Ignore fields from Java object dynamically while sending as JSON from Spring MVC

Add the @JsonIgnoreProperties("fieldname") annotation to your POJO.

Or you can use @JsonIgnore before the name of the field you want to ignore while deserializing JSON. Example:

@JsonIgnore @JsonProperty(value = "user_password") public String getUserPassword() { return userPassword; } 

GitHub example

Can I do it dynamically?

Create view class:

public class View { static class Public { } static class ExtendedPublic extends Public { } static class Internal extends ExtendedPublic { } } 

Annotate you model

@Document public class User { @Id @JsonView(View.Public.class) private String id; @JsonView(View.Internal.class) private String email; @JsonView(View.Public.class) private String name; @JsonView(View.Public.class) private Instant createdAt = Instant.now(); // getters/setters } 

Specify the view class in your controller

@RequestMapping("/user/{email}") public class UserController { private final UserRepository userRepository; @Autowired UserController(UserRepository userRepository) { this.userRepository = userRepository; } @RequestMapping(method = RequestMethod.GET) @JsonView(View.Internal.class) public @ResponseBody Optional<User> get(@PathVariable String email) { return userRepository.findByEmail(email); } } 

Data example:

{"id":"5aa2496df863482dc4da2067","name":"test","createdAt":"2018-03-10T09:35:31.050353800Z"} 

UPD: keep in mind that it's not best practice to use entity in response. Better use different DTO for each case and fill them using modelmapper

I know I'm a bit late to the party, but I actually ran into this as well a few months back. All of the available solutions weren't very appealing to me (mixins? ugh!), so I ended up creating a new library to make this process cleaner. It's available here if anyone would like to try it out: https://github.com/monitorjbl/spring-json-view.

The basic usage is pretty simple, you use the JsonView object in your controller methods like so:

import com.monitorjbl.json.JsonView; import static com.monitorjbl.json.Match.match; @RequestMapping(method = RequestMethod.GET, value = "/myObject") @ResponseBody public void getMyObjects() { //get a list of the objects List<MyObject> list = myObjectService.list(); //exclude expensive field JsonView.with(list).onClass(MyObject.class, match().exclude("contains")); } 

You can also use it outside of Spring:

import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.module.SimpleModule; import static com.monitorjbl.json.Match.match; ObjectMapper mapper = new ObjectMapper(); SimpleModule module = new SimpleModule(); module.addSerializer(JsonView.class, new JsonViewSerializer()); mapper.registerModule(module); mapper.writeValueAsString(JsonView.with(list) .onClass(MyObject.class, match() .exclude("contains")) .onClass(MySmallObject.class, match() .exclude("id")); 

We can do this by setting access to JsonProperty.Access.WRITE_ONLY while declaring the property.

@JsonProperty( value = "password", access = JsonProperty.Access.WRITE_ONLY) @SerializedName("password") private String password; 

Yes, you can specify which fields are serialized as JSON response and which to ignore. This is what you need to do to implement Dynamically ignore properties.

1) First, you need to add @JsonFilter from com.fasterxml.jackson.annotation.JsonFilter on your entity class as.

import com.fasterxml.jackson.annotation.JsonFilter; @JsonFilter("SomeBeanFilter") public class SomeBean { private String field1; private String field2; private String field3; // getters/setters } 

2) Then in your controller, you have to add create the MappingJacksonValue object and set filters on it and in the end, you have to return this object.

import java.util.Arrays; import java.util.List; import org.springframework.http.converter.json.MappingJacksonValue; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RestController; import com.fasterxml.jackson.databind.ser.FilterProvider; import com.fasterxml.jackson.databind.ser.impl.SimpleBeanPropertyFilter; import com.fasterxml.jackson.databind.ser.impl.SimpleFilterProvider; @RestController public class FilteringController { // Here i want to ignore all properties except field1,field2. @GetMapping("/ignoreProperties") public MappingJacksonValue retrieveSomeBean() { SomeBean someBean = new SomeBean("value1", "value2", "value3"); SimpleBeanPropertyFilter filter = SimpleBeanPropertyFilter.filterOutAllExcept("field1", "field2"); FilterProvider filters = new SimpleFilterProvider().addFilter("SomeBeanFilter", filter); MappingJacksonValue mapping = new MappingJacksonValue(someBean); mapping.setFilters(filters); return mapping; } } 

This is what you will get in response:

{ field1:"value1", field2:"value2" } 

instead of this:

{ field1:"value1", field2:"value2", field3:"value3" } 

Here you can see it ignores other properties(field3 in this case) in response except for property field1 and field2.

