I have model class like this, for hibernate
#Entity
#Table(name = "user", catalog = "userdb")
#JsonIgnoreProperties(ignoreUnknown = true)
public class User implements java.io.Serializable {
private Integer userId;
private String userName;
private String emailId;
private String encryptedPwd;
private String createdBy;
private String updatedBy;
#Id
#GeneratedValue(strategy = IDENTITY)
#Column(name = "UserId", unique = true, nullable = false)
public Integer getUserId() {
return this.userId;
}
public void setUserId(Integer userId) {
this.userId = userId;
}
#Column(name = "UserName", length = 100)
public String getUserName() {
return this.userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
#Column(name = "EmailId", nullable = false, length = 45)
public String getEmailId() {
return this.emailId;
}
public void setEmailId(String emailId) {
this.emailId = emailId;
}
#Column(name = "EncryptedPwd", length = 100)
public String getEncryptedPwd() {
return this.encryptedPwd;
}
public void setEncryptedPwd(String encryptedPwd) {
this.encryptedPwd = encryptedPwd;
}
public void setCreatedBy(String createdBy) {
this.createdBy = createdBy;
}
#Column(name = "UpdatedBy", length = 100)
public String getUpdatedBy() {
return this.updatedBy;
}
public void setUpdatedBy(String updatedBy) {
this.updatedBy = updatedBy;
}
}
In Spring MVC controller, using DAO, I am able to get the object. and returning as JSON Object.
#Controller
public class UserController {
#Autowired
private UserService userService;
#RequestMapping(value = "/getUser/{userId}", method = RequestMethod.GET)
#ResponseBody
public User getUser(#PathVariable Integer userId) throws Exception {
User user = userService.get(userId);
user.setCreatedBy(null);
user.setUpdatedBy(null);
return user;
}
}
View part is done using AngularJS, so it will get JSON like this
{
"userId" :2,
"userName" : "john",
"emailId" : "john#gmail.com",
"encryptedPwd" : "Co7Fwd1fXYk=",
"createdBy" : null,
"updatedBy" : null
}
If I don't want to set encrypted Password, I will set that field also as null.
But I don't want like this, I dont want to send all fields to client side. If I dont want password, updatedby, createdby fields to send, My result JSON should be like
{
"userId" :2,
"userName" : "john",
"emailId" : "john#gmail.com"
}
The list of fields which I don't want to send to client coming from other database table. So it will change based on the user who is logged in. How can I do that?
I hope You got my question.
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"));
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.
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;
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 "";
}
}
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;
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:
Filtering by name
new JsonService().toJson(object, w -> !w.getName().equals("fieldNameToBeIgnored"));
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;
}
}
}
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
Add the #JsonFilter("Filter name") annotation to the model class.
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;
make sure the return type is MappingJacksonValue.
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);
In your entity class add #JsonInclude(JsonInclude.Include.NON_NULL) annotation to resolve the problem
it will look like
#Entity
#JsonInclude(JsonInclude.Include.NON_NULL)
Related
I have a service which is returning a List in JSON format.
Please find below code :
public List<SampleList> getValues() {
List<SampleList> sample = null;
sample= DAOFactory.sampleDAO.findByCriteria().add(Restrictions.isNull("endDate")).list();
return sample;
}
Class SampleList.java
public class SampleList {
private Integer categoryId;
private String categoryName;
//getter setter
}
Now my service is returning the JSON like below
{
categoryId : 1,
categoryName : "Test"
}
But I need anotherlist to be encapsulated here. Iw ant below output
{
categoryId : 1,
categoryName : "Test"
subCategory:
{
name: ""
}
}
For subCategory attribute I have another class similar to SampleList.java. I can get the sub categories corresponding to each category. Can anyone help me out to get expected response?
I dont want to touch my SampleList class.
You have to extend your class SampleList
Class SampleList.java
public class SampleList {
private Integer categoryId;
private String categoryName;
private SubCategory subCategory;
//getter setter
And before you return your list of course you have to set the correct subCategory in your SampleList item.
