Jacskon ignores @JsonIgnore annotation in nested class of hierarchy

Question

I havea spring based java app that I am currently developing Long story short - here is the code I use to retrieve an object from the db, do some calculations on the same and render it

@RequestMapping(value = { "/mapping" }, method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
public Object getMasterAppMappingById(
        @PathVariable(value = "masterAppId") Integer masterAppId) {  

    RestBaseVO masterAppMappingRestBaseVO = new RestBaseVO();

    MasterAppMappingTreeDetailsVO masterAppMappingTreeDetailsById = applicationDeviceServices.getMasterAppMappingTreeDetails(masterAppId, true);

    return masterAppMappingTreeDetailsById;
}

The problem I have is, the code is fine right up until jackson kicks in and converts it. At the return statement is my bottleneck

The method getMasterAppMappingTreeDetails works perfectly and performs well

The json that is rendered by jackson is shown at the following url on pastebin http://pastebin.com/erRDtweZ

As you can see - it is fairly big

The classes being serialized are as follows

public class MasterAppMappingTreeDetailsVO {

@JsonProperty("id")
private Integer id;

@JsonProperty("mappingId")
private Integer mappingId;

@JsonProperty("parentMappingId")
private Integer parentMappingId;



 @JsonProperty("isQuestion")
    private boolean isQuestion;

    @JsonProperty("isAnswer")
    private boolean isAnswer;

    @JsonProperty("isApplication")
    private boolean isApplication;

    @JsonProperty("displayLabel")
    private String displayLabel;

    @JsonProperty("additionalText1")
    private String additionalText1;

    @JsonProperty("imageUrl")
    private String imageUrl;

    @JsonProperty("imageDateUpdated")
    private Long imageDateUpdated;

    @JsonProperty("appId")
    private Integer appId;

    @JsonProperty("appName")
    private String appName;

    @JsonProperty("children")
    private List<MasterAppMappingTreeDetailsVO> children;

    @JsonProperty("menuStyle")
    private MenuStyleVO menuStyle;

}


    @Entity
@Table(name = "menu_style")
@JsonIgnoreProperties({"hibernateLazyInitializer", "handler"})
public class MenuStyleVO extends BaseDAOVO implements Serializable{

    /**
     * 
     */
    private static final long serialVersionUID = 3697798179195096156L;

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id", unique = true, nullable = false)
    private Integer id;

    @Column(name = "menuStyleName", unique = false, nullable = false, length = 200)
    private String menuStyleName;

    @Column(name = "menuTemplate", unique = false, nullable = false, length = 200)
    private String menuTemplate;

    @OneToOne(fetch = FetchType.EAGER)
    @Cascade({ CascadeType.SAVE_UPDATE })
    @JoinColumn(name="logo_id")
    @JsonProperty("logo")
    private ApplicationImageVO logo;

    @Column(name = "logoAlignment", unique = false, nullable = true, length = 20)
    private String logoAlignment;

    @Column(name = "backArrowColor", unique = false, nullable = true, length = 7)
    private String backArrowColor;    

    @OneToOne(fetch = FetchType.EAGER)
    @Cascade({ CascadeType.SAVE_UPDATE })
    @JoinColumn(name="backArrowIcon_id")
    @JsonProperty("backArrowIcon")
    private ApplicationImageVO backArrowIcon;

    @Column(name = "questionLabelTextColor", unique = false, nullable = true, length = 7)
    private String questionLabelTextColor;  

    @Column(name = "headerBackgroundColor", unique = false, nullable = true, length = 7)
    private String headerBackgroundColor;      

    @Column(name = "headerBackgroundOpacity", unique = false, nullable = true)
    private Integer headerBackgroundOpacity; 

    @Column(name = "mainBackgroundColor", unique = false, nullable = true, length = 7)
    private String mainBackgroundColor;      

    @Column(name = "mainBackgroundOpacity", unique = false, nullable = true)
    private Integer mainBackgroundOpacity; 

    @OneToOne(fetch = FetchType.EAGER)
    @Cascade({ CascadeType.SAVE_UPDATE })
    @JoinColumn(name="backgroundImageLandscape_id")
    @JsonProperty("backgroundImageLandscape")
    private ApplicationImageVO backgroundImageLandscape;

    @OneToOne(fetch = FetchType.EAGER)
    @Cascade({ CascadeType.SAVE_UPDATE })
    @JoinColumn(name="backgroundImagePortrait_id")
    @JsonProperty("backgroundImagePortrait")
    private ApplicationImageVO backgroundImagePortrait;

    @Column(name = "containerColor", unique = false, nullable = true, length = 7)
    private String containerColor;      

    @Column(name = "containerOpacity", unique = false, nullable = true)
    private Integer containerOpacity; 

    @Column(name = "containerLineDividerColor", unique = false, nullable = true, length = 7)
    private String containerLineDividerColor;      

    @Column(name = "containerLineDividerOpacity", unique = false, nullable = true)
    private Integer containerLineDividerOpacity; 

    @Column(name = "optionIconSize", unique = false, nullable = true)
    private Integer optionIconSize; 

    @Column(name = "optionLabelTextColor", unique = false, nullable = true, length = 7)
    private String optionLabelTextColor;     

    @Column(name = "optionTaglinePosition", unique = false, nullable = true, length = 20)
    private String optionTaglinePosition;   

    @Column(name = "optionTaglineTextColor", unique = false, nullable = true, length = 7)
    private String optionTaglineTextColor; 

    @Column(name = "optionSelectionArrowColor", unique = false, nullable = true, length = 7)
    private String optionSelectionArrowColor;

    @OneToOne(fetch = FetchType.EAGER)
    @Cascade({ CascadeType.SAVE_UPDATE })
    @JoinColumn(name="optionSelectionArrowIcon_id")
    @JsonProperty("optionSelectionArrowIcon")
    private ApplicationImageVO optionSelectionArrowIcon;

}

Can anyone offer any advise on how to improve the performance of this json call or how to improve jackson performance in general for my application?

Answer 1

Problem with Jackson
If you are serializing your entity classes using Jackson API, then putting @JsonIgnore annotation may suffice one case but not all.
If you have some lazy loaded properties, then those will be loaded once Jackson serializes the objects or you would have to load them eagerly, which would definitely have adverse impact on the performance.
If you have Relations between your classes(one-many;many-many etc), then Jackson will load all dependent entities as well when serializing object and you may also get into a circular dependency issue i.e. parent loading child and child loading parent.
Of course, there is a way to overcome that using Jackson API, but in long term, it will become a bottleneck.

Solution
The best way according to me is to create model class for what you want to return and load and return that class before returning from the controller.

This has some pros and cons.

Cons:
1. Of course there would be extra classes and extra code to be maintained.

Pros:
1. Model classes would be separate and there would not be any dependency on your entity classes.
2. Any change in any of the classes will not effect the other class.
3. Properties which are not needed to be rendered can be avoided.
4. You can easily modify your entity class and until your model class is changed there would not be a change in the view.

Hope this helps!!