blocks|key|1390225|text|标记为final的类上的私有构造函数和静态方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1390226|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Private constructor and static methods on a class marked as final.

blocks|key|1390285|text|将类声明为static是没有意义的。只需将其方法声明为static，并像往常一样从类名调用它们，就像Java的Math类一样。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1390286|此外，尽管没有严格的必要将构造函数设置为私有，但这样做也是一个好主意。将构造函数标记为私有可以防止其他人创建您的类的实例，然后从这些实例中调用静态方法。(这些调用在Java中的工作方式完全相同，它们只是误导并损害了代码的可读性。)|1390287|entityMap|0|LINK|mutability|MUTABLE|url|http://java.sun.com/javase/6/docs/api/java/lang/Math.html^0|5|6|R|6|1J|4|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@$9|Q|A|R|B|C]|$9|S|A|T|B|C]]|D|@$9|U|A|V|1|W]]|E|$]]|$1|F|3|G|5|6|7|X|8|@]|D|@]|E|$]]|$1|H|3|-4|5|6|7|Y|8|@]|D|@]|E|$]]]|I|$J|$5|K|L|M|E|$N|O]]]]

There's no point in declaring the class as <code>static</code>. Just declare its methods <code>static</code> and call them from the class name as normal, like Java's <a href="http://java.sun.com/javase/6/docs/api/java/lang/Math.html" rel="nofollow noreferrer">Math</a> class.

Also, even though it isn't strictly necessary to make the constructor private, it is a good idea to do so. Marking the constructor private prevents other people from creating instances of your class, then calling static methods from those instances. (These calls work exactly the same in Java, they're just misleading and hurt the readability of your code.)

blocks|key|1390315|text|只是游到上游，静态成员和类不参与OO，因此是邪恶的。不，不是邪恶的，但说真的，我会推荐一个具有单例模式的常规类来访问。通过这种方式，如果您需要在任何情况下覆盖行为，它不是一个主要的重新装备。OO是你的朋友:-)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1390316|我的$.02|1390317|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

Just to swim upstream, static members and classes do not participate in OO and are therefore evil. No, not evil, but seriously, I would recommend a regular class with a singleton pattern for access. This way if you need to override behavior in any cases down the road, it isn't a major retooling. OO is your friend :-)

My $.02

blocks|key|1174907|text|评论“私有构造函数”的论点:来吧，开发人员并没有那么愚蠢；但是他们很懒。创建一个对象然后调用静态方法？不会发生的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1174908|不要花费太多的时间来确保你的类不会被滥用。对你的同事要有信心。无论你如何保护你的类，总有一种方法可以滥用它。唯一不能被滥用的是一个完全无用的东西。|1174909|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

comment on the "private constructor" arguments: come on, developers are not that stupid; but they ARE lazy. creating an object then call static methods? not gonna happen.

don't spend too much time to make sure your class cannot be misused. have some faith for your colleagues. and there is always a way to misuse your class no matter how you protect it. the only thing that cannot be misused is a thing that is completely useless.

blocks|key|1390450|text|听起来您有一个类似于java.lang.Math的实用程序类。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1390451|这里的方法是带有私有构造函数和静态方法的最终类。|1390452|但要注意这对可测试性有什么影响，我建议您阅读本文|1390453|Static+Methods+are+Death+to+Testability|1390454|entityMap|0|LINK|mutability|MUTABLE|url|http://java.sun.com/javase/6/docs/api/java/lang/Math.html|1|http://java.dzone.com/articles/static-methods-are-death-testa^0|A|E|0|0|0|0|0|13|1|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@$A|U|B|V|1|W]]|C|$]]|$1|D|3|E|5|6|7|X|8|@]|9|@]|C|$]]|$1|F|3|G|5|6|7|Y|8|@]|9|@]|C|$]]|$1|H|3|I|5|6|7|Z|8|@]|9|@$A|10|B|11|1|12]]|C|$]]|$1|J|3|-4|5|6|7|13|8|@]|9|@]|C|$]]]|K|$L|$5|M|N|O|C|$P|Q]]|R|$5|M|N|O|C|$P|S]]]]

Sounds like you have a utility class similar to <a href="http://java.sun.com/javase/6/docs/api/java/lang/Math.html" rel="noreferrer">java.lang.Math</a>. 
The approach there is final class with private constructor and static methods.

But beware of what this does for testability, I recommend reading this article 
<a href="http://java.dzone.com/articles/static-methods-are-death-testa" rel="noreferrer">Static Methods are Death to Testability</a>

blocks|key|1175053|text|您可以使用lombok+https://projectlombok.org/features/experimental/UtilityClass中的@UtilityClass注释|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1175054|entityMap|0|LINK|mutability|MUTABLE|url|https://projectlombok.org/features/experimental/UtilityClass^0|C|1O|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

You can use @UtilityClass annotation from lombok <a href="https://projectlombok.org/features/experimental/UtilityClass" rel="nofollow noreferrer">https://projectlombok.org/features/experimental/UtilityClass</a>

I have a class full of utility functions. Instantiating an instance of it makes no semantic sense, but I still want to call its methods. What is the best way to deal with this? Static class? Abstract?

Java: Static Class?

Java

我有一个满是实用函数的类。实例化它的一个实例没有任何语义意义，但我仍然想调用它的方法。处理这个问题的最好方法是什么？静态类？摘要？

问Java:静态类？
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