If you don't want to spoil your SampleList class of course you could add a layer of DTO objects and map between them or manipulate the response directly e.g. with ResponseBodyAdvice
Approach : 1
public class SampleList
{
private Integer categoryId;
private String categoryName;
// Getter and Setter
}
public class SampleList2
{
private String name;
// Getter and Setter
}
// Logic to get the JSON value without mapping two different classes
private void getJsonValue() throws JsonProcessingException, JSONException
{
SampleList sampleList = new SampleList();
sampleList.setCategoryId(1);
sampleList.setCategoryName("cat 1");
String sampleListJson = new ObjectMapper().writeValueAsString(sampleList);
SampleList2 sampleList2 = new SampleList2();
sampleList2.setName("Sub category");
String valueOfSample2 = new ObjectMapper().writeValueAsString(sampleList2);
JSONObject sampleListJsonObj = new JSONObject(sampleListJson); // for class SampleList
JSONObject sampleList2JsonObj = new JSONObject(valueOfSample2); // for class SampleList2
sampleListJsonObj.put("subCategory", sampleList2JsonObj);
System.out.println(sampleListJsonObj.toString());
}
Approach : 2
public class SampleList
{
private Integer categoryId;
private String categoryName;
private SampleList2 subCategory;
// Getter and Setter
}
public class SampleList2
{
private String name;
// Getter and Setter
}
// Logic to get with mapping two classes as mentioned above
private static void getJsonValue() throws JsonProcessingException
{
SampleList sampleList = new SampleList();
sampleList.setCategoryId(1);
sampleList.setCategoryName("cat 1");
SampleList2 sampleList2 = new SampleList2();
sampleList2.setName("Sub category");
sampleList.setSubCategory(sampleList2);
String jsonString = new ObjectMapper().writeValueAsString(sampleList);
System.out.println(jsonString.toString());
}
Please let me know if you have any questions on the same.
Thank you.
I would like to deserialize JSON of this structure:
{
"employee_pricing_type":"COMPUTE_BY_OWN_RATE",
"employee_rate":10,
"customer_pricing_type":"COMPUTE_BY_OWN_RATE",
"customer_rate":200
}
I have such POJO to create price setting from a HTTP request:
public class ObjectPricingSetting {
#JsonProperty("pricing_type") // describes output
private final ObjectPricingType pricingType;
#JsonProperty("own_rate") // describes output
private final BigDecimal ownRate;
public ObjectPricingSetting(final ObjectPricingType pricingType, final BigDecimal ownRate) {
AssertUtils.notNull(pricingType, "pricingType");
this.pricingType = pricingType;
if (ownRate != null) {
AssertUtils.isGtZero(ownRate, "ownRate");
this.ownRate = ownRate;
} else {
this.ownRate = null;
}
}
public ObjectPricingType getPricingType() {
return pricingType;
}
public BigDecimal getOwnRate() {
return ownRate;
}
}
this is DTO:
#JsonInclude(JsonInclude.Include.NON_NULL)
public class ObjectPricingCommand extends BaseDto<ObjectId> {
#JsonProperty(value = "employee_pricing_setting")
private ObjectPricingSetting employeePricingSetting;
#JsonProperty(value = "customer_pricing_setting")
private ObjectPricingSetting customerPricingSetting;
}
I would like to create these two instances of ObjectPricingSetting with #JsonCreator.
Q: How should I anotate #JsonProperty parameter in ObjectPricingSetting constructor to recognize what JSON value should use to create these two instances?
You can use #JsonUnwrapped with a prefix in your parent class:
#JsonInclude(JsonInclude.Include.NON_NULL)
public class ObjectPricingCommand extends BaseDto<ObjectId> {
#JsonUnwrapped(prefix = "employee_")
private ObjectPricingSetting employeePricingSetting;
#JsonUnwrapped(prefix = "customer_")
private ObjectPricingSetting customerPricingSetting;
}
Then you can use the normal #JsonCreator/#JsonProperty in your nested DTO, without the prefix:
public class ObjectPricingSetting {
#JsonCreator
public ObjectPricingSetting(
#JsonProperty("pricing_type") final ObjectPricingType pricingType,
#JsonProperty("rate") final BigDecimal ownRate) {
...
