org.dice_research.squirrel.fetcher.delay

Class StaticDelayer

java.lang.Object

org.dice_research.squirrel.fetcher.delay.StaticDelayer

All Implemented Interfaces:

Delayer

public class StaticDelayer
extends Object
implements Delayer

A simple implementation of the Delayer interface using a static delay between requests.

Note that this implementation is not thread-safe!

Author:

Michael Röder (michael.roeder@uni-paderborn.de)

Field Summary

Fields

Modifier and Type	Field and Description
private long	delay The delay (in ms) that should be introduced between two requests.
private long	lastRequestTimeStamp The time stamp (in ms) at which the last request has been finished.

Constructor Summary

Constructors

Constructor and Description
StaticDelayer(long delay) Constructor.
StaticDelayer(long delay, long lastRequestTimeStamp) Constructor.

Method Summary

Modifier and Type	Method and Description
long	getDelay() Returns the delay (in ms) that this instance typically would introduce between two consecutive requests.
void	getRequestPermission() Waits for the permission to perform a new request.
void	requestFinished() informs the Delayer instance about the finished request.

Methods inherited from class java.lang.Object

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

Field Detail

delay

private long delay

The delay (in ms) that should be introduced between two requests.

lastRequestTimeStamp

private long lastRequestTimeStamp

The time stamp (in ms) at which the last request has been finished.

Constructor Detail

StaticDelayer

public StaticDelayer(long delay)

Constructor.

Parameters:

delay - the delay (in ms) that should be introduced between two requests

StaticDelayer

public StaticDelayer(long delay,
                     long lastRequestTimeStamp)

Constructor.

Parameters:

delay - the delay (in ms) that should be introduced between two requests

lastRequestTimeStamp - the time stamp (in ms) at which the last request has been finished

Method Detail

getRequestPermission

public void getRequestPermission()
                          throws InterruptedException

Description copied from interface: Delayer

Waits for the permission to perform a new request.

Specified by:

getRequestPermission in interface Delayer

Throws:

InterruptedException - if the internal waiting is interrupted.

requestFinished

public void requestFinished()

Description copied from interface: Delayer

informs the Delayer instance about the finished request. Note that missing to call this method might lead to a deadlock.

Specified by:

requestFinished in interface Delayer

getDelay

public long getDelay()

Description copied from interface: Delayer

Returns the delay (in ms) that this instance typically would introduce between two consecutive requests.

Specified by:

getDelay in interface Delayer

Returns:

the delay (in ms) that this instance typically would introduce between two consecutive requests