context.getType can be null the following fixes the detectDialogFactories Method

private void detectDialogFactories() throws RepositoryException {
WebApplicationContext context = getWebApplicationContext();
String[] beanDefinitionNames = context.getBeanDefinitionNames();
for (String beanDefinitionName : beanDefinitionNames) {
Class<?> type = context.getType(beanDefinitionName);
if (type!=null && type.isAnnotationPresent(DialogFactory.class))

}
}