net.grinder.util

Class SleeperImplementation

java.lang.Object

net.grinder.util.SleeperImplementation

All Implemented Interfaces:

Sleeper, TimeAuthority

public final class SleeperImplementation
extends Object
implements Sleeper

Manage sleeping.

Several threads can safely use the same Sleeper.

Author:

Philip Aston

Nested Class Summary

Nested classes/interfaces inherited from interface net.grinder.util.Sleeper

Sleeper.ShutdownException

Constructor Summary

Constructors

Constructor and Description
SleeperImplementation(TimeAuthority timeAuthority, org.slf4j.Logger logger, double factor, double limit9975Factor) The constructor.

Method Summary

Methods

Modifier and Type	Method and Description
long	getTimeInMilliseconds() Return the current time in milliseconds.
void	shutdown() Shutdown this Sleeper.
static void	shutdownAllCurrentSleepers() Shutdown all Sleepers that are currently constructed.
void	sleepFlat(long maximumTime) Sleep for a time based on the maximumTime parameter.
void	sleepNormal(long meanTime) Sleep for a time based on the meanTime parameter.
void	sleepNormal(long meanTime, long sigma) Sleep for a random time drawn from a pseudo normal distribution.

Methods inherited from class java.lang.Object

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

Constructor Detail

SleeperImplementation

public SleeperImplementation(TimeAuthority timeAuthority,
                     org.slf4j.Logger logger,
                     double factor,
                     double limit9975Factor)

The constructor.

Parameters:

timeAuthority - An authority on the current time.

logger - A logger to chat to. Pass null for no chat.

factor - All sleep times are modified by this factor.

limit9975Factor - See sleepNormal(long).

Method Detail

shutdownAllCurrentSleepers

public static void shutdownAllCurrentSleepers()

Shutdown all Sleepers that are currently constructed.

shutdown

public void shutdown()

Shutdown this Sleeper. Once called, all sleep method invocations will throw Sleeper.ShutdownException, including those already sleeping.

Specified by:

shutdown in interface Sleeper

getTimeInMilliseconds

public long getTimeInMilliseconds()

Return the current time in milliseconds.

This is an abstraction over System.currentTimeMillis() and the J2SE 5 System.nanoTime() method.

Specified by:

getTimeInMilliseconds in interface TimeAuthority

Returns:

The time. The base time is the Epoch, even if the implementation uses System.nanoTime().

sleepNormal

public void sleepNormal(long meanTime)
                 throws Sleeper.ShutdownException

Sleep for a time based on the meanTime parameter. The actual time is taken from a pseudo normal distribution. Approximately 99.75% of times will be within (100* limit9975Factor) percent of the meanTime.

Specified by:

sleepNormal in interface Sleeper

Parameters:

meanTime - Mean time.

Throws:

Sleeper.ShutdownException - If this Sleeper has been shutdown.

sleepNormal

public void sleepNormal(long meanTime,
               long sigma)
                 throws Sleeper.ShutdownException

Sleep for a random time drawn from a pseudo normal distribution.

Specified by:

sleepNormal in interface Sleeper

Parameters:

meanTime - Mean time.

sigma - Standard deviation.

Throws:

Sleeper.ShutdownException - If this Sleeper has been shutdown.

sleepFlat

public void sleepFlat(long maximumTime)
               throws Sleeper.ShutdownException

Sleep for a time based on the maximumTime parameter. The actual time is taken from a pseudo random flat distribution between 0 and maximumTime.

Specified by:

sleepFlat in interface Sleeper

Parameters:

maximumTime - Maximum time.

Throws:

Sleeper.ShutdownException - If this Sleeper has been shutdown.