public Tile( int tilex, int tiley, FileChannel file, int fposition, SampleModel sm)
public Tile(int tilex, int tiley, FileChannel file, int fposition)
   public Tile(      int tilex,      int tiley,      FileChannel file,      int fposition,      SampleModel sm)   {      this.file = file;      this.fposition = fposition;      xloc = TILE_SIZE * tilex;      yloc = TILE_SIZE * tiley;      location = LOCATION_INVALID;      data = null;      lastused = System.currentTimeMillis();      this.sm = (SinglePixelPackedSampleModel) sm;      masks = this.sm.getBitMasks();      offsets = this.sm.getBitOffsets();      validate(); // go ahead and validate this tile   }