Code:

        ChangeDetector changeDetector = new ChangeDetector("unplugged","plugged");
        System.out.println(changeDetector.detectChange("unplugged"));
        System.out.println(changeDetector.detectChange("plugged"));
        System.out.println(changeDetector.detectChange("unplugged"));
        System.out.println(changeDetector.detectChange("hi"));
        System.out.println(changeDetector.detectChange("unplugged"));
        System.out.println(changeDetector.detectChange("plugged"));


I've been coding this little boiler plate code too many times, so it was time to make an auxiliary class.