您可以尝试创建与您返回的类型相同的类型:

You could try creating the same type you are returning:

List<HashMap<String, String>> = new ArrayList<HashMap<String, String>>();

不需要声明实现类型，即ArrayList.List 接口更通用，因此在将变量声明为具体类型时，问问自己是否有必要这样做.看针对接口编程

There is no need to declare the implementation type, i.e. ArrayList. The List interface is more general, so when declaring variables as a concrete type, ask yourself if this is necessary. See Programming against interface