/*
Copy Elements of One Java ArrayList to Another Java ArrayList Example
This java example shows how to copy all elements of one Java ArrayList object to
another Java ArrayList object using copy method of Collections class.
*/
import java.util.ArrayList;
import java.util.Collections;
public class CopyElementsOfArrayListToArrayListExample {
public static void main(String[] args) {
//create first ArrayList object
ArrayList arrayList1 = new ArrayList();
//Add elements to ArrayList
arrayList1.add("1");
arrayList1.add("2");
arrayList1.add("3");
//create another ArrayList object
ArrayList arrayList2 = new ArrayList();
//Add elements to Arraylist
arrayList2.add("One");
arrayList2.add("Two");
arrayList2.add("Three");
arrayList2.add("Four");
arrayList2.add("Five");
/*
To copy elements of one Java ArrayList to another use,
static void copy(List dstList, List sourceList) method of Collections class.
This method copies all elements of source list to destination list. After copy
index of the elements in both source and destination lists would be identical.
The destination list must be long enough to hold all copied elements. If it is
longer than that, the rest of the destination list's elments would remain
unaffected.
*/
System.out.println("Before copy, Second ArrayList Contains : " + arrayList2);
//copy all elements of ArrayList to another ArrayList using copy method of Collections class
Collections.copy(arrayList2,arrayList1);
/*
Please note that, If destination ArrayList object is not long enough to hold all
elements of source ArrayList, it throws IndexOutOfBoundsException.
*/
System.out.println("After copy, Second ArrayList Contains : " + arrayList2);
}
}
/*
Output would be
Before copy, Second ArrayList Contains : [One, Two, Three, Four, Five]
After copy, Second ArrayList Contains : [1, 2, 3, Four, Five]
*/
