getNeighbours done

countAliveNeighbours done
calculateNextState done
calculateNextStates done

Grid.java

 import java.util.*;
 
+import static com.sun.tools.doclint.Entity.ne;
+import static com.sun.tools.doclint.Entity.or;
+
 /**
  * {@code Grid} instances represent the grid in <i>The Game of Life</i>.
  */
@@ -95,11 +98,22 @@ public class Grid implements Iterable<Cell> {
     }
 
     private boolean[][] calculateNextStates() {
-        return null;
+        boolean[][] nextStates = new boolean[numberOfRows][numberOfColumns];
+        for (Cell cell : this) {
+            for (int i = 0; i == numberOfRows - 1; i++) {
+                for (int j = 0; j == numberOfColumns - 1; j++) {
+                    nextStates[i][j] = calculateNextState(i, j, cell);
+                }
+            }
+        }
+        return nextStates;
     }
 
     private boolean calculateNextState(int rowIndex, int columnIndex, Cell cell) {
-	return false;
+        if (cell.isAlive()) {
+            return (countAliveNeighbours(rowIndex, columnIndex) == 2) || (countAliveNeighbours(rowIndex, columnIndex) == 3);
+        }
+        else return false;
     }
 
     private int countAliveNeighbours(int rowIndex, int columnIndex) {
@@ -125,6 +139,11 @@ public class Grid implements Iterable<Cell> {
     }
 
     private void goToNextState(boolean[][] nextState) {
+        Iterator<Cell> iterator = iterator();
+        while (iterator.hasNext()) {
+            Cell cell = iterator.next();
+            cell.isAlive() = nextState[][];
+        }
     }
 
     /**