java - Is Void really uninstantiable?

Question

The javadoc for Void says:

The Void class is an uninstantiable placeholder class to hold a reference to the Class object representing the Java keyword void.

but the constructor is simply:

private Void() {}

and this code instantiates a Void:

Constructor<Void> c = Void.class.getDeclaredConstructor();
c.setAccessible(true);
Void v = c.newInstance(); // Hello sailor

So Void is not uninstantiable.

Would there have been a way to make Void truly uninstantiable?

Answer 1

Rohit is quite right that throwing an exception is "good enough" for most use cases. However, it looks like it might be possible to bypass even that, using sun.misc.Unsafe:

public native Object allocateInstance(Class cls) throws InstantiationException

Allocate an instance but do not run any constructor. Initializes the class if it has not yet been.

(Note that I haven't actually tested that this works)