[Java] Convert ArrayList to array

//ArrayList generation
ArrayList<String> arrayList = new ArrayList<String>();
arrayList.add("A");
arrayList.add("B");
arrayList.add("C");

String[] array = (String[])arrayList.toArray();

System.out.println("ArrayList = " + arrayList.toString());
System.out.println("Array= " + Arrays.toString(array));

Exception in thread "main" java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [Ljava.lang.String;

//ArrayList generation
//Omission
System.out.println(arrayList.toArray().getClass());

class [Ljava.lang.Object;

//ArrayList generation
//Omission
//0 for the number of elements in the array or arrayList.size()Put in
String[] array = arrayList.toArray(new String[arrayList.size()]);
//String[] array = arrayList.toArray(new String[0]);* Processing will be slower (described later)

System.out.println("ArrayList = " + arrayList.toString());
System.out.println("Array= " + Arrays.toString(array));

ArrayList = [A, B, C]
Array= [A, B, C]

public <T> T[] toArray(T[] a) {
   if (a.length < size)
     return (T[]) Arrays.copyOf(elementData, size, a.getClass());
     System.arraycopy(elementData, 0, a, 0, size);
     if (a.length > size)
         a[size] = null;
     return a;
}

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