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JSR - 349 bean validation for Spring #RestController with Spring Boot

I am using Spring Boot 1.5.2.RELEASE and not able to incorporate JSR - 349 ( bean validation 1.1 ) for #RequestParam & #PathVariable at method itself.
For POST requests, if method parameter is a Java POJO then annotating that parameter with #Valid is working fine but annotating #RequestParam & #PathVariable with something like #NotEmpty, #Email not working.
I have annotated controller class with Spring's #Validated
There are lots of questions on SO and I have commented on this answer that its not working for me.
Spring Boot includes - validation-api-1.1.0.Final.jar and hibernate-validator-5.3.4.Final.jar .
Am I missing anything?
Example code ,
#RequestMapping(method = RequestMethod.GET, value = "/testValidated", consumes = MediaType.APPLICATION_JSON_VALUE, produces = MediaType.APPLICATION_JSON_VALUE)
public ResponseBean<String> testValidated(#Email #NotEmpty #RequestParam("email") String email) {
ResponseBean<String> response = new ResponseBean<>();
response.setResponse(Constants.SUCCESS);
response.setMessage("testValidated");
logger.error("Validator Not called");
return response;
}
Below handler is never called when I send empty values or not well formed email address for email & control always goes to with in testValidated method.
#ExceptionHandler(ConstraintViolationException.class)
#ResponseBody
#ResponseStatus(HttpStatus.BAD_REQUEST)
public ResponseBean handle(ConstraintViolationException exception) {
StringBuilder messages = new StringBuilder();
ResponseBean response = new ResponseBean();
exception.getConstraintViolations().forEach(entry -> messages.append(entry.getMessage() + "\n"));
response.setResponse(Constants.FAILURE);
response.setErrorcode(Constants.ERROR_CODE_BAD_REQUEST);
response.setMessage(messages.toString());
return response;
}
ResponseBean<T> is my application specific class.

I had asked the question after more than two days of unsuccessful hit & trial. Lots of confusing answers are out there because of confusions around Spring Validations and JSR validations, how Spring invokes JSR validators, changes in JSR standards & types of validations supported.
Finally, this article helped a lot.
I solved problem in two steps,
1.Added following beans to my Configuration - without these beans , nothing works.
#Bean
public MethodValidationPostProcessor methodValidationPostProcessor() {
MethodValidationPostProcessor mvProcessor = new MethodValidationPostProcessor();
mvProcessor.setValidator(validator());
return mvProcessor;
}
#Bean
public LocalValidatorFactoryBean validator() {
LocalValidatorFactoryBean validator = new LocalValidatorFactoryBean();
validator.setProviderClass(HibernateValidator.class);
validator.afterPropertiesSet();
return validator;
}
2.Placed Spring's #Validated annotation on my controller like below,
#RestController
#RequestMapping("/...")
#Validated
public class MyRestController {
}
Validated is - org.springframework.validation.annotation.Validated
This set up doesn't affected #Valid annotations for #RequestBody validations in same controller and those continued to work as those were.
So now, I can trigger validations like below for methods in MyRestController class,
#RequestMapping(method = RequestMethod.GET, value = "/testValidated" , consumes = MediaType.APPLICATION_JSON_VALUE, produces = MediaType.APPLICATION_JSON_VALUE)
public ResponseBean<String> testValidated(
#Email(message="email RequestParam is not a valid email address")
#NotEmpty(message="email RequestParam is empty")
#RequestParam("email") String email) {
ResponseBean<String> response = new ResponseBean<>();
....
return response;
}
I had to add another handler in exception handler for exception - ConstraintViolationException though since #Validated throws this exception while #Valid throws MethodArgumentNotValidException

Spring #Validated #Controller did not mapped when adding #Validated. Removal of any inheritance from controller itself did help. Otherwise Sabir Khan's answer worked and did help.

