企石网站建设,网站域名选择的原则,app开发公司怎么赚钱的,做美食网站的背景一、说明
基于处理时间或者事件时间处理过一个元素之后, 注册一个定时器, 然后指定的时间执行. Context和OnTimerContext所持有的TimerService对象拥有以下方法: currentProcessingTime(): Long 返回当前处理时间 currentWatermark(): Long 返回当前watermark的时间戳 registe…一、说明
基于处理时间或者事件时间处理过一个元素之后, 注册一个定时器, 然后指定的时间执行. Context和OnTimerContext所持有的TimerService对象拥有以下方法: currentProcessingTime(): Long 返回当前处理时间 currentWatermark(): Long 返回当前watermark的时间戳 registerProcessingTimeTimer(timestamp: Long): Unit 会注册当前key的processing time的定时器。当processing time到达定时时间时触发timer。 registerEventTimeTimer(timestamp: Long): Unit 会注册当前key的event time 定时器。当水位线大于等于定时器注册的时间时触发定时器执行回调函数。 deleteProcessingTimeTimer(timestamp: Long): Unit 删除之前注册处理时间定时器。如果没有这个时间戳的定时器则不执行。 deleteEventTimeTimer(timestamp: Long): Unit 删除之前注册的事件时间定时器如果没有此时间戳的定时器则不执行。
二、基于处理时间的定时器
package com.lyh.flink08;import com.lyh.bean.WaterSensor;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.KeyedProcessFunction;
import org.apache.flink.util.Collector;public class ProcessTime {public static void main(String[] args) throws Exception {StreamExecutionEnvironment env StreamExecutionEnvironment.getExecutionEnvironment();env.setParallelism(1);SingleOutputStreamOperatorWaterSensor stream env.socketTextStream(hadoop100, 9999).map(line - {String[] datas line.split(,);return new WaterSensor(datas[0],Long.valueOf(datas[1]),Integer.valueOf(datas[2]));});stream.keyBy(WaterSensor::getId).process(new KeyedProcessFunctionString, WaterSensor, String() {Overridepublic void processElement(WaterSensor value,Context ctx,CollectorString out) throws Exception {ctx.timerService().registerProcessingTimeTimer(ctx.timerService().currentProcessingTime() 5000);out.collect(value.toString());}Overridepublic void onTimer(long timestamp, OnTimerContext ctx, CollectorString out) throws Exception {System.out.println(timestamp);out.collect(wo be chu fa le );}}).print();env.execute();}
}三、基于事件时间的定时器
package com.lyh.flink08;import com.lyh.bean.WaterSensor;
import org.apache.flink.api.common.eventtime.WatermarkStrategy;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.KeyedProcessFunction;
import org.apache.flink.util.Collector;import java.time.Duration;public class EventTime_s {public static void main(String[] args) throws Exception {StreamExecutionEnvironment env StreamExecutionEnvironment.getExecutionEnvironment();env.setParallelism(1);SingleOutputStreamOperatorWaterSensor stream env.socketTextStream(hadoop100, 9999).map(line - {String[] datas line.split(,);return new WaterSensor(datas[0],Long.valueOf(datas[1]),Integer.valueOf(datas[2]));});WatermarkStrategyWaterSensor wms WatermarkStrategy.WaterSensorforBoundedOutOfOrderness(Duration.ofSeconds(3)).withTimestampAssigner((element,recordTimestamp) - element.getTs() * 1000);stream.assignTimestampsAndWatermarks(wms).keyBy(WaterSensor::getId).process(new KeyedProcessFunctionString, WaterSensor, String() {Overridepublic void processElement(WaterSensor value,Context ctx,CollectorString out) throws Exception {System.out.println(ctx.timestamp());ctx.timerService().registerProcessingTimeTimer(ctx.timestamp()5000);out.collect(value.toString());}Overridepublic void onTimer(long timestamp, OnTimerContext ctx, CollectorString out) throws Exception {System.out.println(定时器被触发了);}}).print();env.execute();}
}
