com.github.triceo.splitlog.api

Interface MessageProducer<P extends MessageProducer<P>>

Type Parameters:

P - Where this is getting its Messages from.

All Known Subinterfaces:

CommonFollower<P,C>, Follower, LogWatch, MergingFollower

public interface MessageProducer<P extends MessageProducer<P>>

Implementors of this interface provide users with means of measuring various properties of Messages that pass through them.

Method Summary

Modifier and Type	Method and Description
int	countConsumers() Return the number of consumers that have been startConsuming(MessageListener)'d and not stopConsuming(MessageConsumer)'d.
int	countMetrics() Return the number of metrics that have been startMeasuring(MessageMeasure, String)'d and not stopMeasuring(String)'d.
MessageMetric<? extends Number,P>	getMetric(String id) Retrieve the metric for a particular ID.
String	getMetricId(MessageMetric<? extends Number,P> measure) Retrieve the ID for a particular measure.
boolean	isConsuming(MessageConsumer<P> consumer) Whether or not the particular message consumer is being notified of new messages.
boolean	isMeasuring(MessageMetric<? extends Number,P> metric) Whether or not particular MessageMetric is active.
boolean	isMeasuring(String id) Whether or not particular MessageMetric is active.
MessageConsumer<P>	startConsuming(MessageListener<P> listener) Register a listener to be notified of new messages in this producer.
<T extends Number> MessageMetric<T,P>	startMeasuring(MessageMeasure<T,P> measure, String id) Request that a message property be tracked from now on.
boolean	stopConsuming(MessageConsumer<P> consumer) Tell a consumer to no longer listen to new messages in this producer.
boolean	stopMeasuring(MessageMetric<? extends Number,P> metric) Will stop the metric from being notified of new Messages.
boolean	stopMeasuring(String id) Will stop the metric from being notified of new Messages.

Method Detail

countConsumers

int countConsumers()

Return the number of consumers that have been startConsuming(MessageListener)'d and not stopConsuming(MessageConsumer)'d.

Returns:

Always 0 or more.

countMetrics

int countMetrics()

Return the number of metrics that have been startMeasuring(MessageMeasure, String)'d and not stopMeasuring(String)'d.

Returns:

Always 0 or more.

getMetric

MessageMetric<? extends Number,P> getMetric(String id)

Retrieve the metric for a particular ID.

Parameters:

id - The ID under which the metric has been requested in startMeasuring(MessageMeasure, String).

Returns:

Null if no such metric. Either not startMeasuring(MessageMeasure, String)'d or already stopMeasuring(MessageMetric)'d.

getMetricId

String getMetricId(MessageMetric<? extends Number,P> measure)

Retrieve the ID for a particular measure.

Parameters:

measure - The metric retrieved by startMeasuring(MessageMeasure, String).

Returns:

Null if no such metric. Either not startMeasuring(MessageMeasure, String)'d or already stopMeasuring(MessageMetric)'d.

isConsuming

boolean isConsuming(MessageConsumer<P> consumer)

Whether or not the particular message consumer is being notified of new messages.

Parameters:

consumer - Consumer in question.

Returns:

True if called between startConsuming(MessageListener) and stopConsuming(MessageConsumer).

isMeasuring

boolean isMeasuring(MessageMetric<? extends Number,P> metric)

Whether or not particular MessageMetric is active.

Parameters:

metric - Metric in question.

Returns:

True after startMeasuring(MessageMeasure, String) has been called and before stopMeasuring(MessageMetric).

isMeasuring

boolean isMeasuring(String id)

Whether or not particular MessageMetric is active.

Parameters:

id - ID of the metric in question.

Returns:

True after startMeasuring(MessageMeasure, String) has been called and before stopMeasuring(String).

startConsuming

MessageConsumer<P> startConsuming(MessageListener<P> listener)

Register a listener to be notified of new messages in this producer.

Parameters:

listener - Listener in question.

Returns:

A newly produced consumer in case the listener is submitted for the first time, the original consumer instance in case the listener is submitted repeatedly.

Throws:

IllegalArgumentException - When listener instanceof MessageConsumer .

startMeasuring

<T extends Number> MessageMetric<T,P> startMeasuring(MessageMeasure<T,P> measure,
                                                     String id)

Request that a message property be tracked from now on.

Type Parameters:

T - The numeric type to be measured.

Parameters:

measure - The class that measures the given property. It is highly recommended that a measure instance be exclusive to each metric.

id - Unique identifier by which to locate the metric later.

Returns:

The metric to query for the value of the given property.

Throws:

IllegalArgumentException - When a given ID has already been passed to startMeasuring(MessageMeasure, String) and not to stopMeasuring(String) or equivalents.

stopConsuming

boolean stopConsuming(MessageConsumer<P> consumer)

Tell a consumer to no longer listen to new messages in this producer.

Parameters:

consumer - Consumer in question.

Returns:

True, unless no longer isConsuming(MessageConsumer).

stopMeasuring

boolean stopMeasuring(MessageMetric<? extends Number,P> metric)

Will stop the metric from being notified of new Messages. From this point on, the ID will become available for taking.

Parameters:

metric - The metric in question.

Returns:

True if stopped, false if unknown.

stopMeasuring

boolean stopMeasuring(String id)

Will stop the metric from being notified of new Messages. From this point on, the ID will become available for taking.

Parameters:

id - ID of the metric in question.

Returns:

True if stopped, false if unknown.