protected short[] fetchTileArray(TileMatrix tileMatrix, int row, int column) {
long key = tileKey(tileMatrix, row, column);
ImageSource tileSource = this.coverageSource.get(key);
if (tileSource == null) {
tileSource = this.tileFactory.createTileSource(tileMatrix, row, column);
this.coverageSource.put(key, tileSource, 1);
}
short[] tileArray = this.coverageCache.get(tileSource);
if (tileArray == null && this.isEnableRetrieval()) {
this.coverageRetriever.retrieve(tileSource, null, this);
}
return tileArray;
}