Today, I will share a very basic Java program that converts an ArrayList to array. For most Java developers this is a routine task, but many new comers to Java have asked me this question of how to convert an array to ArrayList. Here is the example code.





import java.util.*;
public class ArrayToArrayList{
   public static void main(String args[]){
     //Create an ArrayList of Strings.
    ArrayList list = new ArrayList();
    //Populate the ArrayList.
    list.add("A1");
    list.add("A2");
    list.add("A3");
    list.add("A4");
    list.add("A5");
    list.add("A6");
    /*Initialize a String array. 
    Set array's capacity equal to ArrayList size*/
    String[] array = new String[list.size()];
    //Now get the array from ArrayList. There is no magic here. 
   //We are calling toArray method of the ArrayList class.     	
   array = list.toArray(array);
   }
}


How to convert a Java Array to a List

In some instances you may need to convert an array to a list. This is also a simple task. Using the array variable defined in the example above, we can call asList method of the Arrays class to get a List variable from the array.

	List  list2 = Arrays.asList(array);


Enjoy!

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