question: public Bitmap loadBitmap ( String uri , int reqWidth , int reqHeight ) { Bitmap bitmap = loadBitmapFromMemCache ( uri ) ; if ( bitmap != null ) { Log . d ( TAG , "loadBitmapFromMemCache,url:" + uri ) ; return bitmap ; } try { bitmap = loadBitmapFromDiskCache ( uri , reqWidth , reqHeight ) ; if ( bitmap != null ) { Log . d ( TAG , "loadBitmapFromDisk,url:" + uri ) ; return bitmap ; } bitmap = loadBitmapFromHttp ( uri , reqWidth , reqHeight ) ; Log . d ( TAG , "loadBitmapFromHttp,url:" + uri ) ; } catch ( IOException e ) { e . printStackTrace ( ) ; } if ( bitmap == null && ! mIsDiskLruCacheCreated ) { Log . w ( TAG , "encounter error, DiskLruCache is not created." ) ; bitmap = downloadBitmapFromUrl ( uri ) ; } return bitmap ; }
target:  load bitmap from memory cache or disk cache or network.