setStat docs

src/GomokuCell.java

@@ -35,8 +35,8 @@ public class GomokuCell{
     }
     
     /**
-     * Return neighbour.
-     * @return The EnumMap of neighbour.
+     * Return neighbours.
+     * @return The EnumMap of neighbours.
      */
     public EnumMap<Cardinal, GomokuCell> getAllNeighbour(){
         return neighbour;
@@ -53,7 +53,9 @@ public class GomokuCell{
     //------------------Sets--------------------------
     
     /**
-     *
+     * Change state of the current cell.
+     * @param c The color of the token played.
+     * @throws IllegalStateException If the cell is not playable.
      */
     public void setState(Color c){
         if (!this.isPlayable())
@@ -86,7 +88,8 @@ public class GomokuCell{
      */
     public boolean isPlayable(){
         for (Cardinal c : Cardinal.values()) {
-            if (this.getNeighbour(c).isPlayed()) return true;
+            GomokuCell current = this.getNeighbour(c);
+            if (current != null && current.isPlayed()) return true;
         }
         return false;
     }