broker/Server: ScheduledExecutorService moved from MapDBPersistentStore

broker/ProtocolProcessorBootstrapper: tabs removed
broker/MapDBPersistentStore: bonding to Server removed

broker/src/main/java/io/moquette/server/Server.java

@@ -45,6 +45,9 @@ import java.io.IOException;
 import java.util.Collections;
 import java.util.List;
 import java.util.Properties;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+
 import static io.moquette.logging.LoggingUtils.getInterceptorIds;
 
 /**
@@ -68,6 +71,8 @@ public class Server {
 
     private ProtocolProcessorBootstrapper m_processorBootstrapper;
 
+    private ScheduledExecutorService scheduler;
+
     public static void main(String[] args) throws IOException {
         final Server server = new Server();
         server.startServer();
@@ -172,6 +177,8 @@ public class Server {
         }
         LOG.info("Starting Moquette Server. MQTT message interceptors = {}.", getInterceptorIds(handlers));
 
+        scheduler = Executors.newScheduledThreadPool(1);
+
         final String handlerProp = System.getProperty(BrokerConstants.INTERCEPT_HANDLER_PROPERTY_NAME);
         if (handlerProp != null) {
             config.setProperty(BrokerConstants.INTERCEPT_HANDLER_PROPERTY_NAME, handlerProp);
@@ -270,6 +277,9 @@ public class Server {
                 LOG.warn("The embedded Hazelcast instance is already shut down.");
             }
         }
+
+        scheduler.shutdown();
+
         LOG.info("The Moquette server has been stopped.");
     }
 
@@ -332,4 +342,8 @@ public class Server {
     public ProtocolProcessor getProcessor() {
         return m_processor;
     }
+    
+    public ScheduledExecutorService getScheduler() {
+        return scheduler;
+    }
 }