code: public void setAttribute(String name, Object value) {
          if (attributes == null) {
              synchronized (this) {
                  if (attributes == null) {
                      attributes = new ConcurrentHashMap<String, Object>(4);
                  }
              }
          }
          this.attributes.put(name, value);
      }
docs: 设置挂在DAO方法上的属性
  
  @param name
  @param value