java - Java 中的 void f(Class c) 和 void f(Class c) 有区别吗？

Question

无法编译以下 Java 代码并出现错误:名称冲突。

class Test {

    public void f(Class<?> c) {
    }

    public void f(Class c) {
    }
}

void f(Class c)之间有什么区别吗？无效 f(Class<?> c)在 Java 中？

Answer 1

在同一个类中声明，它们是覆盖等价的，会导致编译错误。

来自Java Language Specification

It is a compile-time error to declare two methods with override-equivalent signatures in a class.

在哪里

Two method signatures m1 and m2 are override-equivalent iff either m1 is a subsignature of m2 or m2 is a subsignature of m1.

和

The signature of a method m1 is a subsignature of the signature of a method m2 if either:

• m2 has the same signature as m1, or
• the signature of m1 is the same as the erasure (§4.6) of the signature of m2.

粗体是这里的问题。

删除Class<?>是Class .

Is there any difference between void f(Class c) and void f(Class c) in Java?

从调用者的角度来看，不。在方法体内，是的。在第一种情况下，参数具有 raw type Class .在第二种情况下，参数具有参数化类型 Class<?> .