In the REST endpoint I'm building in Spring Boot, I'm trying to pass my vehicleDTO to my controller. But before it reaches my controller, there is an error.
InvalidDefinitionException: Cannot construct instance of
com.vehicle.datatransferobject.VehicleDTO (no Creators, like default
construct, exist): cannot deserialize from Object value (no delegate-
or property-based Creator)
vehicleDTO
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.myvehicle.EngineType;
#JsonInclude(JsonInclude.Include.NON_NULL)
public class VehicleDTO {
#JsonIgnore
private Long id;
#NotNull(message = "vehiclenumber can not be null!")
private String vehiclenumber;
#Min(2)
#NotNull(message = "Seat count can not be less than 2!")
private Integer vehicleseatcount;
#NotNull(message = "Engine Type can not be null!")
private EngineType enginetype;
#Max(5)
private Integer vehiclerating;
private VehicleDTO(Long id, String vehiclenumber, Integer vehicleseatcount, EngineType enginetype,Integer vehiclerating){
this.vehiclenumber=vehiclenumber;
this.vehicleseatcount=vehicleseatcount;
this.enginetype=enginetype;
this.vehiclerating=vehiclerating;
this.id=id;
}
public static VehicleDTOBuilder newBuilder()
{
return new VehicleDTOBuilder();
}
#JsonProperty
public Long getId() {
return id;
}
public String getvehiclenumber() {
return vehiclenumber;
}
public Integer getvehicleseatcount() {
return vehicleseatcount;
}
public EngineType getEnginetype() {
return enginetype;
}
public Integer getvehiclerating() {
return vehiclerating;
}
public static class VehicleDTOBuilder{
private Long id;
private String vehiclenumber;
private Integer vehicleseatcount;
private EngineType enginetype;
private Integer vehiclerating;
public VehicleDTOBuilder setId(Long id) {
this.id = id;
return this;
}
public VehicleDTOBuilder setvehiclenumber(String vehiclenumber) {
this.vehiclenumber = vehiclenumber;
return this;
}
public VehicleDTOBuilder setvehicleseatcount(Integer vehicleseatcount) {
this.vehicleseatcount = vehicleseatcount;
return this;
}
public VehicleDTOBuilder setEnginetype(EngineType enginetype) {
this.enginetype = enginetype;
return this;
}
public VehicleDTOBuilder setvehiclerating(Integer vehiclerating) {
this.vehiclerating = vehiclerating;
return this;
}
public VehicleDTO createVehicleDTO()
{
return new VehicleDTO(id, vehiclenumber, vehicleseatcount, enginetype,vehiclerating);
}
}
}
My DTO has an Enum type called EngineType
public enum EngineType {
ELECTRIC, DIESEL
}
My controller looks like this
#PostMapping
#ResponseStatus(HttpStatus.CREATED)
public VehicleDTO addvehicle(#Valid #RequestBody VehicleDTO vehicleDTO)
{
VehicleDO vehicleDO = Mapper.VehicleDO(vehicleDTO);
return Mapper.makeVehicleDTO(Service.addvehicle(vehicleDO));
}
This exception :
InvalidDefinitionException: Cannot construct instance of
com.vehicle.datatransferobject.VehicleDTO (no Creators, like default
construct, exist): cannot deserialize from Object value (no delegate-
or property-based Creator)
means that Jackson didn't find a way to instantiate VehicleDTO that is the default constructor (no arg constructor) or a JsonCreator.
As you use a builder pattern you will configure the VehicleDTO class to make Jackson to instantiate VehicleDTO with the VehicleDTOBuilder such as :
#JsonDeserialize(builder = VehicleDTO.VehicleDTOBuilder.class)
public class VehicleDTO {
...
}
And annotate your builder with JsonPOJOBuilder as :
#JsonPOJOBuilder(buildMethodName = "createVehicleDTO", withPrefix = "set")
public static class VehicleDTOBuilder{
...
