Java参数校验@Validated、@Valid介绍及使用详解

public String test(@RequestBody @Valid MyRequest req){};

//初始化对象时
String myString = new @Valid String();
//对象类型转化时
myString = (@Valid String) str;
//使用 implements 表达式时
class MyList<T> implements List<@Valid T> {...}
//使用 throws 表达式时
public void validateValues() throws @Valid ValidationFailedException{...}

@Pattern(regexp = "^[1-9]]\\d*$", message = "XX参数值必须是正整数")

public interface Student {
}

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

@Data
public class UserDTO {
    @NotBlank(message = "不能没有名称")
    private String name;
    @NotBlank(message = "老师不能没有手机号", groups = Teacher.class)
    private String phone;
    @NotEmpty(message = "学生不能没有书", groups = Student.clas)
    @Size(min = 2, message = "学生必须有两本书", groups = Student.class)
    private List<String> bookNames;
}

@RestController
public class ValidatedController {
    /**
     * 测试 校验student分组+默认分组
     */
    @PostMapping("student")
    public UserDTO validatedStudent(@Validated(value = {Student.class, Default.class}) @RequestBody UserDTO userDTO) {
        return userDTO;
    }
    /**
     * 测试 校验student分组+默认分组
     */
    @PostMapping("teacher")
    public UserDTO validatedTeacher(@Validated(value = {Teacher.class}) @RequestBody UserDTO userDTO) {
        return userDTO;
    }
    /**
     * 测试 分组校验  default
     */
    @PostMapping("default")
    public UserDTO validatedDefault(@Validated(value = {Default.class}) @RequestBody UserDTO userDTO) {
        return userDTO;
    }
    /**
     * 测试 分组校验 onlyStudent
     */
    @PostMapping("onlyStudent")
    public UserDTO validatedOnlyStudent(@Validated(value = {Student.class}) @RequestBody UserDTO userDTO) {
        return userDTO;
}

@Documented
//指定注解的处理类
@Constraint(validatedBy = {VersionValidatorHandler.class })
@Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER })
@Retention(RUNTIME)
public @interface ConstantVersion {
   String message() default "{constraint.default.const.message}";
   Class<?>[] groups() default {};
   Class<? extends Payload>[] payload() default {};
   String value();
}

public class VersionValidatorHandler implements ConstraintValidator<Constant, String> {
    private String constant;
    @Override
    public void initialize(Constant constraintAnnotation) {
        //获取设置的字段值
        this.constant = constraintAnnotation.value();
    }
    @Override
    public boolean isValid(String value, ConstraintValidatorContext context) {
        //判断参数是否等于设置的字段值，返回结果
        return constant.equals(value);
    }
}

@ConstantVersion (message = "verson只能为1.0.0",value="1.0.0")
String version;

@RestController
public class TestController {
    @RequestMapping("/test")
    public String createUser(@Valid User user, BindingResult bindingResult){
        if (bindingResult.hasErrors()){
            return bindingResult.getFieldError().getDefaultMessage();
        }
        return  "success";
    }
}

class Man{
    @Valid
    @Size(min = 1)
    private List<House> houses;
}
class House{
    @Length(min = 1,max = 10)
    private String name;
}

/**
* 全局异常处理器
*/
@Slf4j
@ControllerAdvice
public class GlobalExceptionHandler {
    /**
     * 异常处理
     */
    @ResponseBody
    @ExceptionHandler(value = Exception.class)
    public DataResult exceptionHandler(Exception e) {
        log.error("GlobalExceptionHandler.exceptionHandler , 异常信息",e);
        return DataResult.fail(e.getMessage());
    }
    /**
     * 业务异常
     */
    @ResponseBody
    @ExceptionHandler(value = BplCommonException.class)
    public DataResult bplCommonExceptionHandler(BplCommonException e) {
        log.warn("",e);
        return DataResult.fail(e.getMessage());
    }
    /**
     * 处理所有RequestBody注解参数验证异常
     */
    @ExceptionHandler(MethodArgumentNotValidException.class)
    @ResponseBody
    public DataResult handleMethodArgumentNotValidException(MethodArgumentNotValidException e){
        log.warn(e.getMessage());
        return DataResult.fail(e.getBindingResult().getAllErrors().get(0).getDefaultMessage());
    }
    /**
     * 处理所有RequestParam注解数据验证异常
     */
    @ExceptionHandler(BindException.class)
    public DataResult handleBindException(BindException ex) {
        FieldError fieldError = ex.getBindingResult().getFieldError();
        log.warn("必填校验异常:{}({})", fieldError.getDefaultMessage(),fieldError.getField());
        return DataResult.fail(ex.getBindingResult().getAllErrors().get(0).getDefaultMessage());
    }
}

if (e instanceof MethodArgumentNotValidException) {
	String errorMsg = ((MethodArgumentNotValidException) e)
		.getBindingResult()
		.getAllErrors()
        .stream()
		.map(DefaultMessageSourceResolvable::getDefaultMessage)
		.collect(Collectors.joining("，"));
	resp = R.builder()
		.code(ResultCodeEnum.BUSINESS_ERROR.getCode())
		.message(errorMsg).success(false)
		.build();
}