When do you use varargs in Java?

java variadic-functions
Harry Quince picture Harry Quince · Apr 20, 2009 · Viewed 163.6k times · Source

I'm afraid of varargs. I don't know what to use them for.

Plus, it feels dangerous to let people pass as many arguments as they want.

What's an example of a context that would be a good place to use them?

Answer

Andy White picture Andy White · Apr 20, 2009

Varargs are useful for any method that needs to deal with an indeterminate number of objects. One good example is String.format. The format string can accept any number of parameters, so you need a mechanism to pass in any number of objects.

String.format("This is an integer: %d", myInt);
String.format("This is an integer: %d and a string: %s", myInt, myString);

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