Package com.helger.commons.concurrent.collector

Class ConcurrentCollectorSingle<DATATYPE>

java.lang.Object

com.helger.commons.concurrent.collector.AbstractConcurrentCollector<DATATYPE>

com.helger.commons.concurrent.collector.ConcurrentCollectorSingle<DATATYPE>

Type Parameters:

DATATYPE - The type of the objects in the queue.

All Implemented Interfaces:

IConcurrentCollector, IMutableConcurrentCollector<DATATYPE>

public class ConcurrentCollectorSingle<DATATYPE>
extends AbstractConcurrentCollector<DATATYPE>

Concurrent collector that performs action on each object separately

Author:

Philip Helger

Field Summary

Fields inherited from class com.helger.commons.concurrent.collector.AbstractConcurrentCollector

DEFAULT_MAX_QUEUE_SIZE, m_aQueue, STOP_QUEUE_OBJECT

Constructor Summary

Constructors

Constructor	Description
ConcurrentCollectorSingle()	Constructor that uses AbstractConcurrentCollector.DEFAULT_MAX_QUEUE_SIZE elements as the maximum queue length.
ConcurrentCollectorSingle(int nMaxQueueSize)	Constructor.
ConcurrentCollectorSingle(BlockingQueue<Object> aQueue)	Constructor using an existing BlockingQueue.

Method Summary

Modifier and Type	Method	Description
void	collect()	This method starts the collector by taking objects from the internal BlockingQueue.
IConcurrentPerformer<DATATYPE>	getPerformer()
ConcurrentCollectorSingle<DATATYPE>	setPerformer(IConcurrentPerformer<DATATYPE> aPerformer)	Set the performer to be used.

Methods inherited from class com.helger.commons.concurrent.collector.AbstractConcurrentCollector

drainQueue, getQueueLength, isQueueEmpty, isStopped, queueObject, stopQueuingNewObjects

Methods inherited from class java.lang.Object

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

Constructor Detail

ConcurrentCollectorSingle

public ConcurrentCollectorSingle()

Constructor that uses AbstractConcurrentCollector.DEFAULT_MAX_QUEUE_SIZE elements as the maximum queue length.

ConcurrentCollectorSingle

public ConcurrentCollectorSingle(@Nonnegative
                                 int nMaxQueueSize)

Constructor.

Parameters:

nMaxQueueSize - The maximum number of items that can be in the queue. Must be > 0.

ConcurrentCollectorSingle

public ConcurrentCollectorSingle(@Nonnull
                                 BlockingQueue<Object> aQueue)

Constructor using an existing BlockingQueue.

Parameters:

aQueue - BlockingQueue to use. May not be null.

Method Detail

getPerformer

@Nullable
public final IConcurrentPerformer<DATATYPE> getPerformer()

Returns:

The current performer set. null if none was explicitly set.

setPerformer

@Nonnull
public final ConcurrentCollectorSingle<DATATYPE> setPerformer(@Nonnull
                                                              IConcurrentPerformer<DATATYPE> aPerformer)

Set the performer to be used. This method must be invoked before the collector can be run. The passed implementation must be rock-solid as this class will not make any retries. If the passed performer throws and exception without handling the objects correct the objects will be lost!

Parameters:

aPerformer - The performer to be used. May not be null.

Returns:

this for chaining

Throws:

IllegalStateException - If another performer is already present!

collect

public final void collect()

This method starts the collector by taking objects from the internal BlockingQueue. So this method blocks and must be invoked from a separate thread. This method runs until AbstractConcurrentCollector.stopQueuingNewObjects() is new called and the queue is empty.

Throws:

IllegalStateException - if no performer is set - see setPerformer(IConcurrentPerformer)