memo

1. Class with Static functions:
   If with high calling frequency, we need to refactor to non-static function, parse with different object of the Class.
2. Path Separator VS separator
   File.pathSeparator: separate file path in PATH environment vairable, ";"
   File.separator: "/" or "\" to split up the path of a file
3. Close the resource with the block
   Example: SQL Clean way to close ResultSet
   Use CachedRowSet

 
 public static ResultSet executeQuery(String sql, String[] parameters){
  DataSource ds = DBConnector.setupDataSource();
  try (
   Connection conn = ds.getConnection();
   PreparedStatement ps = createPreparedStatement(conn,sql,parameters);
   ResultSet rs = ps.executeQuery();
  ) {
   CachedRowSet rowset = new CachedRowSetImpl();
   rowset.populate(rs);
   return rowset;
  } catch (SQLException e) {
   Logger lgr = Logger.getLogger(SqlHelper.class);
   lgr.log(Level.WARNING,e.getMessage(),e);
  }
  return null;
 }

sdf