Collections
Create List of n copies of an Object example
This is an example of how to create a List of n copies of an Object. We will use the nCopies(int n, T o)
API method of Collections. Creating a List of n copies of an Object implies that you should:
- Invoke the
nCopies(int n, T o)
API method of Collections. It returns an immutable List containing n copies of the specified Object. Its parameters are the number of elements in the returned list and the element to appear repeatedly in the returned list. In the example we use 5 copies of the String “element”. - Use an Iterator over the list to get all elements of the list.
Let’s take a look at the code snippet that follows:
package com.javacodegeeks.snippets.core; import java.util.Collections; import java.util.List; import java.util.Iterator; public class CreateListOfNCopies { public static void main(String[] args) { // static List nCopies(int n, Object obj) method returns immutable List containing n copies of the specified Object List list = Collections.nCopies(5,"element"); System.out.println("List elements : "); Iterator it = list.iterator(); while(it.hasNext()) System.out.println(it.next()); } }
Output:
List elements :
element
element
element
element
element
This was an example of how to a List of n copies of an Object in Java.