My problem is with having Spring bind the data I get from a form to a JPA entity. The wierd part is, it works just fine if I do not look at the BindingResults. The BindingResults says there were binding errors when an empty string is passed in for the field graduation, but I know it does bind them correctly because when I don't check Hibernate updates the database perfectly. Is there a way to not have to write logic to circumnavigate the wrongly fired binding errors?
#Entity
#Table(name="child")
public class Child {
#Id
#Column(name="id")
private Integer childId;
#ManyToOne(fetch=FetchType.EAGER )
#JoinColumn(name="house", referencedColumnName="house")
private House house;
#NotNull()
#Past()
#Column(name="birthday")
private Date birthday;
#Column(name="graduation_date")
private Date graduationDay;
}
I have tried the following lines in a property editor to no avail
SimpleDateFormat dateFormat = new SimpleDateFormat("MMM dd, yyyy");
registry.registerCustomEditor(Date.class, new CustomDateEditor(dateFormat, true));
Here is the method signature for the controller method Handling the request
#Controller
#SessionAttributes(value="child")
#RequestMapping(value="child")
public class ChildModController {
#RequestMapping(value="save-child.do", params="update", method = RequestMethod.POST)
public #ResponseBody Map<String,?> updateChild(
HttpServletRequest request,
#Valid #ModelAttribute(value="child")Child child,
BindingResult results)
}
This is what I get from the BindingResult class as a message
09:01:36.006 [http-thread-pool-28081(5)] INFO simple - Found fieldError: graduationDay,
Failed to convert property value of type java.lang.String to required type java.util.Date for property graduationDay;
nested exception is org.springframework.core.convert.ConversionFailedException:
Failed to convert from type java.lang.String to type #javax.persistence.Column java.util.Date for value ';
nested exception is java.lang.IllegalArgumentException
Spring automatically binds simple object types like String and Number, but for complex objects like java.util.Date or your own defined types, you will need to use what is called a PropertyEditors or Converters, both could solve your problem.
Spring already has a predefiend PropertyEditors and Converters like #NumberFormat and #DateTimeFormat
You can use them directly on your fields like this
public class Child {
#DateTimeFormat(pattern="dd/MM/yyyy")
private Date birthday;
#DateTimeFormat(iso=ISO.DATE)
private Date graduationDay;
#NumberFormat(style = Style.CURRENCY)
private Integer myNumber1;
#NumberFormat(pattern = "###,###")
private Double myNumber2;
}
Spring also allows you to define your own type converters which you must use it combined with Spring ConversionService
For example if you have a Color class like this
public class Color {
private String colorString;
public Color(String color){
this.colorString = color;
}
}
You would define the color converter for example like this
public class StringToColor implements Converter<String, Color> {
public Color convert(String source) {
if(source.equal("red") {
return new Color("red");
}
if(source.equal("green") {
return new Color("green");
}
if(source.equal("blue") {
return new Color("blue");
}
// etc
return null;
}
}
To check more about converters check this, also check this to know the difference between Converters and PropertyEditors
Related
I am using MongoDBTempalate with Springboot and trying to aggregate data basis LocalDateTime in which I am getting this error : org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type [java.time.LocalDateTime] to type [java.util.Date]
I tried adding a custom convertor but it did not help, the code I added is :
`#Bean
public MongoCustomConversions customConversions(){
List<Converter<?,?>> converters = new ArrayList<>();
converters.add(DateToLocalDateTimeConverter.INSTANCE);
converters.add( LocalDateTimeToDateConverter.INSTANCE);
return new MongoCustomConversions(converters);
}
enum DateToLocalDateTimeConverter implements Converter<Date, LocalDateTime> {
INSTANCE;
#Override
public LocalDateTime convert(Date source) {
return ofInstant(source.toInstant(), systemDefault());
}
}
enum LocalDateTimeToDateConverter implements Converter<LocalDateTime, Date> {
INSTANCE;
#Override
public Date convert(LocalDateTime source) {
return Date.from(source.toInstant(ZoneOffset.UTC));
}
}`
Can someone tell me where have I gone wrong in creating the convertor, or is there some alternative apart from changing the LocalDateTime to Date in the code, as the occurance are very huge and refactoring might take a lot of time and effort
You can try this annotation on your entity or DTO, it will automatically format the date.
#Document(collection = "sample")
public class Foo{
#JsonFormat(shape = JsonFormat.Shape.STRING, pattern = 'yyyy-MM-dd HH:mm', locale = "en-PH")
private Date createdAt;
}
I am using Java Spring Boot #RestController with an object containing enum fields.
