com.amazonaws.services.kinesis.metrics.impl

Class MetricAccumulatingQueue<KeyType>

java.lang.Object

com.amazonaws.services.kinesis.metrics.impl.MetricAccumulatingQueue<KeyType>

Type Parameters:

KeyType - can be a class or object defined by the user that stores information about a MetricDatum needed by the user. The following is a example of what a KeyType class might look like: class SampleKeyType { private long timeKeyCreated; private MetricDatum datum; public SampleKeyType(long timeKeyCreated, MetricDatum datum){ this.timeKeyCreated = timeKeyCreated; this.datum = datum; } }

public class MetricAccumulatingQueue<KeyType>
extends Object

Helper class for accumulating MetricDatums with the same name and dimensions.

Constructor Summary

Constructors

Constructor and Description
MetricAccumulatingQueue(int maxQueueSize)

Method Summary

Modifier and Type	Method and Description
List<MetricDatumWithKey<KeyType>>	drain(int maxItems)
boolean	isEmpty()
boolean	offer(KeyType key, MetricDatum datum) We use a queue and a map in this method.
int	size()

Methods inherited from class java.lang.Object

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

Constructor Detail

MetricAccumulatingQueue

public MetricAccumulatingQueue(int maxQueueSize)

Method Detail

drain

public List<MetricDatumWithKey<KeyType>> drain(int maxItems)

Parameters:

maxItems - number of items to remove from the queue.

Returns:

a list of MetricDatums that are no longer contained within the queue or map.

isEmpty

public boolean isEmpty()

size

public int size()

offer

public boolean offer(KeyType key,
                     MetricDatum datum)

We use a queue and a map in this method. The reason for this is because, the queue will keep our metrics in FIFO order and the map will provide us with constant time lookup to get the appropriate MetricDatum.

Parameters:

key - metric key to be inserted into queue

datum - metric to be inserted into queue

Returns:

a boolean depending on whether the datum was inserted into the queue