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为什么不能定立一个 has图?
原标题:Why can t a hash map be static..?

为什么这一辛迪加不合法? 你们能否看一看设计问题是什么,不能让哈希姆普像这样的声明静态?

static HashMap<String,  String> map2 = new HashMap<String,  String> ();
最佳回答
static HashMap<String,  String> map2 = new HashMap<String,  String> (); 

如果你在班级而不是在某种方法上拥有这一法典,则完全有效。

如果有的话?

www.un.org/Depts/DGACM/index_spanish.htm 更新后:

你们在方法一级宣布变数,在方法一级不允许固定变量。

stat变量。 每组1人。 因此,在计算方法之后,只有一种方法内可见的变量,即:die,即为平级,是没有意义的。 至少是 Java如何看待这一问题。

问题回答

该宣言本身是完全合法的。 我可以想到,你有两点错误:

  • You put that declaration somewhere where static declarations are not allowed (e.g. inside a method).
  • You did not import java.util.HashMap (of course in that case the error has nothing to do with your use of the static keyword).

你宣布是完全正确的,也许你会从非正常情况/方法重新尝试使用。

我们可以宣布,在java的任何收集都是静态的。 因此,你的声明没有任何错误。

static HashMap<String,  String> map2 = new HashMap<String,  String> ();




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