Added a few more utility functions to the nodes and iterators.

src/cu/edu/cujae/graphy/core/Node.java

@@ -18,6 +18,7 @@
  */
 package cu.edu.cujae.graphy.core;
 
+import java.util.Collection;
 import java.util.Set;
 
 /**
@@ -78,6 +79,13 @@ public interface Node<T> extends Cloneable
      */
     public Edge getAdjacentEdge(Node<T> v);
 
+    /**
+     * Returns a {@link Collection} containing all the adjacent vertices to this node.
+     *
+     * @return
+     */
+    public Collection<Integer> getAllAdjacentVertices();
+
     /**
      * Returns the set of edges connected to this node. If the node is isolated, it should return the empty set. This
      * set is an unmodifiable view of the {@link Node}'s internal container.

src/cu/edu/cujae/graphy/core/defaults/DefaultNode.java

@@ -20,11 +20,7 @@
 
 import cu.edu.cujae.graphy.core.Edge;
 import cu.edu.cujae.graphy.core.Node;
-import java.util.Collections;
-import java.util.Iterator;
-import java.util.LinkedHashMap;
-import java.util.Map;
-import java.util.Set;
+import java.util.*;
 import java.util.concurrent.CopyOnWriteArraySet;
 
 /**
@@ -110,6 +106,22 @@ public Edge getAdjacentEdge(Node<T> v)
         return getConnectionsFromVertex().get(v);
     }
 
+    @Override
+    public Collection<Integer> getAllAdjacentVertices()
+    {
+        Collection<Integer> nodes = new LinkedHashSet<>(getConnectionsFromVertex().size() + getConnectionsToVertex().size());
+        for (Edge e : getEdgesArrivingSelf())
+        {
+            nodes.add(e.getStartNode().getLabel());
+        }
+        for (Edge e : getEdgesDepartingSelf())
+        {
+            nodes.add(e.getFinalNode().getLabel());
+        }
+
+        return Collections.unmodifiableCollection(nodes);
+    }
+
     /**
      * {@inheritDoc}
      */