@Override
public boolean shouldRemove(
Entry<TileIndex, TileCacheEntry<T>> entry,
Map<TileIndex, TileCacheEntry<T>> map,
int suggestedMaxSize) {
if (null == entry) {
return false;
} else if (null == entry.getValue()) {
return true;
} else {
TileCacheEntry<T> value = entry.getValue();
if (value.hasBeenRetrieved() || value.age() > _maxTileAge) {
// This entry has been received, or is to old for us to
// care; just remove it.
return true;
} else {
// First see if there is anything which has already been
// handled, so can be freely deleted.
for (Pair<TileIndex, Long> hasData : _haveData) {
TileIndex index = hasData.getFirst();
TileCacheEntry<T> entryWithData = _cache.get(index);
if (entryWithData.hasBeenRetrieved()) {
_cache.remove(index);
return false;
}
}
// If we get this far, there was nothing already handled.
//
// See if there's anything so old we just don't care about
// its safety any more.
if (_orderedKeys.size() > 0) {
TileIndex oldestKey = _orderedKeys.get(0);
TileCacheEntry<T> oldestEntry = _cache.get(oldestKey);
if (oldestEntry.age() > _maxTileAge) {
_cache.remove(oldestKey);
}
}
return false;
}
}
}
@Override
public int compare(Pair<TileIndex, Long> o1, Pair<TileIndex, Long> o2) {
return -o1.getSecond().compareTo(o2.getSecond());
}