com.github.rollingmetrics.counter

Class ResetOnSnapshotCounter

java.lang.Object

com.github.rollingmetrics.counter.ResetOnSnapshotCounter

All Implemented Interfaces:

WindowCounter

public class ResetOnSnapshotCounter
extends Object
implements WindowCounter

The counter which reset its state to zero after each invocation of getSum().

Concurrency properties:

• Writing is lock-free. Writers do not block writers and readers.
• Sum reading always happen inside synchronized block, so readers block each other, but readers never block writers.

Usage recommendations:

• When you do not need in "rolling time window" semantic. Else use SmoothlyDecayingRollingCounter
• When you need in 100 percents guarantee that one measure can not be reported twice.
• Only if one kind of reader interests in value of counter. Usage of this implementation for case of multiple readers will be a bad idea because of readers will steal data from each other.

See Also:

SmoothlyDecayingRollingCounter

Constructor Summary

Constructors

Constructor and Description
ResetOnSnapshotCounter()

Method Summary

Modifier and Type	Method and Description
void	add(long delta) Increment the counter by delta.
long	getSum() Returns the counter's current value.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

ResetOnSnapshotCounter

public ResetOnSnapshotCounter()

Method Detail

add

public void add(long delta)

Description copied from interface: WindowCounter

Increment the counter by delta. If You want to decrement instead of increment then use negative delta.

Specified by:

add in interface WindowCounter

Parameters:

delta - the amount by which the counter will be increased

getSum

public long getSum()

Description copied from interface: WindowCounter

Returns the counter's current value.

Specified by:

getSum in interface WindowCounter

Returns:

the counter's current value

toString

public String toString()

Overrides:

toString in class Object