Spring automagically deserializes the JSON to the MyRequest object.
#RestController
public class MyController {
#PostMapping(path = "/operation")
public ResponseEntity<MyResponse> operation(#Valid #RequestBody MyRequest request) {
...
}
}
public class MyRequest {
private MyEnum1 field1;
private MyEnum2 field2;
private MyEnum3 field3;
private MyEnum4 field4;
private MyEnum5 field5;
private MyEnum6 field6;
... // really a lot of various enum fields!
}
public enum MyEnum1 {
VAL1, VAL2, VAL3;
}
The problem is that if the JSON contains completely invalid value of the enum field, the deserializer silently converts them to null, without any exception.
{
"field1": "BLAHBLAH",
...
}
This is user-unfriendly and treacherous.
I know that I may write custom JSON deserializers for each enum, but the solution is cumbersome and non-elegant.
Is there a way to globally set the JSON enum deserializer to a "strict mode", so if the value is invalid it throws an exception? If so, how and where?
That feature should be disabled by default.
But if you want to set it explicitly you can do it like this:
in your properties:
spring.jackson.deserialization.read-unknown-enum-values-as-null=false
or as an alternative in a configuration class (actually any bean would work, just make sure it happens early):
#Autowired
public void configureJackson(ObjectMapper objectMapper) {
objectMapper.disable(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL);
}
Because it should actually be like this by default, I am wondering why it is not for you. Do you enable it somewhere? Which Spring Boot version are you using?
Having something like:
#Getter #Setter
public static class Entity {
private int hash;
private LocalDateTime createdTime;
}
and
#Getter #Setter
public static class DTO {
private String hash;
private String createdTime;
}
I need birectional mapping so I should be able to map Entity -> DTO -> Entity. In this example the property type happens to be LocalDateTime but could be any type that needs parsing from String or so (just to say that I am not after better way to map LocalDateTime but in general).
There are no problems in mapping. I create TypeMap, add Converter and for LocalDateTime a Provider also since it does note have public default constructor. Something like here.
If I had in my DTO also LocalDateTime createdTime(or String createdTime in my Entity) then ModelMapper.validate() would be happy. But I do not have and I need to create all the converting stuff.
All this leads to ModelMapper.validate() to complain:
Unmapped destination properties found in TypeMap[DTO -> Entity]:
org.example.test.modelmapper.validation.TestIt$Entity.setCreatedTime()
The code I currently use for validating mapping for LocalDateTime case is:
ModelMapper mm = new ModelMapper();
mm.createTypeMap(Entity.class, DTO.class);
mm.createTypeMap(DTO.class, Entity.class);
mm.createTypeMap(String.class, LocalDateTime.class)
.setPropertyProvider(localDateTimeProvider);
mm.addConverter(toStringDate);
mm.validate();
(so I am not doing any actual mapping but validating the mapping)
with
Provider<LocalDateTime> localDateTimeProvider =
new AbstractProvider<LocalDateTime>() {
#Override
public LocalDateTime get() {
return LocalDateTime.now();
}
};
and
Converter<String, LocalDateTime> toStringDate = new AbstractConverter<>() {
#Override
protected LocalDateTime convert(String source) {
return LocalDateTime.parse(source);
}
};
Ask for more details/code. I'll update question as needed
The setPropertyProvider method allows to specify a Provider to be used for providing instances of mapped properties within a TypeMap.
So when you write:
mm.createTypeMap(String.class, LocalDateTime.class)
.setPropertyProvider(localDateTimeProvider);
It does not fit the case because we are not using this provider in the mapping of a property of the String type to a property of a LocalDateTime type. It should rather be moved above to be associated with the DTO -> Entity TypeMap (The error message is by the way a good hint about that). So it should rather be.
mm.createTypeMap(DTO.class, Entity.class)
.setPropertyProvider(localDateTimeProvider);
Which makes perfect sense because we are using the provider to provide instance for the mapping of a String property of the DTO (String createdTime;) to a LocalDateTime property of the Entity (LocalDateTime createdTime;).
On the other hand the converter should be added to the ModelMapper before the corresponding provider.
Also leaving in mm.createTypeMap(String.class, LocalDateTime.class), my compiler complains that a similar typemap already exist and there is no need to create a new one. So with that I can discard it.
