The way to use the ellipsis or varargs inside the method is as if it were an array:
public void PrintWithEllipsis(String...setOfStrings) {
for (String s : setOfStrings)
System.out.println(s);
}
This method can be called as following:
obj.PrintWithEllipsis(); // prints nothing
obj.PrintWithEllipsis("first"); // prints "first"
obj.PrintWithEllipsis("first", "second"); // prints "first\nsecond"
Inside PrintWithEllipsis, the type of setOfStrings is an array of String.
So you could save the compiler some work and pass an array:
String[] argsVar = {"first", "second"};
obj.PrintWithEllipsis(argsVar);
For varargs methods, a sequence parameter is treated as being an array of the same type. So if two signatures differ only in that one declares a sequence and the other an array, as in this example:
void process(String[] s){}
void process(String...s){}
then a compile-time error occurs.
Source: The Java Programming Language specification, where the technical term is variable arity parameter rather than the common term varargs.