== operator with Strings

The code below should not print "Bye", since == operator is used to compare references, but oddly enough, "Bye" is still printed. Why does this happen? I'm using Netbeans 6.9.1 as the IDE.

public class Test {
    public static void main(String [] args) {
        String test ="Hi";
        if(test=="Hi"){
            System.out.println("Bye");
        }
    }
}