The toArray() method of ArrayList is used to return an array containing all the elements in ArrayList in the correct order.
Declaring toArray() method
public Object[] toArray()
or
public <T> T[] toArray(T[] a)
Parameters: This method either accepts no parameters or it takes an array T[] as a parameter which is the array into which the elements of the list are to be stored if it is big enough; otherwise, a new array of the same runtime type is allocated for this purpose.
Return Value: The function returns an array containing all the elements in this list.
Exception: The first overload of this method throws no exceptions. However, the second overload throws the following exceptions:
- ArrayStoreException: if the runtime type of the specified array is not a supertype of the runtime type of every element in this list.
- NullPointerException if the specified array is null
Examples of Java ArrayList.toArray() method
Example 1
Java
// Java Program to illustrate the// ArrayList toArray() method in JavaÂ
import java.util.*;Â
public class GFG {Â Â Â Â public static void main(String[] args)Â Â Â Â {Â
        // create object of ArrayList        ArrayList<Integer> ArrLis            = new ArrayList<Integer>();Â
        // Add elements        ArrLis.add(32);        ArrLis.add(67);        ArrLis.add(98);        ArrLis.add(100);Â
        // print ArrayList        System.out.println("ArrayList: " + ArrLis);Â
        // Get the array of the elements        // of the ArrayList        // using toArray() method        Object[] arr = ArrLis.toArray();Â
        System.out.println("Elements of ArrayList"                           + " as Array: "                           + Arrays.toString(arr));    }} |
Output
ArrayList: [32, 67, 98, 100] Elements of ArrayList as Array: [32, 67, 98, 100]
Example 2
Java
// Java Program to illustrate the// ArrayList toArray(T[]) method in JavaÂ
import java.util.*;Â
// Driver Classpublic class GFG {    // main function    public static void main(String[] args)    {        // create object of ArrayList        ArrayList<Integer> ArrLis            = new ArrayList<Integer>();Â
        // Add elements        ArrLis.add(32);        ArrLis.add(67);        ArrLis.add(98);        ArrLis.add(100);Â
        // print ArrayList        System.out.println(" ArrayList: " + ArrLis);Â
        // Get the array of the elements        // of the ArrayList        // using toArray(T[]) method        Integer arr[] = new Integer[ArrLis.size()];        arr = ArrLis.toArray(arr);Â
        System.out.println(" Elements of ArrayList "                           + "as Array: "                           + Arrays.toString(arr));    }} |
Output
ArrayList: [32, 67, 98, 100] Elements of ArrayList as Array: [32, 67, 98, 100]
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