Added previousMenu function to Menu and did refactoring

src/main/java/Application/Menu.java

@@ -5,14 +5,17 @@ import java.util.ArrayList;
 public class Menu {
 
     private String name;
+    private Menu previousMenu;
     private ArrayList<Menu> subMenuList;
 
     public Menu(String name){
         setName(name);
+        setPreviousMenu(null);
         subMenuList = new ArrayList<>();
     }
 
     public void addMenu(Menu menu){
+        menu.setPreviousMenu(this);
         subMenuList.add(menu);
     }
 
@@ -24,7 +27,19 @@ public class Menu {
         this.name = name;
     }
 
+    public Menu getMenu(int i){
+        return getSubMenuList().get(i);
+    }
+
     public ArrayList<Menu> getSubMenuList() {
         return this.subMenuList;
     }
+
+    private void setPreviousMenu(Menu menu){
+        this.previousMenu = menu;
+    }
+
+    public Menu getPreviousMenu(){
+        return this.previousMenu;
+    }
 }

src/test/java/Application/MenuTest.java

@@ -6,12 +6,22 @@ import org.junit.jupiter.api.Test;
 
 import java.util.ArrayList;
 
-import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 class MenuTest {
 
+    Menu rootMenu;
+
     @BeforeEach
     void setUp() {
+        rootMenu = new Menu("Root");
+        Menu menu1 = new Menu("Menu1");
+        Menu menu2 = new Menu("Menu2");
+        Menu menu1_1 = new Menu("Menu1.1");
+        menu1.addMenu(menu1_1);
+        rootMenu.addMenu(menu1);
+        rootMenu.addMenu(menu2);
     }
 
     @AfterEach
@@ -19,20 +29,18 @@ class MenuTest {
     }
 
     @Test
-    void testCorrectName(){
-        Menu menu = new Menu("Item 1");
-        assertTrue(menu.getName().equals("Item 1"));
+    void testCorrectName() {
+        assertEquals("Root", rootMenu.getName());
     }
 
     @Test
-    void testAddMenuFunction(){
-        ArrayList<Menu> menus = new ArrayList<>();
-        Menu menu1 = new Menu("Menu 1");
-        Menu menu2 = new Menu("Menu 2");
-        Menu menu1_1 = new Menu("Menu 1.1");
-        menu1.addMenu(menu1_1);
-        menus.add(menu1);
-        menus.add(menu2);
-        assertTrue(menus.get(0).equals(menu1) && menus.get(1).equals(menu2) && menus.get(0).getSubMenuList().get(0).equals(menu1_1));
+    void testAddMenuFunction() {
+        assertTrue(rootMenu.getMenu(0).getName().equals("Menu1") && rootMenu.getMenu(1).getName().equals("Menu2") && rootMenu.getMenu(0).getMenu(0).getName().equals("Menu1.1"));
     }
+
+    @Test
+    void testPreviousMenuFunction(){
+        assertTrue(rootMenu.getPreviousMenu() == null && rootMenu.getMenu(0).getPreviousMenu().getName().equals("Root") && rootMenu.getMenu(0).getMenu(0).getPreviousMenu().getName().equals("Menu1"));
+    }
+
 }