I have in my controller:
#RestController
public class OneTwoController {
private OnTwoService _service;
//... more code
#PostMapping("/api/one-two")
#CrossOrigin
public ResponseEntity<ServiceResponse> save(#RequestBody OneTwo model) {
return ResponseEntity.ok().body( _service.Save(model));
}
In my entity:
#Entity(name = "OneTwo")
#Where (clause = "deleted='false'")
public class OneTwo{
#EmbeddedId
private OneTwoKey_id;
public OneTwo(OneTwoKey id) {
this._id = id;
}
#JsonProperty("oneTwo")
public void setId(OneTwoKey value) {
this._id = value;
}
The OneTwoKey class:
public class OneTwoKey implements Serializable {
#Column(name = "OneID")
private int _oneID;
#Column(name = "TwoID")
private int _twoID;
public OneTwoKey(int oneID, int twoID) {
this._oneID = oneID;
this._twoID = twoID;
}
}
The json that I send to the Rest API:
{
"oneTwo": {
"oneID": 83,
"twoID": 69
},
"deleted": true
}
The issue is that both ids arrive null, so the service can't do the insert on the DB.
How can I deal with those cases when the ids are more than one?
Try adding setters in the OneTwoKey class to make it easier for the JSON deserializer:
#JsonProperty("oneID")
public void setOneID(int oneID) {
this._oneID = oneID;
}
#JsonProperty("twoID")
public void setTwoID(int twoID) {
this._twoID = twoID;
}
Another solution is to create a DTO, use it to receive the data in the controller and then convert it to your entity:
public class OneTwoDTO {
private Map<String, Int> oneTwo;
private boolean deleted;
// setters & getters
}
Simply what you can do is instead of using
public ResponseEntity<ServiceResponse> save(#RequestBody OneTwo model) {
you can use
public ResponseEntity<ServiceResponse> save(#RequestBody String model) {
Now convert the String to json and get all the key value pairs, it would be easier if you have dynamic number of variables and you want to capture them all.
or you can use tools like jsonschema2pojo whick take a json schema and generate a pojo. In the json schema if you set
"additionalProperties": true
you can capture all the values.
Could you make sure the problem is not because of case sensitivity?
Lower case the column names. Also could you use public access on those variables as well? These are my initial guesses as to why the payload is not being binded correctly.
public class OneTwoKey implements Serializable {
#Column(name = "oneID")
public int _oneID;
#Column(name = "twoID")
public int _twoID;
I have a Class So as shown below:
#Entity
#Table(name = "so", schema = "public")
public class So implements java.io.Serializable , IBusiness {
private int idSo;
private Set<PartOrder> partOrders = new HashSet<PartOrder>();
public So() {
}
#Id
#SequenceGenerator(name = "seqGenerator", sequenceName = "so_seq", allocationSize=1, initialValue=1)
#GeneratedValue(generator="seqGenerator", strategy=GenerationType.SEQUENCE)
#Column(name = "id_so", unique = true, nullable = false)
public int getIdSo() {
return this.idSo;
}
public void setIdSo(int idSo) {
this.idSo = idSo;
}
#OneToMany(fetch = FetchType.LAZY, mappedBy = "so")
public Set<PartOrder> getPartOrders() {
return this.partOrders;
}
public void setPartOrders(Set<PartOrder> partOrders) {
this.partOrders = partOrders;
}
}
I have a method that returns a Json with the SO. But i don not want the partOrders attribute to be included on the response json. I was using #JsonIgnore on the attribute but now, i have another method that receives an SO object and i need to get the partOders.
The question is: Is there any way to specify when to ignore the attribute (in specific method) ?
You can achieve this by using Json Filter with a FilterProvider
you use #JsonFilter annotation to assign a filter name to your POJO.
before serialization, you attach an instance of SimpleBeanPropertyFilter to the filter name. the class has two factory methods for filters that work based on propertry names.
