question: public CacheObject load ( Object key , int x , int y , int zoomLevel , Projection proj ) { if ( key instanceof String ) { String imagePath = ( String ) key ; if ( verbose ) { logger . fine ( "fetching file for cache: " + imagePath ) ; } try { URL imageURL = PropUtils . getResourceOrFileOrURL ( imagePath ) ; if ( imageURL != null ) { BufferedImage bi = BufferedImageHelper . getBufferedImage ( imageURL ) ; OMGraphic raster = createOMGraphicFromBufferedImage ( bi , x , y , zoomLevel , proj ) ; if ( raster != null ) { return new CacheObject ( imagePath , raster ) ; } } else { logger . fine ( "Can't find resource located at " + imagePath ) ; } } catch ( MalformedURLException e ) { logger . fine ( "Can't find resource located at " + imagePath ) ; } catch ( InterruptedException e ) { logger . fine ( "Reading the image file was interrupted: " + imagePath ) ; } catch ( Exception fnfe ) { logger . fine ( "file not found: " + imagePath ) ; } } return null ; }
target:  Called to load cache object from data source, when not found in cache.