Question

I want to display a tree view in my page. For that i will have a List object. List object will contain some more list objects. I don’t know how many nested levels i will get. So please tell me, how to navigate through the list.

Sample data i want to display is

• Education

  • Mathematics
    • Trigonometry
  • Science
    • Physics
      • nuclear physics
    • chemistry
  • Social

• Sports

  • cricket
  • foot ball
• Technology
  • mobiles
  • computers
    • laptops
    • pc

Answer 1

You need a recursive method as shown below :

void printList(Collection myList) {
   for(Object o : myList) {
      if (Collection.class.isAssignableFrom(o.getClass())) {
          printList((Collection)o);
      }
      else {
          print o;
      }
  }
}