Spring boot : Failed to save List<String> - spring-boot

Question

Please I'm trying to save List in spring boot I failed to do it.
this is the entity :
#Column(name="services")
#ElementCollection
#NotBlank
private List<String> services = new ArrayList<String>();
This is Postman :
Postman result :
issue :
: No validator could be found for constraint 'javax.validation.constraints.NotBlank' validating type 'java.util.List<java.lang.String>'
I edit the function to save like this :
List<String> lstServices= new ArrayList<>();
carePost.getServices().forEach(item -> {
lstServices.add(item);
});
carePost.setServices(lstServices);
but still same error
Controller method :
#PostMapping("/addcarepost")
public ResponseEntity<?> createCarePost(#RequestBody CarePost carePost){
carePost.setCareserviceId(carePost.getCareserviceId());
List<String> lstServices= new ArrayList<>();
carePost.getService().forEach(item -> {
lstServices.add(item);
});
carePost.setService(lstServices);
carePostService.save(carePost);
return ResponseEntity.ok(new MessageResponse("CarePost registered successfully!"));
}
ServiceImpl :
#Override
public CarePost save(CarePost cp) {
return carePostRepository.save(cp) ; }

Answer 1

You should not use #NotBlank because:
#NotBlank can be applied only to text values and validates that the property is not null or whitespace.
instead you should use #NotEmpty because :
#NotEmpty validates that the property is not null or empty; can be applied to String, Collection, Map or Array values.
If your goal is to verify if in the array are some empty values, you can create a custom validator like shown here or you can use List<#NotBlank String> preferences;
Putting #NotBlank (or others validation annotation) at property level, will validate the property itself, if you wanna instead validate the element of a the property (in this case a collection)you have to put the annotation at the same element level (as shown on the top).
Source: Javax Validation