Clarify what the ExternallyProvidedVertxService purpose is

Author: Sanne

hibernate-reactive-core/src/main/java/org/hibernate/reactive/service/ExternallyProvidedVertxService.java

@@ -0,0 +1,28 @@
+package org.hibernate.reactive.service;
+
+import io.vertx.core.Vertx;
+
+import java.util.Objects;
+
+/**
+ * If the framework / container / runtime already has a Vert.x instance which
+ * it wants to reuse, use this VertxService implementation to inject it into
+ * Hibernate Reactive registry at boot time.
+ * When using this service, Hibernate will not reconfigure nor stop the
+ * Vert.x instance on shutdown as this responsibility belongs to the
+ * code managing it.
+ */
+public final class ExternallyProvidedVertxService implements VertxService {
+
+    private final Vertx vertx;
+
+    public ExternallyProvidedVertxService(Vertx vertx) {
+        Objects.requireNonNull( vertx );
+        this.vertx = vertx;
+    }
+
+    @Override
+    public Vertx getVertx() {
+        return vertx;
+    }
+}

hibernate-reactive-core/src/main/java/org/hibernate/reactive/service/ManagedVertxService.java

@@ -1,7 +1,7 @@
 package org.hibernate.reactive.testing;
 
 import io.vertx.core.Vertx;
-import org.hibernate.reactive.service.ManagedVertxService;
+import org.hibernate.reactive.service.ExternallyProvidedVertxService;
 import org.hibernate.reactive.service.VertxService;
 import org.hibernate.service.Service;
 import org.hibernate.service.ServiceRegistry;
@@ -35,10 +35,10 @@ public ServiceRegistryImplementor getServiceRegistry() {
     //TODO extract into its own class and evolve as necessary?
     private static class Registry implements ServiceRegistryImplementor {
 
-        private final ManagedVertxService vertxService;
+        private final ExternallyProvidedVertxService vertxService;
 
         public Registry(Vertx vertx) {
-            this.vertxService = new ManagedVertxService( vertx );
+            this.vertxService = new ExternallyProvidedVertxService( vertx );
         }
 
         @Override