com.northconcepts.datapipeline.group

Class CreateWindowStrategy

java.lang.Object

com.northconcepts.datapipeline.group.CreateWindowStrategy

public abstract class CreateWindowStrategy
extends Object

Determines when GroupByReader opens a new sliding window.

Constructor Summary

Constructors

Constructor and Description
CreateWindowStrategy()

Method Summary

Modifier and Type	Method and Description
static CreateWindowStrategy	and(CreateWindowStrategy... strategies) Opens a new window if all of the supplied strategies request it.
boolean	isPollingRequired() Indicates if the {@link #shouldCreate(GroupByReader, Record) method should be called every second -- even if no new data is present -- to allow windows to be created (passing in a null record).
static CreateWindowStrategy	limitOpened(int maxOpenedWindows) Opens a new window if there are less currently open than the specified number.
static CreateWindowStrategy	or(CreateWindowStrategy... strategies) Opens a new window if any of the supplied strategies request it.
static CreateWindowStrategy	recordPeriod(int recordPeriod) Opens a new window at set record count intervals or on the first record.
abstract boolean	shouldCreate(GroupByReader groupByReader, Record record)
static CreateWindowStrategy	startInterval(long intervalMilliseconds) Opens a new window at set time intervals.

Methods inherited from class java.lang.Object

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

Constructor Detail

CreateWindowStrategy

public CreateWindowStrategy()

Method Detail

shouldCreate

public abstract boolean shouldCreate(GroupByReader groupByReader,
                                     Record record)

isPollingRequired

public boolean isPollingRequired()

Indicates if the {@link #shouldCreate(GroupByReader, Record) method should be called every second -- even if no new data is present -- to allow windows to be created (passing in a null record).

limitOpened

public static CreateWindowStrategy limitOpened(int maxOpenedWindows)

Opens a new window if there are less currently open than the specified number.

Parameters:

maxOpenedWindows - the number of widows that should be open at any time.

recordPeriod

public static CreateWindowStrategy recordPeriod(int recordPeriod)

Opens a new window at set record count intervals or on the first record.

Parameters:

recordPeriod - the number of records to wait for before opening a new window.

startInterval

public static CreateWindowStrategy startInterval(long intervalMilliseconds)

Opens a new window at set time intervals.

Parameters:

intervalMilliseconds - the number of milliseconds wait before opening a new window.

or

public static CreateWindowStrategy or(CreateWindowStrategy... strategies)

Opens a new window if any of the supplied strategies request it.

and

public static CreateWindowStrategy and(CreateWindowStrategy... strategies)

Opens a new window if all of the supplied strategies request it.