In Java, is there any difference between this two function declarations?
public void foo() {/*...*/}
public void foo(void) {/*...*/}
Here you
The latter declaration illegal in Java. You can't declare a method like that. You should get an error like this:
Test.java:8: error: <identifier> expected
public void foo(void) {/*...*/}
^
1 error
So not only is there no point - you simply won't find valid code which attempts to use this style.
You can try
public void foo(Void v) {/*...*/}