Update Implementation AIGridGUI class

src/main/java/BattleShip/AIGridGUI.java

@@ -315,6 +315,26 @@ public class AIGridGUI extends JPanel {
             }
 
         }
+
+        //Mark the guess on the grid.
+
+        cellsGuessed[guessLocation] = true;
+        b = buttons.get(guessLocation);
+        s = b.getCellContents();
+        b.setBorder(loweredBevel);
+
+        if(s == null) {
+            //If no ship in that cell, mark as a miss.
+            text = "Other player missed. Your turn.";
+            b.setBackground(Color.BLUE);
+        } else {
+            //Check if guess killed a ship.
+            killed = s.counter();
+            if(killed) {
+                text = "Your " + s.getName() + " was sunk. Your turn.";
+                boolean unkilledCells = false;
+            }
+        }
     }
 
     //Return the location of a cell one space in the given direction, or return -1 if out of bounds.