Problems trying to inherit SpringBoot REST annotations on concrete class

I am trying to configure an Interface with some REST methods with Spring Boot. But when I implement that interface on a concrete class, the #PathVariable or #RequestParam do not work properly unless I repeat the configuration on my concrete method (which I dont want because the interface is being generated by a maven plugin). Lets take a look at the interface and the concrete class.
#RequestMapping("employees")
public interface EmployeesResource {
#RequestMapping(method = RequestMethod.GET, produces = {"application/json"})
EmployeesResource.GetEmployeesResponse getEmployees(
#RequestParam(value = "pageNum", defaultValue = "0")
long pageNum,
#RequestParam(value = "pageSize", defaultValue = "10")
long pageSize)
throws Exception;
#RequestMapping(method = RequestMethod.GET, value = "{employeeId}", produces = {
"application/json"
})
EmployeesResource.GetEmployeesByEmployeeIdResponse getEmployeesByEmployeeId(
#PathVariable("employeeId")
long employeeId)
throws Exception;
}
Now lets take a look at the concrete class.
#RestController
public class EmployeesResourceImpl implements EmployeesResource {
#Override
public EmployeesResource.GetEmployeesByEmployeeIdResponse getEmployeesByEmployeeId(long employeeId) {
//omitted
return EmployeesResource.GetEmployeesByEmployeeIdResponse.withJsonOK(e);
}
#Override
public EmployeesResource.GetEmployeesResponse getEmployees(long pageNum, long pageSize)
throws Exception {
//omitted
return EmployeesResource.GetEmployeesResponse.withJsonOK(list);
}
}
When I make a call to http://127.0.0.1:8080/employees/1 it throws an exception.
java.lang.IllegalStateException: Optional long parameter 'employeeId' is present but cannot be translated into a null value due to being declared as a primitive type. Consider declaring it as object wrapper for the corresponding primitive type.
I know that this is because me employeeId is long and not Long, but that is not the question because if I add the #PathVariable("employeeId") to the method on the concrete class, it all works.
So, what I want is to not repeat the configuration from the interface into the concrete class. Same goes for the #RequestParam(value = "pageNum", defaultValue = "0").
I have googled a lot and did not found that capacity of inheritance of annotations inside Spring Boot. Any help would be appreciated.
EDIT: Andy Wilkinson suggested this post Spring MVC Annotated Controller Interface but the guy concluded that there is no way around this due to AOP injections that Spring does. Is there really nothing to do here?

Is it possible to validate #RequestParam in Spring MVC REST endpoint?

In Jersey 2 it is possible to do this:
#GET
#PATH("user/{email}")
public IDto getUser(#NotNull #Email #PathParam("email") String validEmail) {
return userManagementService.findUserByEmail(validEmail);
}
But I cannot make something similar to work in Spring MVC, it seems that the validation is only done when providing an object in #RequestBody or using an SpringMVC Form, for example the following won't work:
#RequestMapping(value="/user/{email}", method = RequestMethod.GET)
public #ResponseBody IDto getUser(#NotNull #Email #PathVariable String validEmail) {
return userManagementService.findUserByEmail(validEmail);
}
There are other similar questions, but those seem to be oriented to Spring MVC UI applications, in my case it is only a REST API which returns JSON response so I don't have any View to map/bind to the controller.

Seems it is possible, using #Validated.
Here's an example.
Based on OP's question, this should work:
#RestController
#Validated
public class MyController {
#GetMapping(value="/user/{email}")
public #ResponseBody IDto getUser(#NotNull #Email #PathVariable String validEmail) {
return userManagementService.findUserByEmail(validEmail);
}
}
In plain Spring implementations, it may be required to manually register the validator bean:
#Bean
public MethodValidationPostProcessor methodValidationPostProcessor() {
return new MethodValidationPostProcessor();
}

1- Simply add #Validated annotation at the top of your class.
2- Put whatever annotations for validations (#NotBlank, Min(1), etc.) before the #RequestParam annotation in your method signature.

