Q:

Add a menu item within a menu within a menu item in JAVA

applicationMenu.add(subapplicationMenu);
    subapplicationMenu.add(item);
    subapplicationMenu.add(item1);
    subapplicationMenu.add(item2);

    item.add(item3);
    item.add(item4);
    item.add(item5);
    item.add(item6);
    item.add(item7);
    item.add(item8);
    item.add(item9);
    item.add(item10);
    item.add(item11);

    item1.add(item3);
    item1.add(item4);
    item1.add(item5);
    item1.add(item6);
    item1.add(item7);
    item1.add(item8);
    item1.add(item9);
    item1.add(item10);
    item1.add(item11);

    item2.add(item3);
    item2.add(item4);
    item2.add(item5);
    item2.add(item6);
    item2.add(item7);
    item2.add(item8);
    item2.add(item9);
    item2.add(item10);
    item2.add(item11);

I'm trying to add a menu item within a menu item within a menu item but it will not allow me to there are no errors it just will not show up when trying to access the third level of menu items. 

A:

You can nest JMenu within other instances of JMenu, and you can add a JMenuItem to a JMenu, but you can't add a JMenuItem to another JMenuItem.  Think about that... what did you expect that to do?  A leaf, for example, grows from a branch, not from another leaf. 
JMenu menu = new JMenu("Main Menu");

JMenu submenu = new JMenu("A menu within a menu");

JMenu subsubmenu = new JMenu("A menu within a menu within a menu");

JMenuItem itemFoo = new JMenuItem("Foo");
JMenuItem itemBar = new JMenuItem("Bar");
JMenuItem itemBaz = new JMenuItem("Baz");
JMenuItem itemQuz = new JMenuItem("Quz");

// These are OK

menu.add(subMenu);
subMenu.add(subsubmenu);
subMenu.add(itemFoo);
subMenu.add(itemBar);
subMenu.add(itemBaz);

// NO! 

itemBaz.add(itemQuz);

Review the tutorial.