code: public void addMappingField(MappingField field) {
          if (field.isId())
              theId = field;
          else if (field.isName())
              theName = field;
        //wjw(2017-04-10),add,乐观锁
          else if (field.isVersion())
          	theVersion =field;
          
          byJava.put(field.getName(), field);
          byDB.put(field.getColumnName(), field);
          fields.add(field);
          columnComments.put(field.getName(), field.getColumnComment());
      }
docs: 增加映射字段
  
  @param field
  数据库实体字段