Hope this helps.

Add @JsonInclude(JsonInclude.Include.NON_NULL) (forces Jackson to serialize null values) to the class as well as @JsonIgnore to the password field.

You could of course set @JsonIgnore on createdBy and updatedBy as well if you always want to ignore then and not just in this specific case.

UPDATE

In the event that you do not want to add the annotation to the POJO itself, a great option is Jackson's Mixin Annotations. Check out the documentation

I've solved using only @JsonIgnore like @kryger has suggested. So your getter will become:

@JsonIgnore public String getEncryptedPwd() { return this.encryptedPwd; } 

You can set @JsonIgnore of course on field, setter or getter like described here.

And, if you want to protect encrypted password only on serialization side (e.g. when you need to login your users), add this @JsonProperty annotation to your field:

@JsonProperty(access = Access.WRITE_ONLY) private String encryptedPwd; 

More info here.

If I were you and wanted to do so, I wouldn't use my User entity in Controller layer.Instead I create and use UserDto (Data transfer object) to communicate with business(Service) layer and Controller. You can use Apache BeanUtils(copyProperties method) to copy data from User entity to UserDto.

I have created a JsonUtil which can be used to ignore fields at runtime while giving a response.

Example Usage : First argument should be any POJO class (Student) and ignoreFields is comma seperated fields you want to ignore in response.

 Student st = new Student(); createJsonIgnoreFields(st,"firstname,age"); import java.util.logging.Logger; import org.codehaus.jackson.map.ObjectMapper; import org.codehaus.jackson.map.ObjectWriter; import org.codehaus.jackson.map.ser.FilterProvider; import org.codehaus.jackson.map.ser.impl.SimpleBeanPropertyFilter; import org.codehaus.jackson.map.ser.impl.SimpleFilterProvider; public class JsonUtil { public static String createJsonIgnoreFields(Object object, String ignoreFields) { try { ObjectMapper mapper = new ObjectMapper(); mapper.getSerializationConfig().addMixInAnnotations(Object.class, JsonPropertyFilterMixIn.class); String[] ignoreFieldsArray = ignoreFields.split(","); FilterProvider filters = new SimpleFilterProvider() .addFilter("filter properties by field names", SimpleBeanPropertyFilter.serializeAllExcept(ignoreFieldsArray)); ObjectWriter writer = mapper.writer().withFilters(filters); return writer.writeValueAsString(object); } catch (Exception e) { //handle exception here } return ""; } public static String createJson(Object object) { try { ObjectMapper mapper = new ObjectMapper(); ObjectWriter writer = mapper.writer().withDefaultPrettyPrinter(); return writer.writeValueAsString(object); }catch (Exception e) { //handle exception here } return ""; } } 

Can I do it dynamically?

Yes, you can use a combination of Jackson's PropertyFilter and mixins.

Explanation

Jackson has a PropertyFilter interface to implement a filter to ignore fields dynamically. The problem is that filter has to be defined on the DTO/POJO class using the @JsonFilter annotation.

To avoid adding a @JsonFilter on class we can use ObjectMapper's addMixIn method to "dynamically" add this annotation (and leave our DTO/POJO classes as is).

Code example

Here is my implementation of the idea provided above. We can call toJson() with two arguments: (1) object to be serialized and (2) lambda (Java's Predicate) to be used in PropertyFilter:

public class JsonService { public String toJson(Object object, Predicate<PropertyWriter> filter) { ObjectMapper mapper = new ObjectMapper(); FilterProvider filterProvider = new SimpleFilterProvider() .addFilter("DynamicFilter", new DynamicFilter(filter)); mapper.setFilterProvider(filterProvider); mapper.addMixIn(object.getClass(), DynamicFilterMixin.class); try { return mapper.writeValueAsString(object); } catch (JsonProcessingException e) { throw new MyException(e); } } private static final class DynamicFilter extends SimpleBeanPropertyFilter { private Predicate<PropertyWriter> filter; private DynamicFilter(Predicate<PropertyWriter> filter) { this.filter = filter; } protected boolean include(BeanPropertyWriter writer) { return include((PropertyWriter) writer); } protected boolean include(PropertyWriter writer) { return filter.test(writer); } } @JsonFilter("DynamicFilter") private interface DynamicFilterMixin { } } 

Now we can call toJson and filter fields during a serialization:

1. Filtering by name

new JsonService().toJson(object, w -> !w.getName().equals("fieldNameToBeIgnored")); 

