java - How do Singletons in Google App Engine (or more generally in a distributed server environment) work? -

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I find out how a singleton works in a Google app engine (or a distributed server environment). Your application may have to run simultaneously in multiple processes (on multiple machines), and the request can get a way out from the place, which is actually under the hood when an app does something like this: 'CacheManager .getInstance () '?

I am using only the GAE Cash Manager as an example, but I have to say that there is a single global application installation somewhere, so where is it? Is an RPC applicable? In fact, how is global application status (like sessions) generally controlled?

Regards, sine

App Engine is single-time per-time time in Java, not That per-webapp Their purpose is to provide the only point of access to the built-in service (which is both in the case of the cache and user API, is delivered through an RPC), but it is absolutely a design pattern for the library - a copy -Apple is not singleton Use these methods anywhere.


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