Join two ArrayLists in Java
Given two ArrayLists in Java, the task is to join these ArrayLists.
Examples:
Input: ArrayList1: [Geeks, For, ForGeeks], ArrayList2: [GeeksForGeeks, A computer portal]
Output: ArrayList: [Geeks, For, ForGeeks, GeeksForGeeks, A computer portal]
Input: ArrayList1: [G, e, e, k, s], ArrayList2: [F, o, r, G, e, e, k, s]
Output: ArrayList: [G, e, e, k, s, F, o, r, G, e, e, k, s]
Approach: ArrayLists can be joined in Java with the help of Collection.addAll() method. This method is called by the destination ArrayList and the other ArrayList is passed as the parameter to this method. This method appends the second ArrayList to the end of the first ArrayList.
Syntax:
ArrayList1.addAll(ArrayList2);
Below is the implementation of the above approach:
import java.util.*;
public class GFG {
public static void main(String args[])
{
ArrayList<String>
list1 = new ArrayList<String>();
list1.add( "Geeks" );
list1.add( "For" );
list1.add( "ForGeeks" );
System.out.println( "ArrayList 1: "
+ list1);
ArrayList<String>
list2 = new ArrayList<String>();
list2.add( "GeeksForGeeks" );
list2.add( "A computer portal" );
System.out.println( "ArrayList 2: "
+ list2);
list1.addAll(list2);
System.out.println( "Joined ArrayLists: "
+ list1);
}
}
|
Last Updated :
11 Dec, 2018
Like Article
Save Article
Share your thoughts in the comments
Please Login to comment...