code: @Override
  	public void close() throws IOException {
  		if (upload != null) {
  			flush();
  			// close the connection
  			try {
  				upload.close();
  			} catch (SQLException e) {
  				LOG.info("JDBC statement could not be closed: " + e.getMessage());
  			} finally {
  				upload = null;
  			}
  		}
  
  		if (dbConn != null) {
  			try {
  				dbConn.close();
  			} catch (SQLException se) {
  				LOG.info("JDBC connection could not be closed: " + se.getMessage());
  			} finally {
  				dbConn = null;
  			}
  		}
  	}
docs: Executes prepared statement and closes all resources of this instance.
  
  @throws IOException Thrown, if the input could not be closed properly.