SearchForStates now supported by most search algorithms.

Author: RuedigerLunde

aima-core/src/main/java/aima/core/search/framework/PrioritySearch.java

@@ -1,46 +1,55 @@
-package aima.core.search.framework;
-
-import java.util.Comparator;
-import java.util.List;
-
-import aima.core.agent.Action;
-import aima.core.search.framework.problem.Problem;
-import aima.core.search.framework.qsearch.QueueSearch;
-
-/**
- * Maintains a {@link QueueSearch} implementation and a node comparator. Search
- * is performed by creating a priority queue based on the given comparator and
- * feeding it to the QueueSearch implementation which finally controls the
- * simulated search space exploration.
- * 
- * @author Ravi Mohan
- * @author Ruediger Lunde
- */
-public class PrioritySearch implements SearchForActions {
-	private final QueueSearch implementation;
-	private final Comparator<Node> comparator;
-
-	public PrioritySearch(QueueSearch impl, Comparator<Node> comp) {
-		implementation = impl;
-		comparator = comp;
-	}
-
-	@Override
-	public List<Action> search(Problem p) {
-		return implementation.search(p, QueueFactory.<Node>createPriorityQueue(comparator));
-	}
-
-	public Comparator<Node> getComparator() {
-		return comparator;
-	}
-
-	@Override
-	public NodeExpander getNodeExpander() {
-		return implementation.getNodeExpander();
-	}
-	
-	@Override
-	public Metrics getMetrics() {
-		return implementation.getMetrics();
-	}
+package aima.core.search.framework;
+
+import java.util.Comparator;
+import java.util.List;
+
+import aima.core.agent.Action;
+import aima.core.search.framework.problem.Problem;
+import aima.core.search.framework.qsearch.QueueSearch;
+
+/**
+ * Maintains a {@link QueueSearch} implementation and a node comparator. Search
+ * is performed by creating a priority queue based on the given comparator and
+ * feeding it to the QueueSearch implementation which finally controls the
+ * simulated search space exploration.
+ * 
+ * @author Ravi Mohan
+ * @author Ruediger Lunde
+ */
+public class PrioritySearch implements SearchForActions, SearchForStates {
+	private final QueueSearch implementation;
+	private final Comparator<Node> comparator;
+
+	public PrioritySearch(QueueSearch impl, Comparator<Node> comp) {
+		implementation = impl;
+		comparator = comp;
+	}
+
+	@Override
+	public List<Action> search(Problem p) {
+		implementation.getNodeExpander().useParentLinks(true);
+		Node node = implementation.search(p, QueueFactory.<Node>createPriorityQueue(comparator));
+		return node == null ? SearchUtils.failure() : SearchUtils.getSequenceOfActions(node);
+	}
+	
+	@Override
+	public Object searchState(Problem p) {
+		implementation.getNodeExpander().useParentLinks(false);
+		Node node = implementation.search(p, QueueFactory.<Node>createPriorityQueue(comparator));
+		return node == null ? null : node.getState();
+	}
+
+	public Comparator<Node> getComparator() {
+		return comparator;
+	}
+
+	@Override
+	public NodeExpander getNodeExpander() {
+		return implementation.getNodeExpander();
+	}
+	
+	@Override
+	public Metrics getMetrics() {
+		return implementation.getMetrics();
+	}
 }