Flink从集合读取模拟传感器数据-示例

 1、创建传感器实体类

static class SensorReading{
        // 传感器 id
        private String sensorId;
        // 时间戳
        private Long timeStamp;
        // 温度
        private Double temperature;

        public SensorReading(String sensorId,Long timeStamp,Double temperature){
            this.sensorId = sensorId;
            this.timeStamp = timeStamp;
            this.temperature = temperature;
        }

        @Override
        public String toString() {
            return "SensorReading{" +
                    "sensorId='" + sensorId + '\'' +
                    ", timeStamp=" + timeStamp +
                    ", temperature=" + temperature +
                    '}';
        }

2、模拟传感器数据

public static List getSensorList(){
        // 模拟传感器数据
        List list = new ArrayList<SensorReading>();
        list.add(new SensorReading("1",1608112731l,35.5));
        list.add(new SensorReading("2",1608112830l,35.6));
        list.add(new SensorReading("3",1608112837l,35.5));
        list.add(new SensorReading("4",1608112842l,35.7));
        list.add(new SensorReading("5",1608112851l,35.8));
        return list;
    }

3、使用 fromCollection 方法读取数据，并展示控制台

public static void main(String[] args) throws Exception {
        // 创建流处理的执行环境
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

        //使用StreamExecutionEnvironment创建DataStream
        // Source数据源为集合，从getSensorList方法中获取
        DataStreamSource<SensorReading> stream1 = env.fromCollection(getSensorList());

        // 调用Sink
        stream1.print("stream1:").setParallelism(1);

        // 启动任务执行
        env.execute();
    }

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