2. Filtering by annotation (on the field)

new JsonService().toJson(object, w -> w.getAnnotation(MyAnnotation.class) == null); 

Unit tests

Here are the unit tests for the class above:

public class JsonServiceTest { private JsonService jsonService = new JsonService(); @Test public void withoutFiltering() { MyObject object = getObject(); String json = jsonService.toJson(object, w -> true); assertEquals("{\"myString\":\"stringValue\",\"myInteger\":10,\"myBoolean\":true}", json); } @Test public void filteredByFieldName() { MyObject object = getObject(); String json = jsonService.toJson(object, w -> !w.getName().equals("myString")); assertEquals("{\"myInteger\":10,\"myBoolean\":true}", json); } @Test public void filteredByAnnotation() { MyObject object = getObject(); String json = jsonService.toJson(object, w -> w.getAnnotation(Deprecated.class) == null); assertEquals("{\"myString\":\"stringValue\",\"myInteger\":10}", json); } private MyObject getObject() { MyObject object = new MyObject(); object.myString = "stringValue"; object.myInteger = 10; object.myBoolean = true; return object; } private static class MyObject { private String myString; private int myInteger; @Deprecated private boolean myBoolean; public String getMyString() { return myString; } public void setMyString(String myString) { this.myString = myString; } public int getMyInteger() { return myInteger; } public void setMyInteger(int myInteger) { this.myInteger = myInteger; } public boolean isMyBoolean() { return myBoolean; } public void setMyBoolean(boolean myBoolean) { this.myBoolean = myBoolean; } } } 

I've found a solution for me with Spring and jackson

First specify the filter name in the entity

@Entity @Table(name = "SECTEUR") @JsonFilter(ModelJsonFilters.SECTEUR_FILTER) public class Secteur implements Serializable { /** Serial UID */ private static final long serialVersionUID = 5697181222899184767L; /** * Unique ID */ @Id @JsonView(View.SecteurWithoutChildrens.class) @Column(name = "id") @GeneratedValue(strategy = GenerationType.IDENTITY) private long id; @JsonView(View.SecteurWithoutChildrens.class) @Column(name = "code", nullable = false, length = 35) private String code; /** * Identifiant du secteur parent */ @JsonView(View.SecteurWithoutChildrens.class) @Column(name = "id_parent") private Long idParent; @OneToMany(fetch = FetchType.LAZY) @JoinColumn(name = "id_parent") private List<Secteur> secteursEnfants = new ArrayList<>(0); } 

Then you can see the constants filters names class with the default FilterProvider used in spring configuration

public class ModelJsonFilters { public final static String SECTEUR_FILTER = "SecteurFilter"; public final static String APPLICATION_FILTER = "ApplicationFilter"; public final static String SERVICE_FILTER = "ServiceFilter"; public final static String UTILISATEUR_FILTER = "UtilisateurFilter"; public static SimpleFilterProvider getDefaultFilters() { SimpleBeanPropertyFilter theFilter = SimpleBeanPropertyFilter.serializeAll(); return new SimpleFilterProvider().setDefaultFilter(theFilter); } } 

Spring configuration :

@EnableWebMvc @Configuration @ComponentScan(basePackages = "fr.sodebo") public class ApiRootConfiguration extends WebMvcConfigurerAdapter { @Autowired private EntityManagerFactory entityManagerFactory; /** * config qui permet d'éviter les "Lazy loading Error" au moment de la * conversion json par jackson pour les retours des services REST<br> * on permet à jackson d'acceder à sessionFactory pour charger ce dont il a * besoin */ @Override public void configureMessageConverters(List<HttpMessageConverter<?>> converters) { super.configureMessageConverters(converters); MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter(); ObjectMapper mapper = new ObjectMapper(); // config d'hibernate pour la conversion json mapper.registerModule(getConfiguredHibernateModule());// // inscrit les filtres json subscribeFiltersInMapper(mapper); // config du comportement de json views mapper.configure(MapperFeature.DEFAULT_VIEW_INCLUSION, false); converter.setObjectMapper(mapper); converters.add(converter); } /** * config d'hibernate pour la conversion json * * @return Hibernate5Module */ private Hibernate5Module getConfiguredHibernateModule() { SessionFactory sessionFactory = entityManagerFactory.unwrap(SessionFactory.class); Hibernate5Module module = new Hibernate5Module(sessionFactory); module.configure(Hibernate5Module.Feature.FORCE_LAZY_LOADING, true); return module; } /** * inscrit les filtres json * * @param mapper */ private void subscribeFiltersInMapper(ObjectMapper mapper) { mapper.setFilterProvider(ModelJsonFilters.getDefaultFilters()); } } 

Endly I can specify a specific filter in restConstoller when i need....

