code: public Object readObject(Object pId, Class pObjClass, Hashtable pMapping)
          throws SQLException {
          return readObject(pId, pObjClass, pMapping, null);
      }
docs: Reads the object with the given id from the database, using the given
  mapping.
  
  @param id An object uniquely identifying the object to read
  @param objClass The clas
  @return The Object read, or null in no object is found