@Valid, @ validated learning notes

1. brief introduction

1. @Validated： Can be used in type 、 Method and method parameters . But it can't be used in member properties （ Field ） On , Nested detection is not supported
2. @Valid： It can be used in methods 、 Constructors 、 Method parameters and member properties （ Field ） On , Support nested detection

2. introduce maven

springboot 2.3.0 It will not be imported automatically in the future jar package , So add the following maven,2.3 In the past, there was no need to introduce maven package

<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-validation</artifactId>
</dependency>

3. Use notes together

@Null  The limit can only be null
@NotNull  The limit must not be null
@AssertFalse  The limit must be false
@AssertTrue  The limit must be true
@DecimalMax(value)  The limit must be a number no greater than the specified value 
@DecimalMin(value)  The limit must be a number not less than the specified value 
@Digits(integer,fraction)  The limit must be a decimal , And the number of digits in the integer part cannot exceed integer, The number of decimal places cannot exceed fraction
@Future  The limit must be a future date 
@Max(value)  The limit must be a number no greater than the specified value 
@Min(value)  The limit must be a number not less than the specified value 
@Past  The limit must be a date in the past 
@Pattern(value)  The restriction must conform to the specified regular expression 
@Size(max,min)  The limit character length must be in min To max Between 
@Past  Verify the element value of the annotation （ The date type ） Earlier than the current time 
@NotEmpty  Verify that the element value of the annotation is not null It's not empty （ String length is not 0、 The set size is not 0）
@NotBlank  Verify that the element value of the annotation is not empty （ Not for null、 The length after removing the first space is 0）, differ @NotEmpty,@NotBlank It only applies to strings and will remove the space of strings when comparing 
@Email  Verify that the element value of the annotation is Email, You can also use regular expressions and flag Specify custom email Format 

4. Example

4.1 model

@Valid Definition schoole Property is for nested validation , Without this annotation, you can't verify school Properties that need to be verified inside the class .

public class UserVO {
    @NotNull(message = "id Can't be empty ." ,groups = {Insert.class})
    private Integer id;

    @NotBlank(message = "name Can't be empty .",groups = {Update.class})
    private String name;

    @NotNull(message = "schoole Can't be empty .")
    @Valid
    private Schoole schoole;


    @Min(value = 1,message = "age Not less than 1")
    @Max(value = 130,message = "age Not greater than 130")
    private int age;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public Schoole getSchoole() {
        return schoole;
    }

    public void setSchoole(Schoole schoole) {
        this.schoole = schoole;
    }

public class Schoole {

    @NotBlank(message = "name Can't be empty .",groups = {Update.class})
    private String name;
    @NotNull(message = "id Can't be empty ")
    private Integer id;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

4.3 Packet interface

Realization Default Interface otherwise @Validated({Update.class}) Use Update In groups , The default verification property of undefined groups will not take effect （ Like verification schoole Of @NotNull(message = “schoole Can't be empty .”)）

import javax.validation.groups.Default;
public interface Insert  extends Default {
}

public interface Update extends Default {
}

4.4controller

@Validated mark group when （Update.class） Only the verification annotation on the verification attribute needs to contain the interface （Update.class） To take effect , If group （Update.class） Realized Default If the interface needs to be verified, the verification annotation on the verification attribute does not define any group It will also take effect when .

@RestController
@RequestMapping("/valid")
public class TestValidController {
    private static final Logger LOG = LoggerFactory.getLogger(TestValidController.class);

    @RequestMapping("/test")
    public void testValid(@Validated({Update.class}) UserVO userVO){
        LOG.info("userVo:"+userVO);
    }


    @PostMapping("/test2")
    public void testValid2(@Validated() @RequestBody UserVO userVO){

        LOG.info("userVo:"+userVO);
    }



}

4.5 Use the global exception interceptor to intercept parameter verification exceptions

MethodArgumentNotValidException Anomaly caused by @RequestBody The decorated parameter has not been verified. Throw , Other exceptions that fail to pass the verification are thrown BindException.

@RestControllerAdvice
public class GlobalExceptionHandler {
    private Logger LOG= LoggerFactory.getLogger(GlobalExceptionHandler.class);



//BindException  Thrown if the verification parameters do not meet the conditions 
    @ExceptionHandler(BindException.class)
    public Object handleValidException(BindException e) {
        return ResponseUtil.fail(400,e.getBindingResult().getFieldError().getDefaultMessage());
    }

	//MethodArgumentNotValidException  @RequestBody  The decorated parameter has not been verified. Throw 
    @ExceptionHandler(MethodArgumentNotValidException.class)
    public Object handleValidException2(MethodArgumentNotValidException e) {
        return ResponseUtil.fail(400,e.getBindingResult().getFieldError().getDefaultMessage());
    }



    @ExceptionHandler(RuntimeException.class)
    @ResponseStatus(value = HttpStatus.INTERNAL_SERVER_ERROR)
    public ResponseUtil handleRuntimeException(RuntimeException ex) {
        int code = 500;
        String message = ex.getMessage();
        ex.printStackTrace();
        LOG.error(ex.getMessage());
        return ResponseUtil.fail(code,message);
    }

    @ExceptionHandler(Exception.class)
    @ResponseStatus(value = HttpStatus.INTERNAL_SERVER_ERROR)
    public ResponseUtil handleException(Exception ex) {
        int code = 500;
        String message = ex.getMessage();
        ex.printStackTrace();
        LOG.error(ex.getMessage());
        return ResponseUtil.fail(code,message);
    }


}