Java Spring Validator

1. Validation using Spring ' s Validator interface

Spring features a Validator interface that's can use to validate objects. the Validator interface works using a Errors object so it while validating, validators can report valid ation failures to the Errors object.

2. Data object:

public class Kmailpostform {    private Integer kid;    Public Kmailpostform () {    } public    Integer Getkid () {        return kid;    }    public void Setkid (Integer kid) {        this.kid = Kid;    }}

3. Validator:

Import Com.maduar.springbootdemo.form.kmailpostform;import Org.springframework.validation.errors;import Org.springframework.validation.validationutils;import Org.springframework.validation.validator;public Class Kmailpostformvalidator implements Validator {    @Override public    Boolean supports (class<?> clazz) {        Return KmailPostForm.class.equals (Clazz);    }    @Override public    Void Validate (Object target, Errors Errors) {        validationutils.rejectifempty (Errors, "Kid", " Kid.empty ");        Kmailpostform kmailpostform = (kmailpostform) target;        if (kmailpostform.getkid () = = null) {            errors.rejectvalue ("Kid", "Kid is null");        } else if (kmailpostform.getkid (). Intvalue () < 0) {            errors.rejectvalue ("Kid", "Kid < 0");}}}    

　　

4. Controller

@RestController @requestmapping (value = "/user") public class Usercontroller {    @InitBinder public    Void Initbinder (DataBinder databinder) {        databinder.setvalidator (new Kmailpostformvalidator ());    }    @PostMapping (value = "/hellopost/") public    httpentity<?> hellopost (@Valid @RequestBody kmailpostform Kmailpostform, bindingresult result) {        if (result.haserrors ()) {            return Responseentity.ok ("error");        }        Return Responseentity.ok ("OK");}    }

　　

A:springboot version 1.5.9.RELEASE

B:https://docs.spring.io/spring-framework/docs/current/spring-framework-reference/core.html#validation

Java Spring Validator