package org.apidesign.stateful.api;

 import java.lang.annotation.Documented;

 /**

  *

  * @author Jaroslav Tulach <jtulach@netbeans.org>

  */

 // BEGIN: progress.annotations

 public abstract class ProgressStateMachine {

     /** Annotation that helps users and IDEs to understand what

      * is the allowed order of method calls on instances of given class.

      */

     @Documented

     public @interface StateChange {

         /** What is the required state of the object before given method

          * is called.

          * @return "*" means any state, otherwise specify the state's name

          */

         String from() default "*";

         /** The state object enters after the method successfully returns.

          * @return name of new state

          */

         String to();

     }

     @StateChange(to="ready")

     public static ProgressStateMachine create(String name) {

         return createImpl(name);

     }

     @StateChange(from="ready", to="started")

     public abstract void start(int totalAmount);

     @StateChange(from="started", to="started")

     public abstract void progress(int howMuch);

     @StateChange(to="finished")

     public abstract void finish();

     // FINISH: progress.annotations

     private static ProgressStateMachine createImpl(String name) {

         return null; // implementation left out, similar to Progress.java

     }

 }