加載 META-INF/services/ 下文件的兩種方式

1、spi

ServiceLoader<SpiService> load = ServiceLoader.load(ServletContainerInitializer.class);

2、

/*Class<T> serviceType;
String configFile = SERVICES + serviceType.getName();*/
String configFile = "META-INF/services/javax.servlet.ServletContainerInitializer";
Enumeration<URL> resources = ClassLoader.getSystemResources(configFile);
while (resources.hasMoreElements()) {
    parseConfigFile(containerServicesFound, resources.nextElement());
}