Demo for GraphPlanAlgorithm added.

Author: RuedigerLunde

aima-core/src/main/java/aima/core/logic/planning/ActionSchema.java

@@ -21,6 +21,12 @@
  * @author samagra
  */
 public class ActionSchema {
+
+    /**
+     * Name for persistence actions.
+     */
+    public final static String NO_OP = "No-op";
+
     List<Term> variables;// list of variables
     List<Literal> precondition; //PRECONDITION: treated as a conjunction of fluents
     List<Literal> effects;//EFFECT: treated as a conjunction of fluents
@@ -56,11 +62,17 @@ private void sortEffects() {
     @Override
     public String toString() {
         String result = "Action(" + this.getName() + ")\n\tPRECOND:";
-        for (Literal precond : getPrecondition())
-            result = result + "^" + precond.toString();
+        String and = "";
+        for (Literal precond : getPrecondition()) {
+            result = result + and + precond.toString();
+            and = "^";
+        }
         result = result + "\n\tEFFECT:";
-        for (Literal effect : getEffects())
-            result = result + "^" + effect.toString();
+        and = "";
+        for (Literal effect : getEffects()) {
+            result = result + and + effect.toString();
+            and = "^";
+        }
         return result;
     }
 

aima-core/src/main/java/aima/core/logic/planning/GraphPlanAlgorithm.java

@@ -3,6 +3,7 @@
 import aima.core.logic.fol.kb.data.Literal;
 
 import java.util.*;
+import java.util.stream.Collectors;
 
 /**
  * Artificial Intelligence A Modern Approach (3rd Edition): Figure 10.9 page
@@ -139,6 +140,13 @@ private List<List<ActionSchema>> extractSolution(Graph graph, List<Literal> goal
         return null;
     }
 
+    public List<ActionSchema> asFlatList(List<List<ActionSchema>> solution) {
+        List<ActionSchema> result = solution.stream().flatMap(Collection::stream)
+                .filter(actionSchema -> !ActionSchema.NO_OP.equals(actionSchema.getName()))
+                .collect(Collectors.toList());
+        return result;
+    }
+
     /**
      * This method is used to check if all goals are present in a particular state
      * and none of them has a mutex link.
@@ -155,8 +163,7 @@ private boolean checkAllGoalsNonMutex(Level level, List<Literal> goals) {
         for (Object literal : goals) {
             List<Object> mutexOfGoal = level.getMutexLinks().get(literal);
             if (mutexOfGoal != null) {
-                for (Object object :
-                        mutexOfGoal) {
+                for (Object object : mutexOfGoal) {
                     if (goals.contains((Literal) object)) {
                         mutexCheck = true;
                         break;

aima-core/src/main/java/aima/core/logic/planning/Level.java

@@ -55,7 +55,7 @@ public Level(Level prevLevel, Problem problem) {
             calculateNextLinks();
             calculateMutexLinks(null);
         }
-        addPersistentActions();
+        addPersistenceActions();
     }
 
     public Level(Level prevLevel, Problem problem, String extraLiterals) {
@@ -70,7 +70,7 @@ public void addExtraLiterals(String s) {
         }
         calculateNextLinks();
         calculateMutexLinks(getPrevLevel());
-        addPersistentActions();
+        addPersistenceActions();
     }
 
     public List<Object> getLevelObjects() {
@@ -93,10 +93,10 @@ public Problem getProblem() {
         return problem;
     }
 
-    private void addPersistentActions() {
+    private void addPersistenceActions() {
        if(getLevelObjects().get(0) instanceof Literal) {
            for (Object literal : getLevelObjects()) {
-               ActionSchema action = new ActionSchema("No-op", null,
+               ActionSchema action = new ActionSchema(ActionSchema.NO_OP, null,
                        Collections.singletonList((Literal) literal),
                        Collections.singletonList((Literal) literal));
                addToHashMap(literal, action, nextLinks);

aima-gui/src/main/java/aima/gui/demo/logic/GraphPlanAlgorithmDemo.java

@@ -0,0 +1,41 @@
+package aima.gui.demo.logic;
+
+import aima.core.logic.planning.ActionSchema;
+import aima.core.logic.planning.GraphPlanAlgorithm;
+import aima.core.logic.planning.PlanningProblemFactory;
+import aima.core.logic.planning.Problem;
+
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Demonstrates how the GraphPlanAlgorithm solves different example problems.
+ * @author Ruediger Lunde
+ */
+public class GraphPlanAlgorithmDemo {
+    public static void main(String[] args) {
+        GraphPlanAlgorithm algorithm = new GraphPlanAlgorithm();
+        List<Problem> problems = Arrays.asList(
+                PlanningProblemFactory.spareTireProblem(),
+                PlanningProblemFactory.goHomeToSFOProblem(),
+                PlanningProblemFactory.airCargoTransportProblem());
+
+        int i = 1;
+        for (Problem problem : problems) {
+            System.out.println("\n\nProblem " + i++);
+            System.out.println("Initial State:");
+            System.out.println(problem.getInitialState().getFluents());
+            System.out.println("Goal State:");
+            System.out.println(problem.getGoalState().getFluents());
+
+            long start = System.currentTimeMillis();
+            List<List<ActionSchema>> solution = algorithm.graphPlan(problem);
+            long duration = System.currentTimeMillis() - start;
+            System.out.println("Time for Planning [ms]: " + duration);
+
+            System.out.println("Plan:");
+            List<ActionSchema> sol = algorithm.asFlatList(solution);
+            sol.forEach(System.out::println);
+        }
+    }
+}

aima-gui/src/main/java/aima/gui/fx/applications/IntegratedAimaFxApp.java

@@ -5,12 +5,7 @@
 import aima.gui.demo.agent.TrivialVacuumDemo;
 import aima.gui.demo.agent.WumpusAgentDemo;
 import aima.gui.demo.learning.LearningDemo;
-import aima.gui.demo.logic.DpllDemo;
-import aima.gui.demo.logic.FolDemo;
-import aima.gui.demo.logic.PlFcEntailsDemo;
-import aima.gui.demo.logic.PlResolutionDemo;
-import aima.gui.demo.logic.TTEntailsDemo;
-import aima.gui.demo.logic.WalkSatDemo;
+import aima.gui.demo.logic.*;
 import aima.gui.demo.search.EightPuzzleDemo;
 import aima.gui.demo.search.MapColoringCspDemo;
 import aima.gui.demo.search.NQueensDemo;
@@ -95,6 +90,7 @@ public static void defineContent(IntegratedAppBuilder builder) {
 		builder.registerDemo(DpllDemo.class);
 		builder.registerDemo(WalkSatDemo.class);
 		builder.registerDemo(FolDemo.class);
+		builder.registerDemo(GraphPlanAlgorithmDemo.class);
 
 		// builder.registerDemo(ProbabilityDemo.class); // to slow.
 		builder.registerDemo(LearningDemo.class); // to slow.