泛型边界与pre-generics原始类型 [英] Generic bounds with pre-generics raw types

问题描述

我有一个元素类型为< K extends Comparable< K>> 的集合，因为它是有序的。

I've got a Collection with the element type of <K extends Comparable<K>> because it's ordered.

我试图在这个集合中使用Joda LocalTime - 例如 MyCollection< LocalTime> 。不幸的是，显然Joda是预典; LocalTime 实现原始可比较。

I'm trying to use Joda LocalTime with this collection - e.g. MyCollection<LocalTime>. Unfortunately, apparently Joda is pre-generics; LocalTime implements raw Comparable.

编译器错误

Bound mismatch: The type LocalTime is not a valid substitute 
for the bounded parameter <K extends Comparable<K>> of the type Interval<K>

我希望这只是一个警告，因为它很可能分配一个原始类型一个类型化的变量。

I would expect this to work with just a warning, as it's quite possible to assign a raw type to a typed variable.

为什么这不工作，我能做些什么呢？

Why doesn't this work, and what can I do about it?

最小代码示例：

class Holder<K extends Comparable<K>> { }
class WTF extends Holder<LocalTime> { }

推荐答案

c $ c> LocalTime 其中实现可比较的< K> 并通过所有方法调用。

You could create a wrapper class around LocalTime which implements Comparable<K> and passes through all the method calls.

这篇关于泛型边界与pre-generics原始类型的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！