Here is an example of the annotation declaration:
#JsonFilter("filter properties by name")
public class So {
public String alwaysWrite = "alwaysWriteValue";
public String somtimeIgnore = "somtimeIgnoreValue";
}
here is a method that assignes a filter that will ignore somtimeIgnore property
public void dontWriteSomtimes(So so) {
ObjectMapper mapper = new ObjectMapper();
FilterProvider filters = new SimpleFilterProvider()
.addFilter("filter properties by name", SimpleBeanPropertyFilter.serializeAllExcept("somtimeIgnore"));
ObjectWriter writer = mapper.writer(filters);
try {
System.out.println(writer.writeValueAsString(so));
} catch (Exception e) {
e.printStackTrace();
}
}
output:
{"alwaysWrite":"alwaysWriteValue"}
here is a method that will write everything: just assign a non-existent or empty property:
public void writeEveryting(So so) {
ObjectMapper mapper = new ObjectMapper();
FilterProvider filters = new SimpleFilterProvider()
.addFilter("filter properties by name", SimpleBeanPropertyFilter.serializeAllExcept(""));
ObjectWriter writer = mapper.writer(filters);
try {
System.out.println(writer.writeValueAsString(so));
} catch (Exception e) {
e.printStackTrace();
}
}
output:
{"alwaysWrite":"alwaysWriteValue","somtimeIgnore":"somtimeIgnoreValue"}
you put jSON ignore annotation for your class. i think it will overcome your requirement. you can leave unwanted properties here.
#JsonIgnoreProperties(ignoreUnknown = true)
class ClassName{
}
I have these two classes:
#JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id",scope = Rol.class)
public class Rol extends MyEntity implements Serializable {
private Integer id;
private String rolName;
public Rol(Integer id, String rolName) {
this.id = id;
this.rolName = rolName;
}
...
}
#JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id",scope = User.class)
public class User extends MyEntity implements Serializable {
private Integer id;
private String name;
private List<Rol> rolList;
public User(Integer id, String name, List<Rol> rolList) {
this.id = id;
this.name = name;
this.rolList = rolList;
}
...
}
and I try to serialize and deserialize the user object as following
Rol rol1 = new Rol(1, "MyRol");
Rol rol2 = new Rol(1, "MyRol");
List<Rol> rolList = new ArrayList();
rolList.add(rol1);
rolList.add(rol2);
user = new User(1, "MyUser", rolList);
ObjectMapper mapper = new ObjectMapper();
String jsonString = mapper.writeValueAsString(user);
User userJson = mappe.readValue(jsonString, User.class);
and the JsonMappingException: Already had POJO for id is produced. Why?
When I review the json result of the serialization I see that the result is
{"id": 1,"name": "MyName","rolList": [{"id": 1,"rolName": "MyRol"},{"id": 1,"rolName": "MyRol"}]}
when the result should be
{"id": 1,"name": "MyName","rolList": [{"id": 1,"rolName": "MyRol"},1]}
because rol1 and rol2 are different instances of the same POJO identifier with id 1.
How can I avoid the JsonMappingException? In my project I have some different instances of the same POJO. I can guarantee that if the id's are equal -> objects are equal.
Excuse me for my bad English.
For anyone returning to this question, it looks like there's option to do this with a custom ObjectIdResolver in Jackson. You can specify this on the #JsonIdentityInfo annotation, e.g. :
#JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "name",
resolver = CustomObjectIdResolver.class)
Then perhaps wrap the normal SimpleObjectIdResolver class to get going and customise bindItem().
In my case I wanted to avoid overlapping objectIds, so cleared down the references when I started a new Something:
public class CustomObjectIdResolver implements ObjectIdResolver {
private ObjectIdResolver objectIdResolver;
public CustomObjectIdResolver() {
clearReferences();
}
#Override
public void bindItem(IdKey id, Object pojo) {
// Time to drop the references?
if (pojo instanceof Something)
clearReferences();
objectIdResolver.bindItem(id, pojo);
}
#Override
public Object resolveId(IdKey id) {
return objectIdResolver.resolveId(id);
}
#Override
public boolean canUseFor(ObjectIdResolver resolverType) {
return resolverType.getClass() == getClass();
}
#Override
public ObjectIdResolver newForDeserialization(Object context) {
return new CustomObjectIdResolver();
}
private void clearReferences() {
objectIdResolver = new SimpleObjectIdResolver();
}
}
Jackson expects in this case different id for different class instances. There has been a previous discussion at github here. Overriding hashCode and equals will not help. Object references must match for equal id.
Options
Reuse Rol instances instead of making new ones with equal fields. As a bonus you will also save memory.
Modify the application logic so that it doesn't depend on #JsonIdentityInfo