You can't find the High Sierra in App Store, and it is hidden from your purchased history on purpose by Apple. You can, however, open this link in Safari to download the High Sierra.High Sierra - Direct download link from the App Store
singleton Scopes the bean definition to a single instance per Spring container (default). prototype Allows a bean to be instantiated any number of times (once per use). request Scopes a bean definition to an HTTP request. Only valid when used with a web capable Spring context (such as with Spring MVC). session Scopes a bean definition to an HTTP session. Only valid when used with a webcapableSpring context (such as with Spring MVC). global-session Scopes a bean definition to a global HTTP session. Only valid when used in a portlet context.