need one more abstract class

src/main/java/model/Cell.java

-package model;
-
-import util.Position;
-
-import java.util.List;
-
-public class Cell implements State, Board{
-    Position position;
-    public Cell(Position position){
-        this.position = position;
-    }
-    @Override
-    public boolean isOnFire(Position position) {
-        return false;
-    }
-
-    @Override
-    public Object getState(Position position) {
-        return null;
-    }
-
-    @Override
-    public void setState(Object state, Position position) {
-
-    }
-
-    @Override
-    public int rowCount() {
-        return 0;
-    }
-
-    @Override
-    public int columnCount() {
-        return 0;
-    }
-
-    @Override
-    public List<Position> updateToNextGeneration() {
-        return null;
-    }
-
-    @Override
-    public void reset() {
-
-    }
-
-    @Override
-    public int stepNumber() {
-        return 0;
-    }
-}

src/main/java/model/Cloud.java

@@ -2,11 +2,17 @@ package model;
 
 import util.Position;
 
+import java.util.List;
 import java.util.Random;
 
-public class Cloud {
+public class Cloud implements Extinguish{
     private final Random randomGenerator = new Random();
     private Position randomPosition() {
         return new Position(randomGenerator.nextInt(rowCount), randomGenerator.nextInt(columnCount));
     }
+
+    @Override
+    public List<Position> updatePosition() {
+        return null;
+    }
 }

src/main/java/model/Extinguish.java

 package model;
 
+import util.Position;
+
+import java.util.List;
+
 public interface Extinguish {
+    List<Position> updatePosition();
+    List<Position> neighbors();
+    List<Position> getPosition();
+    List<Position> setPosition();
 
 }

src/main/java/model/FireFighter.java

@@ -5,7 +5,7 @@ import util.Position;
 import java.util.List;
 import java.util.Set;
 
-public class FireFighter {
+public class FireFighter implements Extinguish{
     private final int initialFirefighterCount;
     private List<Position> firefighterPositions;
     private Set<Position> firePositions;
@@ -13,4 +13,8 @@ public class FireFighter {
         return new Position(randomGenerator.nextInt(rowCount), randomGenerator.nextInt(columnCount));
     }
 
+    @Override
+    public List<Position> updatePosition() {
+        return null;
+    }
 }

src/main/java/model/Grid.java

+package model;
+
+import java.util.Random;
+
+public class Grid {
+    private final int columnCount;
+    private final int rowCount;
+    public Grid(int row,int column){
+        this.columnCount = column;
+        this.rowCount = row;
+    }
+    private final Random randomGenerator = new Random();
+    //ham de lay trang thai cua tung vi tri ban dau
+    //ham update vi tri sau khi da dap lua
+    //ham dap lua:xet vi tri lua;vi tri dia ly, quyet dinh phuong thuc dap lua
+
+}

src/main/java/model/Mobile.java

+package model;
+
+import util.Position;
+
+import java.util.List;
+
+public class Mobile implements Extinguish{
+    @Override
+    public List<Position> updatePosition() {
+        return null;
+    }
+}

src/main/java/model/Moutain.java

+package model;
+
+import util.Position;
+
+import java.util.List;
+
+public class Moutain implements StablePosition{
+    @Override
+    public List<Position> stablePosition() {
+        return null;
+    }
+}

src/main/java/model/Road.java

+package model;
+
+import util.Position;
+
+import java.util.List;
+
+public class Road implements StablePosition{
+    @Override
+    public List<Position> stablePosition() {
+        return null;
+    }
+}

src/main/java/model/Rocks.java

+package model;
+
+import util.Position;
+
+import java.util.List;
+
+public class Rocks implements StablePosition{
+    @Override
+    public List<Position> stablePosition() {
+        return null;
+    }
+}

src/main/java/model/StablePosition.java

+package model;
+import util.Position;
+
+import java.util.*;
+public interface StablePosition {
+    List<Position> stablePosition();
+}

src/main/java/model/Terrain.java

+package model;
+
+import util.Position;
+
+import java.util.List;
+
+public class Terrain implements StablePosition{
+    @Override
+    public List<Position> stablePosition() {
+        return null;
+    }
+}