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https://issues.apache.org/jira/browse/JENA-1029?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14803229#comment-14803229
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Andy Seaborne commented on JENA-1029:
-------------------------------------
This is only a simple bootstrap for Jena itself and in no way replaces CDI or
OGSi. (I have not used CDI.)
It does need to work with just jars on the classpath and Java SE.
Do you have a specific proposal? How would the proposal above need to differ
for different implementations?
> Add a Jena-wide subsystem lifecycle
> -----------------------------------
>
> Key: JENA-1029
> URL: https://issues.apache.org/jira/browse/JENA-1029
> Project: Apache Jena
> Issue Type: Improvement
> Affects Versions: Jena 3.0.0
> Reporter: Andy Seaborne
>
> A subsystem lifecyclefor Jena would provide the hook for:
> * basic wiring together e.g. wiring RIOT into Jena core
> * initialization e.g. {{TDB.init()}} becomes redundant
> * starting and stopping in large systems, e.g. starting and stopping Fuseki2
> when in a Tomcat server
> This proposal is as simple as possible. It is for system bootstrap and basic
> lifecycle. It is not intended to work for a mixture of jars from different
> Jena releases.
> *Sub-system Interface*
> {code:title=JenaSubsystemLifecycle|borderStyle=solid}
> public interface JenaSubsystemLifecycle {
> public void start() ;
> public void stop() ;
> }
> {code}
> {{stop}} would not be called normally as part of JVM exit (code can do that
> itself anyway). It is in support of start-stop-(re)start and only called if
> there is a hook for such a cycle. {{stop}} is more of a placeholder for the
> moment.
> *Registry*
> There is a single registry:
> {code:title=JenaSubsystemRegistry|borderStyle=solid}
> public class JenaSubsystemRegistry {
> public static void add(JenaSubsystemLifecycle module) ;
> public static boolean isRegistered(JenaSubsystemLifecycle module) ;
> public static void remove(JenaSubsystemLifecycle module) ;
> public static int size() ;
> public static boolean isEmpty() ;
> public static void forEach(Consumer<JenaSubsystemLifecycle> action) ;
> }
> {code}
> *Ensuring initialization*
> Jena core provides a "system init" that is cheap to call if initialization
> has already occurred. It should attempt the first call as early as possible.
> When initializing, it runs a {{ServiceLoader}} cycle to discover any
> {{JenaSubsystemLifecycle}} implementations described in a
> {{META-INF/services/...}} file and populates the registry. Then the registry
> is
> used to call {{start()}} in some unspecified order.
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