How do I set an object field in an array using reflection?

I am trying to write a function which takes an object as an argument and auto-fills it from some binary, using reflection on its class.

I've written some code that looks something like this (simplified):

for (Field f: obj.getClass().getDeclaredFields()) 
{
    try 
    {
        if (f.getType().isPrimitive())
        {
            Object value = getPrimitiveValue(f.getType());
            f.set(obj, value);
        }
        else if (f.getType().isArray())
        {
            Class<?> compType = f.getType().getComponentType();
            Vector<Object> container = new Vector<Object>();    

            for (int i = 0; i < SOME_ARRAY_SIZE; i++)
            {
                Object item = getPrimitiveValue(compType);
                container.add(item);
            }
        }

        object[] arr = container.toArray();
        f.set(obj, arr);  
    }
    catch (Exception e)
    {
        //...
    }
}

while getPrimitiveType reads from a static byte buffer a primitive type according to the component type.

the vector container is set with the correct values. If the component type is short, for instance, it becomes a short[] array.

However, the call f.set(obj, arr) which tries to set the value of the array field f to arr throws the exception: java.lang.IllegalArgumentException: Can not set [B field MyClass.myArrayField to [Ljava.lang.Object;

What is the correct way to do this?