}
According to the javadoc, JsonPOJOBuilder is :
used to configure details of a Builder class: instances of which are
used as Builders for deserialized POJO values, instead of POJOs being
instantiated using constructors or factory methods. Note that this
annotation is NOT used to define what is the Builder class for a POJO:
rather, this is determined by JsonDeserialize.builder() property of
JsonDeserialize.
I faced this error when I used Lombok's #Builder and #Data annotations together on a POJO class that is used for connecting to an API (either for consuming or for providing response)
I removed the #Builder annotation and then it is working fine
In my case:
InvalidDefinitionException: Cannot construct instance of com.vehicle.datatransferobject.VehicleDTO (no Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
for the above exception, I just write Default Constructor which instantiates class and solved the problem.
Default Constructor:
public VehicleDTO() {
super();
// TODO Auto-generated constructor stub
}
If you are using Lombok - the best thing is to add these annotations to your DTO:
#AllArgsConstructor
#RequiredArgsConstructor
#Data
#Builder (optional)
In addition to davidxxx`s answer. I used Lombok. And in my case it looked like this:
#Data
#JsonDeserialize(builder = SomeClass.SomeClassBuilder.class)
#Builder(builderClassName = "SomeClassBuilder")
public class SomeClass {
// ...
#JsonPOJOBuilder(withPrefix = "")
public static class SomeClassBuilder {
}
}
Related
I have problem while casting an unknown enum to a default enum in spring boot while using mongo repository.
This is the enum.
public enum EventType implements Serializable
{
WORKDONE("WORKDONE"),
ODRCOM("ODRCOM"),
EXECUTED("EXECUTED"),
REBOOK("REBOOK"),
MANUAL("MANUAL"),
UNKNOWN("UNKNOWN");
private String value;
EventType(final String type) {
this.value = type;
}
#Override
public String toString() {
return value;
}
}
And here is my model class
#JsonInclude(JsonInclude.Include.NON_NULL)
public class Event {
//other properties
#JsonProperty("eventType")
private EventType eventType;
#JsonIgnore
private Map<String, Object> additionalProperties = new HashMap<String, Object>();
#JsonProperty("eventType")
public EventType getEventType() {
return eventType;
}
#JsonProperty("eventType")
public void setEventType(String eventType) {
this.eventType = Optional.ofNullable(EventType.valueOf(eventType)).orElse(EventType.UNKNOWN);
}
//other getters and setters
}
Here is the mongo repository
public interface EventRepository extends MongoRepository<Event, String> {
}
The document stored in the db is of the following stucture
{
...
"eventType" : "REBOOK1",
...
}
Please note that the REBOOK1 is not a valid enum. But the setter should be able to able to cast anything else to type UNKNOWN.
However it gives this exception everytime
No enum constant dk.nuuday.ossieventprocessor.app.model.EventType.REBOOK1
I have tried with adding a custom converter as a configuration but no luck
Any help is greatly appreciated
I have simple class and field id is annotated with custom deserializer.
public class TestRequest implements Serializable {
#NotNull
#Pattern(regexp = "^[a-zA-Z0-9=+]*$")
#JsonDeserialize(using = StringDeserializer.class)
#JsonProperty
private String id;
//getter
//setter
}
and the custom deserializer class :
public class StringDeserializer extends JsonDeserializer<String> {
#Override
public String deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) {
Iterator<String> iterator = jsonParser.readValuesAs(String.class);
String id = iterator.next();
return id + "0000";
}
}
When i test with with Jersey REST test, the deserilizer is called and works as expected. But with websphere it does not called. Any idea why its not called.
I am using jaxrs 1.1
You may need to add the #Provider annotation to your StringDeserializer class, otherwise the JAX-RS runtime will not recognize the class as a provdier.
Even though your class extends JsonDeserializer<String>, which itself is probably annotated with #Provider, the JAX-RS runtime will not scan libraries for annotations, as doing negatively impacts performance.
