Create Enumeration of objects

Question

I need to create a java.util.Enumeration of Fruit objects so that I can pass it to this method during my test. It's a legacy code and I cannot change method signature.

public void get(Enumeration<Fruit> fruits){}

My fruit class:

public class Fruit{
    String name;
    //getters and setters   
}

How can I create an Enumeration of Fruit objects?

Answer 1

You can use the Collections.enumeration(Collection<T>) method to convert a collection, such as a List<Fruit>, to Enumeration<Fruit>:

List<Fruit> fruits = new ArrayList<>();
fruits.add(new Fruit());
Enumeration<Fruit> fruitEnumeration = Collections.enumeration(fruits);

Answer 2

You can use Collections.enumeration() to convert from a Collection<T> (which includes List<T>) to an Enumeration<T>. An example (blatantly stolen from here):

package com.tutorialspoint;

import java.util.*;

public class CollectionsDemo {
   public static void main(String args[]) {
       // create an ArrayList
       List arrayList = new ArrayList();

       // populate the list
       arrayList.add("A");
       arrayList.add("B");
       arrayList.add("C");  

       // create an Enumeration
       Enumeration e = Collections.enumeration(arrayList);

       System.out.println("Printing the enumeration:");

       while (e.hasMoreElements()) {
            System.out.println("Value is: " + e.nextElement());
       }
   }    
}