List copy

In this chapter you will learn:

How to copy value from one list to another list
Copy Elements of ArrayList to Vector

Copy value to a List

static<T> void copy(List<? super T> dest, List<? extends T> src) Copies all of the elements from one list into another.

import java.util.Arrays;
import java.util.Collections;
import java.util.List;
/*  ja v a  2  s  .  com*/
public class Main {
  public static void main(String args[]) throws Exception {
    List list1 = Arrays.asList(new String[] { "U", "C" });
    List list2 = Arrays.asList(new String[] { "1", "2", "3" });

    System.out.println(list1);
    System.out.println(list2);

    Collections.copy(list2, list1);
    System.out.println(list1);
    System.out.println(list2);
  }
}

The output:

Copy Elements of ArrayList to Vector

The same copy methods can be used to copy from a list to a vector.

import java.util.ArrayList;
import java.util.Collections;
import java.util.Vector;
/*from ja v  a2 s.co m*/
public class Main {
  public static void main(String[] args) {

    ArrayList arrayList = new ArrayList();

    arrayList.add("1");
    arrayList.add("2");
    arrayList.add("3");
    arrayList.add("java2s.com");

    Vector v = new Vector();
    v.add("A");
    v.add("B");
    v.add("C");
    v.add("D");
    
    System.out.println("Before copy, Vector Contains : " + v);
    Collections.copy(v, arrayList);
    System.out.println("After Copy, Vector Contains : " + v);
  }
}