8puzzle-example.java

enum Action { UP, DOWN, LEFT, RIGHT }

Hipster.SearchProblem p =
  ProblemBuilder.create()
	  .initialState(Arrays.asList(5,4,0,7,2,6,8,1,3))
	  .defineProblemWithExplicitActions()
	  .useActionFunction(new ActionFunction<Action, List<Integer>>() {
	      public Iterable<Action> actionsFor(List<Integer> board) {
		  return validMovements(board);
	      }
	  }).useTransitionFunction(new ActionStateTransitionFunction<Action, List<Integer>>() {
	      public List<Integer> apply(Action action, List<Integer> board) {
		  return applyActionToBoard(action, board);
	      }
	  }).useCostFunction(new CostFunction<Action, List<Integer>, Double>() {
	      public Double evaluate(Transition<Action, List<Integer>> transition) {
		  return 1d;
	      }
	  }).build();

System.out.println(Hipster.createAStar(p).search(Arrays.asList(0,1,2,3,4,5,6,7,8)));