SpringMvc controller to returns JSON, displays error: HTTP status 406 - json

Question

I am learning spring 4.2.4 by writing some webapp code.The idea is to return json file by controller.
I have already posted my questions before couple of days ago and still no i could get the right suggestions for my case. I am trying all the suggestions given by stackoverfolow none of the suggestions could work for me. Here is my controller:
.....
#RequestMapping(value="/getmessages",method=RequestMethod.GET, produces="application/json")
#ResponseBody
public Map<String,Object> getMessage(Principal prinicipal){
List<Message>message=null;
if(prinicipal==null){
message=new ArrayList<Message>();
}
else{
String username=prinicipal.getName();
message=usersService.getMessage(username);
}
Map<String,Object> data= new HashMap<String,Object>();
data.put("message", message);
data.put("number", message.size());
System.out.println("message has to be her\n"+message);
System.out.println("Number message has to be her is..."+message.size());
return data;
}
the message content which is to be retrieved from mysql is propely displayed in console.
The problem is conversion to JSON and return the result. I have been trying by change the jackson 1.9.x jar to jackson-fasterxml-2.x and it does not work. All other possible configuration of servlete also does not work for me.
When I add jackson-fasterxml-databind ....it displays file download dialogue box for filename"getmessages". to download and save...
I am very grateful for your help.

Answer 1

Finally I have solved this problem as follow:
I changed my return type from MAP to String and I converted my MAP to String in side my CONTROLLER as:
Converting my Map to String:
ObjectMapper mapper = new ObjectMapper();
String jsonFromMap = mapper.writeValueAsString(data);
I have also changed my dependencies as:
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.2.3</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.2.3</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.2.3</version>
Inside #RequestMapping change
produces=application/json
to
produces=text/html
I think the problem is with browser unable to understand application/json and returning Map............
Any how I did what I want to do even-though I do not know how I did it!