code: void addParent(final String name, final Object value)
              throws IllegalStateException {
  
          checkNotCompleted();
          _buffer.append(" <");
          _buffer.append(name);
          _buffer.append("=");
          addObjectIdentity(value);
          _buffer.append(">");
  
      }
docs: Adds a string representation of the given parent object. Does not call
  <code>toString</code> on the object to avoid infinite recursion.
  
  @param name
  the name of the field
  @param value
  the value of the field
  @throws IllegalStateException
  if the string representation has already been completed