com.netflix.servo.publish

Class AsyncMetricObserver

java.lang.Object

com.netflix.servo.publish.BaseMetricObserver

com.netflix.servo.publish.AsyncMetricObserver

All Implemented Interfaces:

MetricObserver

public final class AsyncMetricObserver
extends BaseMetricObserver

Wraps another observer and asynchronously updates it in the background. The update call will always return immediately. If the queue fills up newer updates will overwrite older updates.

If an exception is thrown when calling update on wrapped observer it will be logged, but otherwise ignored.

Constructor Summary

Constructors

Constructor and Description
AsyncMetricObserver(java.lang.String name, MetricObserver observer) Creates a new instance with an unbounded queue and no expiration time.
AsyncMetricObserver(java.lang.String name, MetricObserver observer, int queueSize) Creates a new instance with no expiration time.
AsyncMetricObserver(java.lang.String name, MetricObserver observer, int queueSize, long expireTime) Creates a new instance.

Method Summary

Modifier and Type	Method and Description
void	stop() Stop the background thread that pushes updates to the wrapped observer.
void	updateImpl(java.util.List<Metric> metrics) Update method that should be defined by sub-classes.

Methods inherited from class com.netflix.servo.publish.BaseMetricObserver

getFailedUpdateCount, getName, getUpdateCount, incrementFailedCount, update

Methods inherited from class java.lang.Object

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

Constructor Detail

AsyncMetricObserver

public AsyncMetricObserver(java.lang.String name,
                           MetricObserver observer,
                           int queueSize,
                           long expireTime)

Creates a new instance.

Parameters:

name - name of this observer

observer - a wrapped observer that will be updated asynchronously

queueSize - maximum size of the update queue, if the queue fills up older entries will be dropped

expireTime - age in milliseconds before an update expires and will not be passed on to the wrapped observer

AsyncMetricObserver

public AsyncMetricObserver(java.lang.String name,
                           MetricObserver observer)

Creates a new instance with an unbounded queue and no expiration time.

Parameters:

name - name of this observer

observer - a wrapped observer that will be updated asynchronously

AsyncMetricObserver

public AsyncMetricObserver(java.lang.String name,
                           MetricObserver observer,
                           int queueSize)

Creates a new instance with no expiration time.

Parameters:

name - name of this observer

observer - a wrapped observer that will be updated asynchronously

queueSize - maximum size of the update queue, if the queue fills up older entries will be dropped

Method Detail

updateImpl

public void updateImpl(java.util.List<Metric> metrics)

Update method that should be defined by sub-classes. This method will get invoked and counts will be maintained in the base observer.

Specified by:

updateImpl in class BaseMetricObserver

stop

public void stop()

Stop the background thread that pushes updates to the wrapped observer.