With these two changes, my bean looks like:
#Bean
ModelMapper demoModelMapper() {
Provider<LocalDateTime> localDateTimeProvider =
new AbstractProvider<LocalDateTime>() {
#Override
public LocalDateTime get() {
return LocalDateTime.now();
}
};
Converter<String, LocalDateTime> toStringDate = new AbstractConverter<String,
LocalDateTime>() {
#Override
protected LocalDateTime convert(String source) {
return LocalDateTime.parse(source);
}
};
ModelMapper mm = new ModelMapper();
mm.createTypeMap(Entity.class, DTO.class);
mm.addConverter(toStringDate);
mm.createTypeMap(DTO.class, Entity.class)
.setPropertyProvider(localDateTimeProvider);
mm.validate();
return mm;
}
Notice that I am calling validate() before returning the bean. This works for me. Please test and see on your side.
As in answer from alainlompo I had to move the adding of converter before the creation of type map.
But I also had to remove the provider part because it seemed to cause all string fields to be mapped as LocalDateTime so I got errors like:
org.modelmapper.MappingException: ModelMapper mapping errors:
1) The provided destination instance 2020-01-05T17:28:22.088694 is not of the required type int.
Above I think means that ModelMapper tried to populate field hash with a string representing LocalDateTime.
It seems that the provider is not needed at all. So my final code with just a converter added:
ModelMapper mm = new ModelMapper();
mm.createTypeMap(Entity.class, DTO.class);
mm.addConverter(toStringDate);
mm.createTypeMap(DTO.class, Entity.class);//.setPropertyProvider(localDateTimeProvider);
mm.validate();
This actually means that I asked a bit wrong question claiming that I need to use the provider
What is the correct way to register a custom deserializer for a path variable in Spring web reactive?
Example:
#GetMapping("test/{customType}")
public String test(#PathVariable CustomType customType) { ...
I tried ObjectMapperBuilder, ObjectMapper and directly via #JsonDeserialize(using = CustomTypeMapper.class) but it wont register:
Response status 500 with reason "Conversion not supported."; nested exception is org.springframework.beans.ConversionNotSupportedException: Failed to convert value of type 'java.lang.String' to required type '...CustomType'; nested exception is java.lang.IllegalStateException: Cannot convert value of type 'java.lang.String' to required type '...CustomType': no matching editors or conversion strategy found
For path variables deserialization you don't need to involve jackson, you can use org.springframework.core.convert.converter.Converter
For example:
#Component
public class StringToLocalDateTimeConverter
implements Converter<String, LocalDateTime> {
#Override
public LocalDateTime convert(String source) {
return LocalDateTime.parse(
source, DateTimeFormatter.ISO_LOCAL_DATE_TIME);
}
}
#GetMapping("/findbydate/{date}")
public GenericEntity findByDate(#PathVariable("date") LocalDateTime date) {
return ...;
}
Here's an article with examples
I ended up using #ModelValue because it semantically is not a deserialization, just parsing a key.
#RestController
public class FooController {
#GetMapping("test/{customType}")
public String test(#ModelAttribute CustomType customType) { ... }
}
#ControllerAdvice
public class GlobalControllerAdvice {
#ModelAttribute("customType")
public CustomType getCustomType(#PathVariable String customType) {
CustomeType result = // map value to object
return result;
}
}
Good evening, I'm trying to use Hibernate Validator, in the following scenario:
public class Car {
#NotNull
private String manufacturer;
#NotNull
#Size(min = 2, max = 14)
private String licensePlate;
#Min(2)
private int seatCount;
//setters and getters....
}
and I am trying to validate its attributes as follows:
public class CarMain {
public static Validator validator;
public static void main(String[] args) {
ValidatorFactory factory = Validation. buildDefaultValidatorFactory() ;
validator = factory. getValidator();
Car car = new Car(null,null,0);
Set<ConstraintViolation<Car>> st= validator.validate(car);
while(st.iterator.hasNext()){
ConstraintViolation<Car> cv = st.iterator.next();
System.out.println("Value: ("+cv.getInvalidValue()+") -->"+cv.getMessage());
System.out.println("Attribute: "+cv.getPropertyPath());
}
}
Here the whole entity is validated and the invalid values with the validation message and property path are displayed.
My question is:"Is it possible to validate only one attribute at a time with Hibernate Validator? Like I don't have to work with the whole object to validate it.
The Validator interface defines also a [Validator.validateProperty][1] method where you explicitly specify the property to validate. Mind you, you still need the object instance and you need to know the property you want to validate. This method is for example used by the integration of Bean Validation into JSF. Whether it makes sense to use it inm your case, will depend on your use case? Why don't you want to validate the whole object?
BTW, there is also Validator.validateValue which does not require an actual bean instance.