code: void mapOutField(Object from, String from_out, Object to, String to_field) {
          if (from == ca.getComponent()) {
              throw new ComponentException("wrong connect:" + to_field);
          }
          ComponentAccess ca_from = lookup(from);
          Access from_access = ca_from.output(from_out);
          checkFA(from_access, from, from_out);
  
          try {
              FieldContent.FA f = new FieldContent.FA(to, to_field);
              ca_from.setOutput(from_out, new FieldObjectAccess(from_access, f, ens));
  
              if (log.isLoggable(Level.CONFIG)) {
                  log.config(String.format("@Out(%s) -> field(%s)", from_access, f.toString()));
              }
          } catch (Exception E) {
              throw new ComponentException("No such field '" + to.getClass().getCanonicalName() + "." + to_field + "'");
          }
      }
docs: Map a object to an output field.
  
  @param from
  @param from_out
  @param to
  @param to_field