为什么构造函数不能是最终的 [英] Why constructors cannot be final

问题描述

为什么构造函数在Java中不是final，static或abstract？

Why can't constructors be final, static, or abstract in Java?

例如，你能向我解释为什么这是无效的吗？ >

For instance, can you explain to me why this is not valid?

public class K {

    abstract public K() {
        // ...
    }
}

推荐答案

一个方法 final 意味着：你不想让任何类覆盖它。但是构造函数（根据Java语言规范）不能被覆盖，所以它是干净的。

When you set a method as final it means: "You don't want any class override it." But the constructor (according to the Java Language Specification) can't be overridden, so it is clean.

当你设置一个方法 abstract 这意味着：方法没有一个body，它应该在子类中实现。但是当使用 new 关键字时，隐式调用构造函数，所以它不能缺少正文。

When you set a method as abstract it means: "The method doesn't have a body and it should be implemented in a child class." But the constructor is called implicitly when the new keyword is used so it can't lack a body.

你设置一个方法为 static 意味着：该方法属于类，而不是特定的对象。但是隐式调用构造函数来初始化一个对象，所以没有任何目的拥有一个静态构造函数。

When you set a method as static it means: "The method belongs to the class, not a particular object." But the constructor is implicitly called to initialize an object, so there is no purpose in having a static constructor.

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