org.apache.nifi.cluster.event.impl

Class EventManagerImpl

java.lang.Object

org.apache.nifi.cluster.event.impl.EventManagerImpl

All Implemented Interfaces:

EventManager

public class EventManagerImpl
extends Object
implements EventManager

Implements the EventManager.

Field Summary

Fields

Modifier and Type	Field and Description
private int	eventHistorySize the number of events to maintain for a given source
private Map<String,Queue<Event>>	eventsMap associates the source ID with an ordered queue of events, ordered by most recent event

Constructor Summary

Constructors

Constructor and Description
EventManagerImpl(int eventHistorySize) Creates an instance.

Method Summary

Methods

Modifier and Type	Method and Description
void	addEvent(Event event) Adds an event to the manager.
void	clearEventHistory(String eventSource)
private Comparator	createEventComparator()
int	getEventHistorySize() Returns the history size.
List<Event>	getEvents(String eventSource) Returns a list of events for a given source sorted by the event's timestamp where the most recent event is first in the list.
Event	getMostRecentEvent(String eventSource)
private void	removeOldestEvent(Collection<Event> events)

Methods inherited from class java.lang.Object

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

Field Detail

eventsMap

private final Map<String,Queue<Event>> eventsMap

associates the source ID with an ordered queue of events, ordered by most recent event

eventHistorySize

private final int eventHistorySize

the number of events to maintain for a given source

Constructor Detail

EventManagerImpl

public EventManagerImpl(int eventHistorySize)

Creates an instance.

Parameters:

eventHistorySize - the number of events to manage for a given source. Value must be positive.

Method Detail

addEvent

public void addEvent(Event event)

Description copied from interface: EventManager

Adds an event to the manager.

Specified by:

addEvent in interface EventManager

Parameters:

event - an Event

getEvents

public List<Event> getEvents(String eventSource)

Description copied from interface: EventManager

Returns a list of events for a given source sorted by the event's timestamp where the most recent event is first in the list.

Specified by:

getEvents in interface EventManager

Parameters:

eventSource - the source

Returns:

the list of events

getEventHistorySize

public int getEventHistorySize()

Description copied from interface: EventManager

Returns the history size.

Specified by:

getEventHistorySize in interface EventManager

Returns:

the history size

getMostRecentEvent

public Event getMostRecentEvent(String eventSource)

Specified by:

getMostRecentEvent in interface EventManager

clearEventHistory

public void clearEventHistory(String eventSource)

Specified by:

clearEventHistory in interface EventManager

createEventComparator

private Comparator createEventComparator()

removeOldestEvent

private void removeOldestEvent(Collection<Event> events)