// collectiontopics/FillingLists.java // (c)2021 MindView LLC: see Copyright.txt // We make no guarantees that this code is fit for any purpose. // Visit http://OnJava8.com for more book information. // Collections.fill() & Collections.nCopies() import java.util.*; class StringAddress { private String s; StringAddress(String s) { this.s = s; } @Override public String toString() { return super.toString() + " " + s; } } public class FillingLists { public static void main(String[] args) { List list = new ArrayList<>( Collections.nCopies(4, new StringAddress("Hello"))); System.out.println(list); Collections.fill(list, new StringAddress("World!")); System.out.println(list); } } /* Output: [StringAddress@19e0bfd Hello, StringAddress@19e0bfd Hello, StringAddress@19e0bfd Hello, StringAddress@19e0bfd Hello] [StringAddress@139a55 World!, StringAddress@139a55 World!, StringAddress@139a55 World!, StringAddress@139a55 World!] */