Question

I have a java method that should check through an ArrayList and check if it contains an instance of a given class. I need to pass the method the type of class to check for as a parameter, and if the List contains an object of the given type, then return it.

Is this achievable?

Answer 1

public static <T> T find(Collection<?> arrayList, Class<T> clazz)
{
    for(Object o : arrayList)
    {
        if (o != null && o.getClass() == clazz)
        {
            return clazz.cast(o);
        }
    }

    return null;    
}

and call

String match = find(myArrayList, String.class);