Collection.toArray() java.lang.ClassCastException

Question

import java.util.HashMap;
import java.util.Map;


public class Main
{
    public static void main(String[] args)
    {
        Map map=new HashMap&l         


        

Answer 1

Change:

Class[] classes = (Class[]) map.values().toArray();

To:

Class[] classes = map.values().toArray(new Class[0]);

This gives information on which type of array to convert the Collection to. Otherwise, it returns an array of type Object (and that cannot be cast to an Class[]).

---

Quoted from the API documentation for Collection.toArray(T[] a):

Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array. ...
Note that toArray(new Object[0]) is identical in function to toArray().