开启线程的多个方式

1. 开启多个线程

1. new 之后通过start
2. 或者在重写方法之后(例如:afterPropertiesSet),进行start

          int numThreads = 5;
          if (numThreads < 1 || numThreads > 5) {
              log.error("NUM_THREADS is out of range");
              System.exit(-1);
          }
          ToDoInfConsumer[] toDoInfConsumers = new ToDoInfConsumer[numThreads];
          for (int i = 0; i < toDoInfConsumers.length; i++) {
            //这有多例,所以注解的时候需要将要生成的consumer设置成多例@Scope("prototype")
              toDoInfConsumers[i] = applicationContext.getBean(ToDoInfConsumer.class);
          }
          for (ToDoInfConsumer toDoInfConsumer : toDoInfConsumers) {
              toDoInfConsumer.start();
          }
          

设置完属性之后,开启线程,要继承initialize bean

//注意继承initialize bean 
public class BalanceStatusConsumer extends Thread implements InitializingBean{}

    //在注入的时候,就会生自动运行run命令
    public BalanceStatusConsumer() {
        try {
            Properties prop = new Properties();
            String addrs = BalStsUtil.KAFKA_SERVERS;
            String groupId = BalStsUtil.KAFKA_GROUPID;
            prop.setProperty("bootstrap.servers", addrs);
            prop.setProperty("group.id", groupId);
            prop.setProperty("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
            prop.setProperty("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
            prop.setProperty("enable.auto.commit", "false");
            prop.setProperty("auto.offset.reset", "latest");
            prop.put("session.timeout.ms", "50000");
            prop.put("request.timeout.ms", "60000");
            prop.put("max.poll.records", "50");
            consumer = new KafkaConsumer<String, String>(prop);
        } catch (Exception e) {
            log.error("Initial Consumer fail: " + e);
        }
    }

    //开启线程
    @Override
    public void afterPropertiesSet() throws Exception {
        start();
    }

2. 设置环境变量

numThreads = Integer.parseInt(System.getenv("NUM_THREADS"));

run configration --> environment

注意

默认spring中的对象都是单例的,如果要多例需要用户自己设置