// patterns/CleanTheFloor.java

// (c)2021 MindView LLC: see Copyright.txt

// We make no guarantees that this code is fit for any purpose.

// Visit http://OnJava8.com for more book information.

// State with different compositional interface.

class FloorCleaner {

private Attachment attachment = new Vacuum();

public void change(Attachment newAttachment) {

attachment = newAttachment;

}

public void clean() { attachment.action(); }

}

interface Attachment {

void action();

}

class Vacuum implements Attachment {

@Override public void action() {

System.out.println("Vacuuming");

}

}

class Mop implements Attachment {

@Override public void action() {

System.out.println("Mopping");

}

}

public class CleanTheFloor {

public static void main(String[] args) {

FloorCleaner floorCleaner = new FloorCleaner();

floorCleaner.clean();

floorCleaner.change(new Mop());

floorCleaner.clean();

}

}

/* Output:

Vacuuming

Mopping

*/