Why Servlet.getContext(String) does not return null after undeploy

The parameter to ServletContext#getContext does not need to point to the exact URI of the context. Therefore:

all strings that start with /app1 will give you the context for the /app1 application,
all strings that start with /app2 will give you the context for the /app2 application,
after you stop /app2, all requests for /app2 will be routed to the ROOT context. Therefore getContext("/app2") will return the ROOT context.

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