("auto.commit.interval.ms", "1000");
        props.setProperty("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.setProperty("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

        KafkaConsumer<String, String> consumer = new KafkaConsumer(props);

        // jiangzh-topic - 0,1两个partition
        TopicPartition p0 = new TopicPartition(TOPIC_NAME, 0);
        TopicPartition p1 = new TopicPartition(TOPIC_NAME, 1);

        // 消费订阅哪一个Topic或者几个Topic
//        consumer.subscribe(Arrays.asList(TOPIC_NAME));

        // 消费订阅某个Topic的某个分区
        consumer.assign(Arrays.asList(p0));

        while (true) {
            ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(10000));
            // 每个partition单独处理
            for(TopicPartition partition : records.partitions()){
                List<ConsumerRecord<String, String>> pRecord = records.records(partition);
                for (ConsumerRecord<String, String> record : pRecord) {
                    System.out.printf("patition = %d , offset = %d, key = %s, value = %s%n",
                            record.partition(), record.offset(), record.key(), record.value());

                }
                long lastOffset = pRecord.get(pRecord.size() -1).offset();
                // 单个partition中的offset，并且进行提交
                Map<TopicPartition, OffsetAndMetadata> offset = new HashMap<>();
                offset.put(partition,new OffsetAndMetadata(lastOffset+1));
                // 提交offset
                consumer.commitSync(offset);
                System.out.println("=============partition - "+ partition +" end================");
            }
        }
    }


    /*
        手动指定offset的起始位置，及手动提交offset
     */
    private static void controlOffset() {
        Properties props = new Properties();
        props.setProperty("bootstrap.servers", "192.168.220.128:9092");
        props.setProperty("group.id", "test");
        props.setProperty("enable.auto.commit", "false");
        props.setProperty("auto.commit.interval.ms", "1000");
        props.setProperty("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.setProperty("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

        KafkaConsumer<String, String> consumer = new KafkaConsumer(props);

        // jiangzh-topic - 0,1两个partition
        TopicPartition p0 = new TopicPartition(TOPIC_NAME, 0);

        // 消费订阅某个Topic的某个分区
        consumer.assign(Arrays.asList(p0));

        while (true) {
            // 手动指定offset起始位置
            /*
                1、人为控制offset起始位置
                2、如果出现程序错误，重复消费一次
             */
            /*
                1、第一次从0消费【一般情况】
                2、比如一次消费了100条， offset置为101并且存入Redis
                3、每次poll之前，从redis中获取最新的offset位置
                4、每次从这个位置开始消费
             */
            consumer.seek(p0, 700);

            ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(10000));
            // 每个partition单独处理
            for(TopicPartition partition : records.partitions()){
                List<ConsumerRecord<String, String>> pRecord = records.records(partition);
                for (ConsumerRecord<String, String> record : pRecord) {
                    System.err.printf("patition = %d , offset = %d, key = %s, value = %s%n",
                            record.partition(), record.offset(), record.key(), record.value());

                }
                long lastOffset = pRecord.get(pRecord.size() -1).offset();
                // 单个partition中的offset，并且进行提交
                Map<TopicPartition, OffsetAndMetadata> offset = new HashMap<>();
                offset.put(partition,new OffsetAndMetadata(lastOffset+1));
                // 提交offset
                consumer.commitSync(offset);
                System.out.println("=============partition - "+ partition +" end================");
            }
        }
    }


    /*
        流量控制 - 限流
     */
    private static void controlPause() {
        Properties props = new Properties();
        props.setProperty("bootstrap.servers", "192.168.220.128:9092");
        props.setProperty("group.id", "test");
        props.setProperty("enable.auto.commit", "false");
        props.setProperty("auto.commit.interval.ms", "1000");
        props.setProperty("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.setProperty("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");

        KafkaConsumer<String, String> consumer = new KafkaConsumer(props);

        // jiangzh-topic - 0,1两个partition
        TopicPartition p0 = new TopicPartition(TOPIC_NAME, 0);
        TopicPartition p1 = new TopicPartition(TOPIC_NAME, 1);

        // 消费订阅某个Topic的某个分区
        consumer.assign(Arrays.asList(p0,p1));
        long totalNum = 40;
        while (true) {
            ConsumerRecords<String, String> records = consumer.poll(Duration.ofMillis(10000));
            // 每个partition单独处理
            for(TopicPartition partition : records.partitions()){
                List<ConsumerRecord<String, String>> pRecord = records.records(partition);
                long num = 0;
                for (ConsumerRecord<String, String> record : pRecord) {
                    System.out.printf("patition = %d , offset = %d, key = %s, value = %s%n",
                            record.partition(), record.offset(), record.key(), record.value());
                    /*
                        1、接收到record信息以后，去令牌桶中拿取令牌
                        2、如果获取到令牌，则继续业务处理
                        3、如果获取不到令牌， 则pause等待令牌
                        4、当令牌桶中的令牌足够， 则将consumer置为resume状态
                     */
                    num++;
                    if(record.partition() == 0){
                        if(num >= totalNum){
                            consumer.pause(Arrays.asList(p0));
                        }
                    }

                    if(record.partition() == 1){
                        if(num == 40){
                            consumer.resume(Arrays.asList(p0));
                        }
                    }
                }

                long lastOffset = pRecord.get(pRecord.size() -1).offset();
                // 单个partition中的offset，并且进行提交
                Map<TopicPartition, OffsetAndMetadata> offset = new HashMap<>();
                offset.put(partition,new OffsetAndMetadata(lastOffset+1));
                // 提交offset
                consumer.commitSync(offset);
                System.out.println("=============partition - "+ partition +" end================");
            }
        }
    }

}