// concurrent/Machina.java
// (c)2017 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.
import onjava.Nap;

public class Machina {
 public enum State {
 START, ONE, TWO, THREE, END;
 State step() {
 if(equals(END)) return END;
 return values()[ordinal() + 1];
 }
 }
 private State state = State.START;
 private final int id;
 public Machina(int id) { this.id = id; }
 public static Machina work(Machina m) {
 if(!m.state.equals(State.END)){
 new Nap(0.1);
 m.state = m.state.step();
 }
 System.out.println(m);
 return m;
 }
 @Override
 public String toString() {
 return "Machina" + id + ": " +
 (state.equals(State.END)? "complete" : state);
 }
}