I made it working in Websphere by moving the annotation #JsonDeserialize(using = StringDeserializer.class) to setter method of the class
public class TestRequest implements Serializable {
#NotNull
#Pattern(regexp = "^[a-zA-Z0-9=+]*$")
#JsonProperty
private String id;
#JsonDeserialize(using = StringDeserializer.class)
public setId(String id){
this.id=id;
}
//getter
//setter
}
I am still somewhat of a novice with Spring Boot and Spring Data Rest and hope someone out there with experience in Accessing by Property. Since I cannot change a database which stores types for Letters in an unnormalized fashion (delimited string in a varchar), I thought that I could leverage some logic in properties to overcome this. However I notice that when using property access, some of my getters are never called.
My Model code:
package ...
import ...
#Entity
#Table(name="letters", catalog="clovisdb")
#Access(AccessType.PROPERTY)
public class Letter {
public enum PhoneticType {
VOWEL, SHORT, LONG, COMMON;
public static boolean contains(String s) { ... }
}
public enum PositionType {
ALL, INITIAL, MEDIAL, FINAL;
public static boolean contains(String s) { ... }
}
public enum CaseType {
ALL, LOWER, UPPER;
public static boolean contains(String s) { ... }
}
private int id;
private String name;
private String translit;
private String present;
private List<PhoneticType> phoneticTypes;
private CaseType caseType;
private PositionType positionType;
#Id
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 String getTranslit() { return translit; }
public void setTranslit(String translit) { this.translit = translit; }
public String getPresent() { return present; }
public void setPresent(String present) { this.present = present; }
public String getTypes() {
StringBuilder sb = new StringBuilder(); //
if (phoneticTypes!=null) for (PhoneticType type : phoneticTypes) sb.append(" ").append(type.name());
if (caseType!=null) sb.append(" ").append(caseType.name());
if (positionType!=null) sb.append(" ").append(positionType.name());
return sb.substring( sb.length()>0?1:0 );
}
public void setTypes(String types) {
List<PhoneticType> phoneticTypes = new ArrayList<PhoneticType>();
CaseType caseType = null;
PositionType positionType = null;
for (String val : Arrays.asList(types.split(" "))) {
String canonicalVal = val.toUpperCase();
if (PhoneticType.contains(canonicalVal)) phoneticTypes.add(PhoneticType.valueOf(canonicalVal));
else if (CaseType.contains(canonicalVal)) caseType = CaseType.valueOf(canonicalVal);
else if (PositionType.contains(canonicalVal)) positionType = PositionType.valueOf(canonicalVal);
}
this.phoneticTypes = phoneticTypes;
this.caseType = (caseType==null)? CaseType.ALL : caseType;
this.positionType = (positionType==null)? PositionType.ALL : positionType;
}
#Override
public String toString() { .... }
}
My Repository/DAO code:
package ...
import ...
#RepositoryRestResource
public interface LetterRepository extends CrudRepository<Letter, Integer> {
List<Letter> findByTypesLike(#Param("types") String types);
}
Hitting this URI: http://mytestserver.com:8080/greekLetters/6
and setting breakpoints on all the getters and setters, I can see that the properties are called in this order:
setId
setName
setPresent
setTranslit
setTypes
(getId not called)
getName
getTranslit
getPresent
(getTypes not called !!)
The json returned for the URI above reflects all the getters called, and there are no errors
{
"name" : "alpha",
"translit" : "`A/",
"present" : "Ἄ",
"_links" : {
"self" : {
"href" : "http://mytestserver.com:8080/letters/6"
}
}
}
But why is my getTypes() not being called and my JSON object missing the “types” attribute? I note that the setter is called, which makes it even stranger to me.
Any help would be appreciated!
Thanks in advance
That's probably because you don't have a field types, so getTypes() isn't a proper getter. Try adding this to your entity
#Transient
private String types;
I don't know how the inner works, but it's possible that the class is first scanned for its fields, and then a getter is called for each field. And since you don't have types field, the getter isn't called. Setter getting called could be a feature but I wouldn't be surprised if it is a bug, because findByTypesLike should translate to find Letters whose types field is like <parameter>, and types is not a field.
Another thing you can try, is to annotate that getter with #JsonInclude. Jackson 2 annotations are supported in Spring versions 3.2+ (also backported to 3.1.2).
I have a class that implements an interface. Why are the arraylist contents not stored in the database? Here is some code to illustrate the problem.
