private   long  getCheckSum(File file) {
        CheckedInputStream cis =  null ;
         try  {
            cis =  new  CheckedInputStream( new  FileInputStream(file),  new  CRC32());
             byte [] tempBuf =  new   byte [ 128 ];
             while  (cis.read(tempBuf) >=  0 ) {
                //Read files to checksum
            }
        }
         catch  (IOException e) {
            e.printStackTrace();
        }
         finally  {
             if  (cis !=  null ) {
                 try  {
                    cis.close();
                }
                 catch  (IOException e) {
                    e.printStackTrace();
                }
            }
        }

         long  checksum =  0 ;
         if  (cis !=  null ) {
            checksum = cis.getChecksum().getValue();
        }

         return  checksum;
    }