将嵌套类的java对象转换为Json

我一直在尝试从具有嵌套类的java对象/类创建json。但是只有*类在Json中输出。我想从Web服务应用程序返回json，或者将json转换为具有嵌套类的java对象

I have been trying to create json from a java object / class that has a nested class. However only the top level class is output in Json. I want to return json from a web services application or alternatively covert json to a java object with nested classes

public class JsonData {
    static String firstName;
    static String lastName;
    static String streetName;
    static String cityName;
    static String stateName;

    static PersonalInfo personalInfo = new PersonalInfo(); 

 //  typical set and get followed by the nested class
     static class PersonalInfo {
     String height;
     String weight;
     String eyeColor;
     String favoriteColor;
     // getter's and setters for this class
     }
   }

    // in a separate method that handles the web service request set the values... 

   @RequestMapping(value = "/json", method = RequestMethod.GET)
public @ResponseBody String sendJsonSample() throws JsonGenerationException {
    ObjectMapper jsonMapper = new ObjectMapper();
    System.out.println("\nReceived Request for json data what happens now ! \n");
    JsonData jsonData = new JsonData();
    jsonData.setCityName("New York");
    jsonData.setFirstName("Fred");
    jsonData.setLastName("Smith");
    jsonData.setStateName("NY");
    jsonData.setStreetName("Broadway");
    JsonData.personalInfo.setEyeColor("Green");
    JsonData.personalInfo.setFavoriteColor("Yellow");
    JsonData.personalInfo.setHeight("SixFeet");
    JsonData.personalInfo.setWeight("180");

      // now convert to json with the following
      try {
        String json = jsonMapper.writeValueAsString(jsonData);
        return json;
      } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        }       
      return "ERROR"
     }

    // if I use a browser to my controller http://localhost:8080/json the json returned to my web services call only includes the top or outer level class 
    {
      stateName: "NY",
      firstName: "Fred",
      lastName: "Smith",
      streetName: "Broadway",
      cityName: "New York"
    }

    // I would have expected or I want I should say 
    {
     "state": "NY",
     "firstName": "Fred",
     "lastName": "Smith",
     "streetName": "Broadway",
     "cityName": "New York",
     "PersonalInfo": {
       "EyeColor":"Green",
       "FavoriteColor": "Yellow",
       "height":"SixFeet",
       "Weight":"189"
     }
    }