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I was just looking at the method defined in the List interface: <T> T[] toArray(T[] a) , and I have a question. Why is it generic? Because of that fact, method is not complete type-safe. The following code fragment compiles but causes ArrayStoreException : List<Integer> list = new ArrayList<Integer>(); list.add(1); list.add(2); String[] stringArray = list.toArray(new String[]{}); It seems to me if toArray was not generic and took List type parameter, it would be better. I have written toy example and it is ok witout generic: package test; import java.util.Arrays; public class TestGenerics<E> { private Object[] elementData = new Object[10]; private int size = 0; public void add(E e) { elementData[size++] = e; } @SuppressWarnings("unchecked") //I took this code from ArrayList but it is not generic public E[] toArray(E[] a) { if (a.length < size) // Make a new array of a's runtime type, but my contents: return (E[]) Arrays.copyOf(elementData, size, a.getClass()); System.arraycopy(elementData, 0, a, 0, size); if (a.length > size) a[size] = null; return a; } public static void main(String[] args) { TestGenerics<Integer> list = new TestGenerics<Integer>(); list.add(1); list.add(2); list.add(3); //You don't have to do any casting Integer[] n = new Integer[10]; n = list.toArray(n); } } Is there any reason why it is declared that way?

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