框架中一些优雅的代码

一、Springboot 中 SpringApplication

1     public static List<String> loadFactoryNames(Class<?> factoryType, @Nullable ClassLoader classLoader) {
2         String factoryTypeName = factoryType.getName();
3         return (List)loadSpringFactories(classLoader).getOrDefault(factoryTypeName, Collections.emptyList());
4     }