The class
#Entity
public class MyClass implements MyInterface {
#Id
#Indexed
public String id;
public String someField;
public MyClass(String id, String someField){
this.id = id;
this.someField = someField;
}
}
The interface
public interface MyInterface {
#Embedded
public List<String> mylist = new ArrayList<String>();
}
Test code
#Test
public void test() {
testInheritance();
}
public void testInheritance() {
MyClass myClass = new MyClass("test", "someField");
myClass.myList.add("wow");
MyClassDao dao = new MyClassDao();
dao.save(myClass);
}
public class MyClassDao extends BasicDAO<MyClass, ObjectId> {
public MyClassDao() {
super(MyClass.class, MorphiaManager.getMongoClient(), MorphiaManager.getMorphia(), MorphiaManager.getDB().getName());
}
}
Result in DB
{
"_id" : "test",
"className" : "gr.iti.mklab.simmo.util.MyClass",
"someField" : "someField"
}
Interfaces can only declare method signatures and constants (static final variables). What you want to use is an abstract base class from which you inherit.
Additional observations from your code:
The id should be ob the type ObjectId and is automatically indexed, you don't need the #Indexed
Attributes should be private or protected and you need to provide getters and setters for them
You need a default no-arg constructor in your entity class
I have been stacked in this place for few days. any help will be appreciated.
Here is my story:
I have a JPA entity class (ExtOffer), and Now I annotate it with JAXB annotation in order to do marshall/unmarshall by JAXB. And I also create a wrapper class(ExtOffers), which basically is a collection of ExtOffer.
And when I call JAXBContext.newInstance(ExtOffers.class), I got an IllegalAnnotationsException:JAXB annotation is placed on a method that is not a JAXB property.
I search google and some post says that it's due to annotate #XmlElement on wrong place.
But my class has #XmlAccessorType(XmlAccessType.NONE) annotation and only the getter method has been annotated with #Xmlelement.
below is my ExtOffer class and ExtOffers class:
//ExtOffer:
#Entity
#Table (name = "extoffer")
#XmlType(name = "ExtOfferType")
#XmlAccessorType(XmlAccessType.NONE)
public class ExtOffer {
public ExtOffer() {
}
#Id
#Column(name = "OfferID", nullable = false, unique = true, length = 32)
protected String offerId;
#Column(name = "HasMoreScreenShot", nullable = false, unique = false, length = 1)
private String hasMoreScreenShot;
public void setOfferId(String offerId) {
this.offerId = offerId;
}
#XmlElement(name="OfferID", required = true)
public String getOfferId() {
return offerId;
}
public void setHasMoreScreenShot(String hasMoreScreenShot) {
this.hasMoreScreenShot= hasMoreScreenShot;
}
#XmlElement(name = "HasMoreScreenShot")
public String GetHasMoreScreenShot() {
return hasMoreScreenShot;
}
}
//ExtOffers wrapper
#XmlRootElement(name="extoffers")
#XmlAccessorType(XmlAccessType.NONE)
public class ExtOfferWrapper {
private List<ExtOffer> extoffers;
public ExtOfferWrapper() {
}
#XmlElement(name="extoffer")
public List<ExtOffer> getExtoffers() {
return extoffers;
}
public void setExtoffers(List<ExtOffer> extoffers) {
this.extoffers = extoffers;
}
}
JAXB annotation is placed on a method that is not a JAXB property
this problem is related to the following location:
at #javax.xml.bind.annotation.XmlElement(nillable=false, name=HasMoreScreenShot, required=false, defaultValue=, type=class javax.xml.bind.annotation.XmlElement$DEFAULT, namespace=##default)
at com.symbio.fuhu.appstore.jpa.entity.ExtOffer
at public java.util.List com.symbio.fuhu.appstore.jaxb.mapping.wrapper.ExtOfferWrapper.getExtoffers()
at com.symbio.fuhu.appstore.jaxb.mapping.wrapper.ExtOfferWrapper
You have an upper case 'G'
#XmlElement(name = "HasMoreScreenShot")
public String GetHasMoreScreenShot() {
return hasMoreScreenShot;
}