/*
* Created on 9 Aug 2006
* Created by Paul Gardner
* Copyright (C) 2006 Aelitis, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* AELITIS, SAS au capital de 46,603.30 euros
* 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
*
*/
package org.gudy.azureus2.core3.util;
public class
FrequencyLimitedDispatcher
{
private AERunnable target;
private long min_millis;
private long last_run;
private DelayedEvent delay_event;
public
FrequencyLimitedDispatcher(
AERunnable _target,
int _min_frequency_millis )
{
target = _target;
min_millis = _min_frequency_millis;
}
public void
setSingleThreaded()
{
final AERunnable old_target = target;
target =
new AERunnable()
{
private boolean running;
private boolean pending;
public void
runSupport()
{
synchronized( this ){
if ( running ){
pending = true;
return;
}
running = true;
}
try{
old_target.runSupport();
}finally{
boolean was_pending;
synchronized( this ){
running = false;
was_pending = pending;
pending = false;
}
if ( was_pending ){
dispatch();
}
}
}
};
}
public void
dispatch()
{
long now = SystemTime.getMonotonousTime();
boolean run_it = false;
synchronized( this ){
if ( delay_event == null ){
long delay = min_millis - (now - last_run );
if ( now < last_run || delay <= 0 ){
last_run = now;
run_it = true;
}else{
// run too recently
delay_event =
new DelayedEvent(
"FreqLimDisp",
delay,
new AERunnable()
{
public void
runSupport()
{
long now = SystemTime.getMonotonousTime();
synchronized( FrequencyLimitedDispatcher.this ){
last_run = now;
delay_event = null;
}
target.run();
}
});
}
}
}
if ( run_it ){
target.run();
}
}
}