if ( !interests.isEmpty() )
{
double oldPower = lastStoredPower;
lastStoredPower = getStoredPower();
EnergyThreshold low = new EnergyThreshold( Math.min( oldPower, lastStoredPower ), null );
EnergyThreshold high = new EnergyThreshold( Math.max( oldPower, lastStoredPower ), null );
for (EnergyThreshold th : interests.subSet( low, true, high, true ))
{
((EnergyWatcher) th.watcher).post( this );
}
}