diff --git a/broker/src/main/java/io/moquette/server/netty/NettyAcceptor.java b/broker/src/main/java/io/moquette/server/netty/NettyAcceptor.java
index 1eaa6f36..7aa98725 100644
--- a/broker/src/main/java/io/moquette/server/netty/NettyAcceptor.java
+++ b/broker/src/main/java/io/moquette/server/netty/NettyAcceptor.java
@@ -276,8 +276,8 @@ public class NettyAcceptor implements ServerAcceptor {
         if (m_bossGroup == null) {
             throw new IllegalStateException("Invoked close on an Acceptor that wasn't initialized");
         }
-        Future workerWaiter = m_workerGroup.shutdownGracefully();
-        Future bossWaiter = m_bossGroup.shutdownGracefully();
+        Future<?> workerWaiter = m_workerGroup.shutdownGracefully();
+        Future<?> bossWaiter = m_bossGroup.shutdownGracefully();
 
         try {
             workerWaiter.await(100);
diff --git a/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java b/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java
index ef907062..008953c8 100644
--- a/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java
+++ b/broker/src/main/java/io/moquette/spi/impl/ProtocolProcessor.java
@@ -460,6 +460,8 @@ public class ProtocolProcessor {
             case EXACTLY_ONCE:
                 this.qos2PublishHandler.receivedPublishQos2(channel, msg);
                 break;
+            default:
+            	break;
         }
     }
 
diff --git a/broker/src/main/java/io/moquette/spi/impl/security/AuthorizationsCollector.java b/broker/src/main/java/io/moquette/spi/impl/security/AuthorizationsCollector.java
index 34b7798f..9db32b6e 100644
--- a/broker/src/main/java/io/moquette/spi/impl/security/AuthorizationsCollector.java
+++ b/broker/src/main/java/io/moquette/spi/impl/security/AuthorizationsCollector.java
@@ -35,9 +35,9 @@ class AuthorizationsCollector implements IAuthorizator {
 
     private static final Logger LOG = LoggerFactory.getLogger(AuthorizationsCollector.class);
 
-    private List<Authorization> m_globalAuthorizations = new ArrayList();
-    private List<Authorization> m_patternAuthorizations = new ArrayList();
-    private Map<String, List<Authorization>> m_userAuthorizations = new HashMap();
+    private List<Authorization> m_globalAuthorizations = new ArrayList<>();
+    private List<Authorization> m_patternAuthorizations = new ArrayList<>();
+    private Map<String, List<Authorization>> m_userAuthorizations = new HashMap<>();
     private boolean m_parsingUsersSpecificSection = false;
     private boolean m_parsingPatternSpecificSection = false;
     private String m_currentUser = "";
@@ -59,7 +59,7 @@ class AuthorizationsCollector implements IAuthorizator {
         if (m_parsingUsersSpecificSection) {
             //TODO in java 8 switch to m_userAuthorizations.putIfAbsent(m_currentUser, new ArrayList());
             if (!m_userAuthorizations.containsKey(m_currentUser)) {
-                m_userAuthorizations.put(m_currentUser, new ArrayList());
+                m_userAuthorizations.put(m_currentUser, new ArrayList<Authorization>());
             }
             List<Authorization> userAuths = m_userAuthorizations.get(m_currentUser);
             userAuths.add(acl);
diff --git a/broker/src/main/java/io/moquette/spi/impl/subscriptions/SubscriptionsStore.java b/broker/src/main/java/io/moquette/spi/impl/subscriptions/SubscriptionsStore.java
index c0f1c9b2..40d0d977 100644
--- a/broker/src/main/java/io/moquette/spi/impl/subscriptions/SubscriptionsStore.java
+++ b/broker/src/main/java/io/moquette/spi/impl/subscriptions/SubscriptionsStore.java
@@ -247,7 +247,7 @@ public class SubscriptionsStore {
         return visitor.getResult();
     }
     
-    private void bfsVisit(TreeNode node, IVisitor visitor, int deep) {
+    private void bfsVisit(TreeNode node, IVisitor<?> visitor, int deep) {
         if (node == null) {
             return;
         }