Package org.apache.flink.streaming.examples.dsv2.eventtime

Class CountNewsClicks.CountNewsClicksProcessFunction

java.lang.Object

org.apache.flink.streaming.examples.dsv2.eventtime.CountNewsClicks.CountNewsClicksProcessFunction

All Implemented Interfaces:

Serializable, org.apache.flink.api.common.functions.Function, org.apache.flink.datastream.api.extension.eventtime.function.EventTimeProcessFunction, org.apache.flink.datastream.api.extension.eventtime.function.OneInputEventTimeStreamProcessFunction<CountNewsClicks.NewsEvent,CountNewsClicks.NewsClicks>, org.apache.flink.datastream.api.function.OneInputStreamProcessFunction<CountNewsClicks.NewsEvent,CountNewsClicks.NewsClicks>, org.apache.flink.datastream.api.function.ProcessFunction

Enclosing class:

CountNewsClicks

public static class CountNewsClicks.CountNewsClicksProcessFunction
extends Object
implements org.apache.flink.datastream.api.extension.eventtime.function.OneInputEventTimeStreamProcessFunction<CountNewsClicks.NewsEvent,CountNewsClicks.NewsClicks>

This process function will consume CountNewsClicks.NewsEvent and count the number of clicks within 1 hour of the news publication and send the results CountNewsClicks.NewsClicks to the output.

To achieve the goal, we will register an event timer for each news, which will be triggered at the time of the news's release time + 1 hour, and record a click count of each news. In the timer callback onEventTimer, we will output the number of clicks.

To handle the potential disorder between news publication event and click events, we will use a ListState to store the timestamps of click events that occur prior to their corresponding publication events.

To handle the potential missing news publication event, we will register an event timer for the click event and set the timer to the timestamp of the click event plus one hour.

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
CountNewsClicksProcessFunction()

Method Summary

Modifier and Type	Method	Description
void	initEventTimeProcessFunction(org.apache.flink.datastream.api.extension.eventtime.timer.EventTimeManager eventTimeManager)
void	onEventTimer(long timestamp, org.apache.flink.datastream.api.common.Collector<CountNewsClicks.NewsClicks> output, org.apache.flink.datastream.api.context.PartitionedContext<CountNewsClicks.NewsClicks> ctx)
void	processRecord(CountNewsClicks.NewsEvent record, org.apache.flink.datastream.api.common.Collector<CountNewsClicks.NewsClicks> output, org.apache.flink.datastream.api.context.PartitionedContext<CountNewsClicks.NewsClicks> ctx)
Set<org.apache.flink.api.common.state.StateDeclaration>	usesStates()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.flink.datastream.api.extension.eventtime.function.OneInputEventTimeStreamProcessFunction

onEventTimeWatermark

Methods inherited from interface org.apache.flink.datastream.api.function.OneInputStreamProcessFunction

endInput, onProcessingTimer, onWatermark, open

Methods inherited from interface org.apache.flink.datastream.api.function.ProcessFunction

close, declareWatermarks

Constructor Details

CountNewsClicksProcessFunction

public CountNewsClicksProcessFunction()

Method Details

initEventTimeProcessFunction

public void initEventTimeProcessFunction(org.apache.flink.datastream.api.extension.eventtime.timer.EventTimeManager eventTimeManager)

Specified by:

initEventTimeProcessFunction in interface org.apache.flink.datastream.api.extension.eventtime.function.EventTimeProcessFunction

usesStates

public Set<org.apache.flink.api.common.state.StateDeclaration> usesStates()

Specified by:

usesStates in interface org.apache.flink.datastream.api.function.ProcessFunction

processRecord

public void processRecord(CountNewsClicks.NewsEvent record,
 org.apache.flink.datastream.api.common.Collector<CountNewsClicks.NewsClicks> output,
 org.apache.flink.datastream.api.context.PartitionedContext<CountNewsClicks.NewsClicks> ctx)
                   throws Exception

Specified by:

processRecord in interface org.apache.flink.datastream.api.function.OneInputStreamProcessFunction<CountNewsClicks.NewsEvent,CountNewsClicks.NewsClicks>

Throws:

Exception

onEventTimer

public void onEventTimer(long timestamp,
 org.apache.flink.datastream.api.common.Collector<CountNewsClicks.NewsClicks> output,
 org.apache.flink.datastream.api.context.PartitionedContext<CountNewsClicks.NewsClicks> ctx)
                  throws Exception

Specified by:

onEventTimer in interface org.apache.flink.datastream.api.extension.eventtime.function.OneInputEventTimeStreamProcessFunction<CountNewsClicks.NewsEvent,CountNewsClicks.NewsClicks>

Throws:

Exception