The validated annotation from the org.springframework.validation.annotation.Validated package to validate a #PathVariable. Make sure the class annotated with #Validated.
#GetMapping("/name-for-day/{dayOfWeek}")
public String getNameOfDay(#PathVariable("dayOfWeek") #Min(1) #Max(7) Integer dayOfWeek) {
return dayOfWeek + "";
}

As far as I can tell, you cannot do this out-of-the-box with Spring.
Options:
Use a regular expression:
#RequestMapping(value="/user/{email:SOME_REXEXP}", method = RequestMethod.GET)
public #ResponseBody IDto getUser(#PathVariable String validEmail) {
return userManagementService.findUserByEmail(validEmail);
}
Use Hibernate Validator to validate the method. Either call the validator manually, or make Spring call it for you using AOP. See https://github.com/gunnarmorling/methodvalidation-integration

Controller should be annotated with spring's #Validated
So update your code with
#Validated
#RequestMapping(value="/user/{email}", method = RequestMethod.GET)
public #ResponseBody IDto getUser(
#NotNull
#Email
#PathVariable String validEmail) {
return userManagementService.findUserByEmail(validEmail);
}

Spring Web MVC - validate individual request params

I'm running a webapp in Spring Web MVC 3.0 and I have a number of controller methods whose signatures are roughly as follows:
#RequestMapping(value = "/{level1}/{level2}/foo", method = RequestMethod.POST)
public ModelAndView createFoo(#PathVariable long level1,
#PathVariable long level2,
#RequestParam("foo_name") String fooname,
#RequestParam(value = "description", required = false) String description);
I'd like to add some validation - for example, description should be limited to a certain length or fooname should only contain certain characters. If this validation fails, I want to return a message to the user rather than just throw some unchecked exception (which would happen anyway if I let the data percolate down to the DAO layer). I'm aware of JSR303 but have not worked with it and don't quite understand how to apply it in a Spring context.
From what I understand, another option would be to bind the #RequestBody to an entire domain object and add validation constraints there, but currently my code is set up to accept individual parameters as shown above.
What is the most straightforward way to apply validation to input parameters using this approach?

This seems to be possible now (tried with Spring 4.1.2), see https://raymondhlee.wordpress.com/2015/08/29/validating-spring-mvc-request-mapping-method-parameters/
Extract from above page:
Add MethodValidationPostProcessor to Spring #Configuration class:
#Bean
public MethodValidationPostProcessor methodValidationPostProcessor() {
return new MethodValidationPostProcessor();
}
Add #Validated to controller class
Use #Size just before #RequestParam
#RequestMapping("/hi")
public String sayHi(#Size(max = 10, message = "name should at most 10 characters long") #RequestParam("name") String name) {
return "Hi " + name;
}
Handle ConstraintViolationException in an #ExceptionHandler method

There's nothing built in to do that, not yet anyway. With the current release versions you will still need to use the WebDataBinder to bind your parameters onto an object if you want automagic validation. It's worth learning to do if you're using SpringMVC, even if it's not your first choice for this task.
It looks something like this:
public ModelAndView createFoo(#PathVariable long level1,
#PathVariable long level2,
#Valid #ModelAttribute() FooWrapper fooWrapper,
BindingResult errors) {
if (errors.hasErrors() {
//handle errors, can just return if using Spring form:error tags.
}
}
public static class FooWrapper {
#NotNull
#Size(max=32)
private String fooName;
private String description;
//getset
}
If you have Hibernate Validator 4 or later on your classpath and use the default dispatcher setup it should "Just work."
Editing since the comments were getting kind of large:
Any Object that's in your method signature that's not one of the 'expected' ones Spring knows how to inject, such as HttpRequest, ModelMap, etc, will get data bound. This is accomplished for simple cases just by matching the request param names against bean property names and calling setters. The #ModelAttribute there is just a personal style thing, in this case it isn't doing anything. The JSR-303 integration with the #Valid on a method parameter wires in through the WebDataBinder. If you use #RequestBody, you're using an object marshaller based on the content type spring determines for the request body (usually just from the http header.) The dispatcher servlet (AnnotationMethodHandlerAdapter really) doesn't have a way to 'flip the validation switch' for any arbitrary marshaller. It just passes the web request content along to the message converter and gets back a Object. No BindingResult object is generated, so there's nowhere to set the Errors anyway.
You can still just inject your validator into the controller and run it on the object you get, it just doesn't have the magic integration with the #Valid on the request parameter populating the BindingResult for you.

