- 建立maven工程,pom.xml中增加如下:
- <dependency>
- <groupId>org.apache.kafka</groupId>
- <artifactId>kafka_2.10</artifactId>
- <version>0.8.2.0</version>
- </dependency>
- 2 java代碼: 向主題test内寫入資料
- import java.util.Properties;
- import java.util.concurrent.TimeUnit;
- import kafka.javaapi.producer.Producer;
- import kafka.producer.KeyedMessage;
- import kafka.producer.ProducerConfig;
- import kafka.serializer.StringEncoder;
- public class kafkaProducer extends Thread{
- private String topic;
- public kafkaProducer(String topic){
- super();
- this.topic = topic;
- }
- @Override
- public void run() {
- Producer producer = createProducer();
- int i=0;
- while(true){
- producer.send(new KeyedMessage<Integer, String>(topic, "message: " + i++));
- try {
- TimeUnit.SECONDS.sleep(1);
- } catch (InterruptedException e) {
- e.printStackTrace();
- }
- }
- }
- private Producer createProducer() {
- Properties properties = new Properties();
- properties.put("zookeeper.connect", "192.168.1.110:2181,192.168.1.111:2181,192.168.1.112:2181");//聲明zk
- properties.put("serializer.class", StringEncoder.class.getName());
- properties.put("metadata.broker.list", "192.168.1.110:9092,192.168.1.111:9093,192.168.1.112:9094");// 聲明kafka broker
- return new Producer<Integer, String>(new ProducerConfig(properties));
- }
- public static void main(String[] args) {
- new kafkaProducer("test").start();// 使用kafka叢集中建立好的主題 test
- }
- }
- 3 kafka叢集中消費主題test的資料:
- [root@h2master kafka]# bin/kafka-console-consumer.sh --zookeeper localhost:2181 --topic test --from-beginnin
- 4 啟動java代碼,然後在看叢集消費的資料如下:
- message: 0
- message: 1
- message: 2
- message: 3
- message: 4
- message: 5
- message: 6
- message: 7
- message: 8
- message: 9
- message: 10
- message: 11
- message: 12
- message: 13
- message: 14
- message: 15
- message: 16
- message: 17
- message: 18
- message: 19
- message: 20
- message: 21
3 kafka 使用Java寫消費者,這樣 先運作kafkaProducer ,在運作kafkaConsumer,即可得到生産者的資料:
Java代碼
- import java.util.HashMap;
- import java.util.List;
- import java.util.Map;
- import java.util.Properties;
- import kafka.consumer.Consumer;
- import kafka.consumer.ConsumerConfig;
- import kafka.consumer.ConsumerIterator;
- import kafka.consumer.KafkaStream;
- import kafka.javaapi.consumer.ConsumerConnector;
- public class kafkaConsumer extends Thread{
- private String topic;
- public kafkaConsumer(String topic){
- super();
- this.topic = topic;
- }
- @Override
- public void run() {
- ConsumerConnector consumer = createConsumer();
- Map<String, Integer> topicCountMap = new HashMap<String, Integer>();
- topicCountMap.put(topic, 1); // 一次從主題中擷取一個資料
- Map<String, List<KafkaStream<byte[], byte[]>>> messageStreams = consumer.createMessageStreams(topicCountMap);
- KafkaStream<byte[], byte[]> stream = messageStreams.get(topic).get(0);// 擷取每次接收到的這個資料
- ConsumerIterator<byte[], byte[]> iterator = stream.iterator();
- while(iterator.hasNext()){
- String message = new String(iterator.next().message());
- System.out.println("接收到: " + message);
- }
- }
- private ConsumerConnector createConsumer() {
- Properties properties = new Properties();
- properties.put("zookeeper.connect", "192.168.1.110:2181,192.168.1.111:2181,192.168.1.112:2181");//聲明zk
- properties.put("group.id", "group1");// 必須要使用别的組名稱, 如果生産者和消費者都在同一組,則不能通路同一組内的topic資料
- return Consumer.createJavaConsumerConnector(new ConsumerConfig(properties));
- }
- public static void main(String[] args) {
- new kafkaConsumer("test").start();// 使用kafka叢集中建立好的主題 test
- }
- }