@RequestMapping(value = "/{id}/droits/", method = RequestMethod.GET) public MappingJacksonValue getListDroits(@PathVariable long id) { LOGGER.debug("Get all droits of user with id {}", id); List<Droit> droits = utilisateurService.findDroitsDeUtilisateur(id); MappingJacksonValue value; UtilisateurWithSecteurs utilisateurWithSecteurs = droitsUtilisateur.fillLists(droits).get(id); value = new MappingJacksonValue(utilisateurWithSecteurs); FilterProvider filters = ModelJsonFilters.getDefaultFilters().addFilter(ModelJsonFilters.SECTEUR_FILTER, SimpleBeanPropertyFilter.serializeAllExcept("secteursEnfants")).addFilter(ModelJsonFilters.APPLICATION_FILTER, SimpleBeanPropertyFilter.serializeAllExcept("services")); value.setFilters(filters); return value; } 

Place @JsonIgnore on the field or its getter, or create a custom dto

@JsonIgnore private String encryptedPwd; 

or as mentioned above by ceekay annotate it with @JsonProperty where access attribute is set to write only

@JsonProperty( value = "password", access = JsonProperty.Access.WRITE_ONLY) private String encryptedPwd; 

Hi I have achieved dynamic filtering by using Gson library like in the below:

JsonObject jsonObj = new Gson().fromJson(mapper.writeValueAsString(sampleObject), JsonObject.class); jsonObj.remove("someProperty"); String data = new Gson().toJson(jsonObj); 

Would not creating a UserJsonResponse class and populating with the wanted fields be a cleaner solution?

Returning directly a JSON seems a great solution when you want to give all the model back. Otherwise it just gets messy.

In the future, for example you might want to have a JSON field that does not match any Model field and then you're in a bigger trouble.

This is a clean utility tool for the above answer :

@GetMapping(value = "/my-url") public @ResponseBody MappingJacksonValue getMyBean() { List<MyBean> myBeans = Service.findAll(); MappingJacksonValue mappingValue = MappingFilterUtils.applyFilter(myBeans, MappingFilterUtils.JsonFilterMode.EXCLUDE_FIELD_MODE, "MyFilterName", "myBiggerObject.mySmallerObject.mySmallestObject"); return mappingValue; } //AND THE UTILITY CLASS public class MappingFilterUtils { public enum JsonFilterMode { INCLUDE_FIELD_MODE, EXCLUDE_FIELD_MODE } public static MappingJacksonValue applyFilter(Object object, final JsonFilterMode mode, final String filterName, final String... fields) { if (fields == null || fields.length == 0) { throw new IllegalArgumentException("You should pass at least one field"); } return applyFilter(object, mode, filterName, new HashSet<>(Arrays.asList(fields))); } public static MappingJacksonValue applyFilter(Object object, final JsonFilterMode mode, final String filterName, final Set<String> fields) { if (fields == null || fields.isEmpty()) { throw new IllegalArgumentException("You should pass at least one field"); } SimpleBeanPropertyFilter filter = null; switch (mode) { case EXCLUDE_FIELD_MODE: filter = SimpleBeanPropertyFilter.serializeAllExcept(fields); break; case INCLUDE_FIELD_MODE: filter = SimpleBeanPropertyFilter.filterOutAllExcept(fields); break; } FilterProvider filters = new SimpleFilterProvider().addFilter(filterName, filter); MappingJacksonValue mapping = new MappingJacksonValue(object); mapping.setFilters(filters); return mapping; } } 

To acheive dynamic filtering follow the link - https://iamvickyav.medium.com/spring-boot-dynamically-ignore-fields-while-converting-java-object-to-json-e8d642088f55

1. Add the @JsonFilter("Filter name") annotation to the model class.

2. Inside the controller function add the code:-

   SimpleBeanPropertyFilter simpleBeanPropertyFilter = SimpleBeanPropertyFilter.serializeAllExcept("id", "dob"); FilterProvider filterProvider = new SimpleFilterProvider() .addFilter("Filter name", simpleBeanPropertyFilter); List<User> userList = userService.getAllUsers(); MappingJacksonValue mappingJacksonValue = new MappingJacksonValue(userList); mappingJacksonValue.setFilters(filterProvider); return mappingJacksonValue; 

3. make sure the return type is MappingJacksonValue.

Simply create new dto class without field password.

class UserDto { // ... your field without password field } 

convert your User.java into UserDto.java on response.