jstorm系列-2：入门

有了基本的概念之后，我们用jstorm来做一点小事情吧

做一个很无聊的事情：给定一个时间戳，输出对应的问候语

规则是：时间戳的十位对应的数字对应不同的时间段，0-2代表早上，3代表中午，4-6代表下午，7-9代表晚上，分别输出早上，中午，下午和晚上。

我们用spout来发送时间戳，bolt来处理时间戳并输出对应的问候语，并且统计每一时间段的问候数目，判断时间戳的生成是否随机。

代码如下：

public class TimeStampSpout implements IRichSpout{
private static final long serialVersionUID = 1L;
private SpoutOutputCollector collector;

@Override
　　　　。。。。一切没有用到的函数不展示

@Override
public void nextTuple() {
long now = System.currentTimeMillis();
Values tuple = new Values(now);
System.out.println("spout:"+tuple);
this.collector.emit(tuple);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}

@Override
public void open(Map conf, TopologyContext context, SpoutOutputCollector collector) {
this.collector = collector;
}

@Override
public void declareOutputFields(OutputFieldsDeclarer declarer) {
declarer.declare(new Fields("timestamp"));
}

}

public class GreetingBolt implements IRichBolt{
private static final long serialVersionUID = 1L;
private static Map<String, Integer> count = new TreeMap<String, Integer>();
private final String morning = "morning";
private final String noon = "noon";
private final String afternoon = "afternoon";
private final String evening = "evening";
private static Integer total = 0;
@Override
public void cleanup() {
}

@Override
public void execute(Tuple input) {
long timestamp= input.getLong(0);
//        System.out.println("bolt:"+timestamp);
total+=1;
//        获取十位数
long second = (timestamp/10)%10;
if(second<3){
System.out.println("bolt:"+morning);
count.put(morning, (count.get(morning)==null)?1:count.get(morning)+1);
}
else if(second==3){
System.out.println("bolt:"+noon);
count.put(noon, (count.get(noon)==null)?1:count.get(noon)+1);
}
else if(second<8){
System.out.println("bolt:"+afternoon);
count.put(afternoon, (count.get(afternoon)==null)?1:count.get(afternoon)+1);
}
else{
System.out.println("bolt:"+evening);
count.put(evening, (count.get(evening)==null?1:count.get(evening)+1));
}
if(total%10==0){
System.out.println("distribution show as followed:");
System.out.println(morning+":"+1.0*((count.get(morning)==null)?0:count.get(morning))/total);
System.out.println(noon+":"+1.0*((count.get(noon)==null?0:count.get(noon)))/total);
System.out.println(afternoon+":"+1.0*((count.get(afternoon)==null?0:count.get(afternoon)))/total);
System.out.println(evening+":"+1.0*((count.get(evening)==null?0:count.get(evening)))/total);
}
}

}

public class TestTopology {
public static void main(String[] args) {
TopologyBuilder builder = new TopologyBuilder();
builder.setSpout("TimeStampSpout", new TimeStampSpout());
builder.setBolt("GreetingBolt",new Gre
7ff7
etingBolt()).shuffleGrouping("TimeStampSpout");
LocalCluster cluster = new LocalCluster();
Config config = new Config();
cluster.submitTopology("test", config, builder.createTopology());
}
}

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转载于:https://www.cnblogs.com/qwj-sysu/p/5172005.html