com.github.triceo.splitlog.api

Interface MessageMetric<T extends Number,S extends MessageProducer<S>>

Type Parameters:

T - Type of the value that the metric is measuring.

S - Where this is getting its Messages from.

All Superinterfaces:

MessageConsumer<S>, MessageListener<S>

public interface MessageMetric<T extends Number,S extends MessageProducer<S>>
extends MessageConsumer<S>

Allows users to track various statistics on classes implementing MessageProducer. These classes are intended for measuring only, and will therefore not store the Messages that have passed through them.

Method Summary

Methods

Modifier and Type	Method and Description
Future<Message>	expect(C condition) Will return a future that will only return when a message arrives that makes the given condition return true.
Future<Message>	expect(C condition, MessageAction<S> action) Will return a future that will only return when a message arrives that makes the given condition return true, at which point it asynchronously executes a particular action.
MessageMeasure<T,S>	getMeasure() Retrieves the measure that is used to produce the value of this metric.
long	getMessageCount() Retrieve the number of times that the metric has been invoked on a Message.
long	getMessageCount(Message timestamp) Retrieve the number of times that the metric has been invoked on a Message, at the time immediately after a given message has been processed.
S	getSource() Retrieve the instance that is responsible for notifying this metric of new Messages-
T	getValue() Retrieve the value of this metric, which is a sum of the return values of all of this metric's MessageMeasure invocations.
T	getValue(Message timestamp) Retrieve the value of this metric, which is a sum of the return values of all of this metric's MessageMeasure invocations, at the time immediately after a given message has been processed.
Message	waitFor(C condition) Deprecated.
Message	waitFor(C condition, long timeout, TimeUnit unit) Deprecated.

Methods inherited from interface com.github.triceo.splitlog.api.MessageConsumer

isStopped, stop

Methods inherited from interface com.github.triceo.splitlog.api.MessageListener

messageReceived

Method Detail

getMeasure

MessageMeasure<T,S> getMeasure()

Retrieves the measure that is used to produce the value of this metric.

Returns:

Never null.

getMessageCount

long getMessageCount()

Retrieve the number of times that the metric has been invoked on a Message.

Returns:

A number >= 0.

getMessageCount

long getMessageCount(Message timestamp)

Retrieve the number of times that the metric has been invoked on a Message, at the time immediately after a given message has been processed.

Parameters:

timestamp - The point in time after this message was processed.

Returns:

0 when timestamp is null. -1 in case no such message was ever processed by this metric. The proper value otherwise.

getSource

S getSource()

Retrieve the instance that is responsible for notifying this metric of new Messages-

Returns:

Typically the instance that was used to retrieve this metric.

getValue

T getValue()

Retrieve the value of this metric, which is a sum of the return values of all of this metric's MessageMeasure invocations.

Returns:

Whatever, depends on the measure. Initial value, before any messages arrive, is null

getValue

T getValue(Message timestamp)

Retrieve the value of this metric, which is a sum of the return values of all of this metric's MessageMeasure invocations, at the time immediately after a given message has been processed.

Parameters:

timestamp - The point in time after this message was processed. Null will retrieve the initial state.

Returns:

Whatever, depends on the measure. Initial state, before any messages arrive, is MessageMeasure.initialValue(). Null is returned in case no such message was ever processed by this metric.

expect

Future<Message> expect(C condition)

Will return a future that will only return when a message arrives that makes the given condition return true.

Parameters:

condition - Condition that needs to be true for the future to unblock.

Returns:

Null if the method unblocked due to some other reason.

Throws:

IllegalStateException - When already #isStopped().

expect

Future<Message> expect(C condition,
                     MessageAction<S> action)

Will return a future that will only return when a message arrives that makes the given condition return true, at which point it asynchronously executes a particular action. It will not return until that action has finished executing.

Parameters:

condition - Condition that needs to be true for the future to unblock.

action - Action to execute when the condition becomes true.

Returns:

Null if the method unblocked due to some other reason.

Throws:

IllegalStateException - When already #isStopped().

waitFor

@Deprecated
Message waitFor(C condition)

Deprecated.

Will block until a message arrives, for which the condition is true.

Parameters:

condition - Condition that needs to be true for the method to unblock.

Returns:

Null if the method unblocked due to some other reason.

Throws:

IllegalStateException - When already #isStopped().

waitFor

@Deprecated
Message waitFor(C condition,
                         long timeout,
                         TimeUnit unit)

Deprecated.

Will block until a message arrives, for which the condition is true. If none arrives before the timeout, it unblocks anyway.

Parameters:

condition - Condition that needs to be true for the method to unblock.

timeout - Time before forcibly aborting.

unit - Unit of time.

Returns:

Null if the method unblocked due to some other reason.

Throws:

IllegalStateException - When already #isStopped().