ARTEMIS-1540 Missing management annotations

Some of the management operations are not properly annotated.
Also need to add an Operation to list divert names.

artemis-core-client/src/main/java/org/apache/activemq/artemis/api/core/Message.java

@@ -631,7 +631,9 @@ default Map<String, Object> toMap() {
    default Map<String, Object> toPropertyMap() {
       Map map = new HashMap<>();
       for (SimpleString name : getPropertyNames()) {
-         map.put(name.toString(), getObjectProperty(name.toString()));
+         //some property is SimpleString, which is not available for management console
+         Object value = getObjectProperty(name.toString());
+         map.put(name.toString(), value == null ? null : value.toString());
       }
       return map;
    }

artemis-core-client/src/main/java/org/apache/activemq/artemis/api/core/management/ActiveMQServerControl.java

@@ -591,6 +591,7 @@ void createQueue(@Parameter(name = "address", desc = "Address of the queue") Str
     * @return a textual summary of the queue
     * @throws Exception
     */
+   @Operation(desc = "Create a queue", impact = MBeanOperationInfo.ACTION)
    String createQueue(@Parameter(name = "address", desc = "Address of the queue") String address,
                     @Parameter(name = "routingType", desc = "The routing type used for this address, MULTICAST or ANYCAST") String routingType,
                     @Parameter(name = "name", desc = "Name of the queue") String name,
@@ -811,6 +812,7 @@ boolean closeConsumerWithID(@Parameter(desc = "The session ID", name = "sessionI
    @Operation(desc = "List all the connection IDs", impact = MBeanOperationInfo.INFO)
    String[] listConnectionIDs() throws Exception;
 
+   @Operation(desc = "List all producers", impact = MBeanOperationInfo.INFO)
    String listProducersInfoAsJSON() throws Exception;
 
    /**
@@ -1000,6 +1002,7 @@ void addAddressSettings(@Parameter(desc = "an address match", name = "addressMat
                            @Parameter(desc = "allow topics to be created automatically", name = "autoCreateAddresses") boolean autoCreateAddresses,
                            @Parameter(desc = "allow auto-created topics to be deleted automatically", name = "autoDeleteAddresses") boolean autoDeleteAddresses) throws Exception;
 
+   @Operation(desc = "Remove address settings", impact = MBeanOperationInfo.ACTION)
    void removeAddressSettings(@Parameter(desc = "an address match", name = "addressMatch") String addressMatch) throws Exception;
 
    /**
@@ -1011,6 +1014,15 @@ void addAddressSettings(@Parameter(desc = "an address match", name = "addressMat
    @Attribute(desc = "names of the diverts deployed on this server")
    String[] getDivertNames();
 
+   /**
+    * Jon plugin doesn't recognize an Operation whose name is in
+    * form getXXXX(), so add this one.
+    */
+   @Operation(desc = "names of the diverts deployed on this server", impact = MBeanOperationInfo.INFO)
+   default String[] listDivertNames() {
+      return getDivertNames();
+   }
+
    @Operation(desc = "Create a Divert", impact = MBeanOperationInfo.ACTION)
    void createDivert(@Parameter(name = "name", desc = "Name of the divert") String name,
                      @Parameter(name = "routingName", desc = "Routing name of the divert") String routingName,

artemis-core-client/src/main/java/org/apache/activemq/artemis/api/core/management/QueueControl.java

@@ -493,6 +493,7 @@ int changeMessagesPriority(@Parameter(name = "filter", desc = "A message filter
     * any other measure.
     * It is useful if you need the exact number of counts on a message
     */
+   @Operation(desc = "Flush internal executors", impact = MBeanOperationInfo.ACTION)
    void flushExecutor();
 
 }