练习 ： Flink 自定义Process_State 使用 OnTimer 连续3s大于70度 传感器报警

package ontime;

import com.Sensor;
import org.apache.flink.api.common.state.ValueState;
import org.apache.flink.api.common.state.ValueStateDescriptor;
import org.apache.flink.api.java.tuple.Tuple;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.functions.KeyedProcessFunction;
import org.apache.flink.util.Collector;

public class MyProcess extends KeyedProcessFunction<Tuple, Sensor,String> {

    ValueState<Double> tempState;
    ValueState<Long> timeState;
    private Integer tempInterval;
    public MyProcess(Integer tempInterval){
        this.tempInterval=tempInterval;
    }

    @Override
    public void open(Configuration parameters) throws Exception {
        tempState=getRuntimeContext().getState(new ValueStateDescriptor<Double>("last-temp",Double.class));
        timeState=getRuntimeContext().getState(new ValueStateDescriptor<Long>("last-time",Long.class));

    }

    @Override
    public void processElement(Sensor sensor, Context context, Collector<String> collector) throws Exception {
        Double lastTemp = tempState.value();
        Long lastTime = timeState.value();
        if (sensor.getSensorTemp()>70 && lastTime==null){
            long times = context.timerService().currentProcessingTime() + tempInterval * 1000L;
            context.timerService().registerProcessingTimeTimer(times);
            timeState.update(times);
        }else if (sensor.getSensorTemp()<70 && lastTime!=null ) {
            context.timerService().deleteProcessingTimeTimer(lastTime);
            timeState.clear();
        }
        tempState.update(sensor.getSensorTemp());

    }

    @Override
    public void onTimer(long timestamp, OnTimerContext ctx, Collector<String> out) throws Exception {
        System.out.println("sensor:"+ctx.getCurrentKey().getField(0)+"温度连续3秒大于70度");
    }

    @Override
    public void close() throws Exception {
        timeState.clear();
    }
}

package ontime;

import com.MySource;
import com.Sensor;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;

//StateTest
public class StateTest {
    public static void main(String[] args) throws Exception {
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        //并行度
        env.setParallelism(1);
        //自定义数据源 生成70度左右的传感器数据
        DataStreamSource<Sensor> source = env.addSource(new MySource(70));
        //打印
        source.print();
        //自定义process 3s间隔
        SingleOutputStreamOperator<String> out = source.keyBy("sensorId").process(new MyProcess(3));
        //报警
        out.print();
        //执行
        env.execute();
    }
}