Which overload will get selected for null in Java?

Question

If I write this line in Java:

JOptionPane.showInputDialog(null, \"Write something\");

Which method will be called?

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Answer 1

Neither. You'll get a compiler error asking you to clarify what method you want to call. You can do so by explicitly casting the first argument:

showInputDialog((Object) null, "Write something");

or

showInputDialog((Component) null, "Write something");

Update I should have known - never doubt Jon Skeet. The problem I've referred to above only occurs when it's impossible to determine which method is more specific. Here's a test case:

public class Test {

  public void doSomething(String arg1, Object arg2) {
    System.out.println("String, Object");
  }

  public void doSomething(Object arg1, String arg2) {
    System.out.println("Object, String");
  }

  public static void main(String[] args) {
    Test test = new Test();
    test.doSomething(null, null);
  }
}

The above will give a compiler error.