Question

I am trying to do this

List<String> stringList = new ArrayList<String>();
stringList.add("one");
stringList.add("two");
stringList.add("three");

(String[]) stringList.toArray();

why does this gives me class cast exception ?

Caused by: java.lang.ClassCastException: [Ljava.lang.Object;

Answer 1

Better try this other method:

String[] stringArray = stringList.toArray(new String[stringList.size()]);

In that way the array returned is of the exact type that you need, no cast needed. The method you’re invoking returns an Object[], not a String[] and the cast you’re trying to perform is invalid.