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IP属地:重庆
  • 评论里好几个讨论这个问题,刚好在StackOverflow上看到对这个问题的说明。

    JAVA泛型通配符T,E,K,V区别,T以及Class<T>,Class<?>的区别

    1. 先解释下泛型概念 泛型是Java SE 1.5的新特性,泛型的本质是参数化类型,也就是说所操作的数据类型被指定为一个参数。这种参数类型可以用在类、接口和方法的创建中,分...

  • Many assume that because class C inherits from class P, that List<C> also inherits from List<P>. But this is not the case. Although String is a subset of Object, but List<String> is not inherited from List<Object>.The reason why was that if we could cast from List<String> to List<Object>, then we could put Objects into that list, thus violating the original contract of List<String> when attempting to retrieve an element.

    JAVA泛型通配符T,E,K,V区别,T以及Class<T>,Class<?>的区别

    1. 先解释下泛型概念 泛型是Java SE 1.5的新特性,泛型的本质是参数化类型,也就是说所操作的数据类型被指定为一个参数。这种参数类型可以用在类、接口和方法的创建中,分...