Java "params" in method signature?

java variadic-functions params method-declaration
Omar Kooheji picture Omar Kooheji · Feb 6, 2009 · Viewed 77.3k times · Source

In C#, if you want a method to have an indeterminate number of parameters, you can make the final parameter in the method signature a params so that the method parameter looks like an array but allows everyone using the method to pass as many parameters of that type as the caller wants.

I'm fairly sure Java supports similar behaviour, but I cant find out how to do it.

Answer

David Grant picture David Grant · Feb 6, 2009

In Java it's called varargs, and the syntax looks like a regular parameter, but with an ellipsis ("...") after the type:

public void foo(Object... bar) {
    for (Object baz : bar) {
        System.out.println(baz.toString());
    }
}

The vararg parameter must always be the last parameter in the method signature, and is accessed as if you received an array of that type (e.g. Object[] in this case).

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