Java表达_第2页-阿里云

Java 泛型为什么不能写 <? is extended by V>? 如何表达相同的意思？

比如我有 class A，class B extends A；class template，class template。要在 template 里存一个名叫 template_parent 的实例变量指向一个 template，而 template 的 template_parent 为 nul...

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更新时间 2023-10-31 06:58:29

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