toarray

I've created a class called listItem and the following list: List<listItem> myList = new List<listItem>(); At some point in my code, I want to convert it to an array, thereby using: listItem[] myArray = myList.ToArray(); Unfortunately, this doesn't work, and I get this error message: Cannot convert [...] listItem[] to [...] List<listItem> I tried to figure this out, but very unsuccessfully... Thanks in advance. EDIT: My bad, the first code line I wrote was indeed mistyped! Actually, all the code above works pretty well. My error was due to the fact that my function: List<listItem> myFunction()

I defined List<Integer> stack = new ArrayList<Integer>(); When I'm trying to convert it to an array in the following way: Integer[] array= stack.toArray(); I get this exception: Exception in thread "main" java.lang.Error: Unresolved compilation problem: Type mismatch: cannot convert from Object[] to Integer[]. Why? It is exactly the same type- Integer to Integer. It's not like in this generic case when the classes are father-and-son relation I tried to do casting: Integer[] array= (Integer[]) stack.toArray(); But here I get this error: Exception in thread "main" java.lang.ClassCastException:

I was just looking at the method defined in the List interface: Returns an array containing all of the elements in this list in the correct order; the runtime type of the returned array is that of the specified array. If the list fits in the specified array, it is returned therein. Otherwise, a new array is allocated with the runtime type of the specified array and the size of this list. If the list fits in the specified array with room to spare (i.e., the array has more elements than the list), the element in the array immediately following the end of the collection is set to null. This is

I've got a List collection and I want to iterate over it in a multi threaded app. I need to protect it every time I iterate it since it could be changed and I don't want "collection was modified" exceptions when I do a foreach. What is the correct way to do this? Use lock every time I access or loop. I'm rather terrified of deadlocks. Maybe I'm just paranoid of using lock and shouldn't be. What do I need to know if I go this route to avoid deadlocks? Is lock fairly efficient? Use List<>.ToArray() to copy to an array each time I do a foreach. This causes a performance hit but is easy to do. I'm

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> {

The following code (run in android) always gives me a ClassCastException in the 3rd line: final String[] v1 = i18nCategory.translation.get(id); final ArrayList<String> v2 = new ArrayList<String>(Arrays.asList(v1)); String[] v3 = (String[])v2.toArray(); It happens also when v2 is Object[0] and also when there are Strings in it. Any Idea why? This is because when you use toArray() it returns an Object[], which can't be cast to a String[] (even tho the contents are Strings) This is because the toArray method only gets a List and not List<String> as generics are a source code only thing, and not