code: public List<String> getFieldValues(String fieldName) {
          Utils.require(!Utils.isEmpty(fieldName), "fieldName");
          
          return m_valueMap.get(fieldName);
      }
docs: Get all values of the field with the given name or null if no values are assigned
  to the given field. If the field has at least one value, the list returned is *not*
  copied. This means it may have duplicate values as well.
  
  @param  fieldName    Name of a field.
  @return              Set of all values assigned to the field.