RESTful Java Servlet: Serializing to/from JSON with Jackson

org.codehaus.jackson.map.JsonMappingException: No serializer found for class DataClass and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS)

import java.util.ArrayList;
import java.util.List;
 
import org.codehaus.jackson.annotate.JsonAutoDetect;
import org.codehaus.jackson.annotate.JsonIgnoreProperties;
import org.codehaus.jackson.annotate.JsonProperty;
 
@JsonAutoDetect   // use this annotation if you don't have getters and setters for each JsonProperty
//@JsonIgnoreProperties(ignoreUnknown = true)    // use this if there isn't an exact correlation between JSON and class properties
public class DataClass {
 
  //@JsonProperty("theid") // use this if the property in JSON has a different identifier than your class
  @JsonProperty
  private int id = 1;
 
  @JsonProperty
  private String name = "Test Class";
 
  @JsonProperty
  private List<String> messages = new ArrayList<String>() {
    {
      add("msg 1");
      add("msg 2");
      add("msg 3");
    }
  };
}

import java.util.ArrayList;
import java.util.List;
 
public class DataClass {
 
  private int id = 1;
 
  private String name = "Test Class";
 
  private List<String> messages = new ArrayList<String>() {
    {
      add("msg 1");
      add("msg 2");
      add("msg 3");
    }
  };
 
  public String toString() {
    return "User [id=" + id + ", name=" + name + ", " + "messages=" + messages + "]";
  }
  public int getId() {
    return id;
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getName() {
    return name;
  }
  public void setName(String name) {
    this.name = name;
  }
  public List<String> getMessages() {
    return messages;
  }
  public void setMessages(List<String> messages) {
    this.messages = messages;
  }
}

...
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    PrintWriter out = response.getWriter();
 
    DataClass mydata = new DataClass();
    ObjectMapper mapper = new ObjectMapper();
 
    try {
      // display to console
      out.println(mapper.writeValueAsString(mydata));
    } catch (JsonGenerationException e) {
      e.printStackTrace();
    } catch (JsonMappingException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    }
    out.close();
  }
 
  protected void doPost(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    PrintWriter out = response.getWriter();
 
    ObjectMapper mapper = new ObjectMapper();
 
    try {
      // read from file, convert it to user class
      DataClass user = mapper.readValue(request.getReader(), DataClass.class);
      // display to console
      out.println(user);
    } catch (JsonGenerationException e) {
      e.printStackTrace();
    } catch (JsonMappingException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    }
    out.close();
  }
...