If you have multiple request parameters that need to be validated (with Http GET or POST). You might as well create a custom model class and use #Valid along with #ModelAttribute to validate the parameters. This way you can use Hibernate Validator or javax.validator api to validate the params. It goes something like this:
Request Method:
#RequestMapping(value="/doSomething", method=RequestMethod.GET)
public Model dosomething(#Valid #ModelAttribute ModelRequest modelRequest, BindingResult result, Model model) {
if (result.hasErrors()) {
throw new SomeException("invalid request params");
}
//to access the request params
modelRequest.getFirstParam();
modelRequest.getSecondParam();
...
}
ModelRequest class:
class ModelRequest {
#NotNull
private String firstParam;
#Size(min = 1, max = 10, message = "You messed up!")
private String secondParam;
//Setters and getters
public void setFirstParam (String firstParam) {
this.firstParam = firstParam;
}
public String getFirstParam() {
return firstParam;
}
...
}
Hope that helps.

How to create a default method in SpringMVC using annotations?

I can't find a solution to this, and it's driving me crazy. I have #Controller mapped that responds to several methods using #RequestMapping. I'd like to tag one of those methods as default when nothing more specific is specified. For example:
#Controller
#RequestMapping("/user/*")
public class UserController {
#RequestMapping("login")
public String login( MapModel model ) {}
#RequestMapping("logout")
public String logout( MapModel model ) {}
#RequestMapping("authenticate")
public String authenticate( MapModel model ) {}
}
So /user/login -> login method, /user/logout -> logout, etc. I'd like to make it so that if someone goes to /user then it routes to one of these methods. However, I don't see anything on #RequestMapping that would allow me to specify one of these methods as a default handler. I also don't see any other annotations that might be used on the class either to do this. I'm beginning to suspect it doesn't exist.
I'm using Spring 2.5.6. Is this solved in 3.0.0? I might just hack Spring to make it work because it's tremendously annoying this isn't more straightforward.
Thanks in Advance.

Take a look at this answer:
Spring MVC and annotated controllers issue
What if you annotate a method with:
#RequestMapping(method = RequestMethod.GET)
You can see an example here:
Spring 3.0 MVC + Hibernate : Simplified with Annotations – Tutorial
The same behavior can be seen here:
Spring Framework 3.0 MVC by Aaron Schram (look at page 21)

Short answer: I do not know how to simply specify one method as default with a simple tag.
But there is this ...
I do not know in which version of Spring this was implemented, but you can provide multiple values to #RequestMapping in 3.1.2. So I do this:
#Controller
#RequestMapping("/user")
public class UserController {
#RequestMapping(value = {"", "/", "/list"}, method = RequestMethod.GET)
public String listUsers(ModelMap model) { }
#RequestMapping(value = "/add", method = RequestMethod.POST)
public ModelAndView add(HttpServletRequest request, ModelMap model) { }
}
The following URLs then map to listUsers():
http://example.com/user
http://example.com/user/
http://example.com/user/list

I would create one default method without RequestMapping's value in there. Please see method defaultCall() below. You can then simply call them with URL: [yourhostname]/user
#Controller
#RequestMapping("/user")
public class UserController {
#RequestMapping(method = RequestMethod.GET)
public String defaultCall( MapModel model ) {
//Call the default method directly, or use the 'forward' String. Example:
return authenticate( model );
}
#RequestMapping("login")
public String login( MapModel model ) {}
#RequestMapping("logout")
public String logout( MapModel model ) {}
#RequestMapping("authenticate")
public String authenticate( MapModel model ) {}
}
Ref: Spring Framework Request Mapping

Simply using #RequestMapping("**") on your default method should work. Any more specific mappings should still pick up their requests. I use this method for setting up default methods sometimes. Currently using Spring v4.3.8.RELEASE.