I am giving the code and I am not getting true even I use the correct regular expression. Please correct me and explain me clearly as I might not looking at the actual problem in overlook.

I should be getting true and I am getting false. I tried cleaning the project but there is no use
I should be getting true and I am getting false. I tried cleaning the project but there is no use
code:

public class Sstring {
public static void main (String args[]) {

String str="K";

System.out.println(str.matches("\W"));

}

}
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