Determine the actual type of a method's first parameter at runtime when that parameter is generic.

RuntimeTypeHelper.java

    public static Class<?> getTypeOfFirstParameter( final Method method )
    {
        final Type type = method.getGenericParameterTypes()[0];

        // Now get the parametrized type of the generic.
        if (!(type instanceof ParameterizedType))
        {
            return method.getParameterTypes()[0];
        }

        final ParameterizedType pType = (ParameterizedType) type;

        final Type t = pType.getActualTypeArguments()[0];

        if (t instanceof Class) {
            return (Class<?>) t;
        }

        return null;
    }