2d Arraylist java example

In this post, we will see how to create 2d Arraylist in java.

Best way to create 2d Arraylist is to create list of list in java.

List<List> arraylist2D = new ArrayList<List>();

Let’s create a program to implement 2d Arraylist java.

package org.arpit.java2blog;

import java.util.ArrayList;
import java.util.List;

public class Java2DArrayListMain {

public static void main(String[] args) {

// Intialize the arraylist
List<List> arraylist2D = new ArrayList<List>();

// Create first list
List list1=new ArrayList();
list1.add("List1_Str1");
list1.add("List1_Str2");
list1.add("List1_Str3");

// Create second list
List list2=new ArrayList();
list2.add("List2_Str1");
list2.add("List2_Str2");
list2.add("List2_Str3");

// Create third list
List list3=new ArrayList();
list3.add("List3_Str1");
list3.add("List3_Str2");
list3.add("List3_Str3");
list3.add("List3_Str4");

// Add individual list to arraylist2D
arraylist2D.add(list1);
arraylist2D.add(list2);
arraylist2D.add(list3);

//Let's retrieve element from the arraylist2D.
System.out.println("2nd element in list3 : "+arraylist2D.get(2).get(1));
System.out.println("3nd element in list1 : "+arraylist2D.get(0).get(2));
System.out.println("1st element in list2 : "+arraylist2D.get(1).get(0));
}
}

Output:

That’s all about 2d Arraylist java.