SpringBoot + validation 接口参数校验的思路详解

        有参数传递的地方都少不了参数校验。在web开发中，前端的参数校验是为了用户体验，后端的参数校验是为了安全。试想一下，如果在controller层中没有经过任何校验的参数通过service层、dao层一路来到了数据库就可能导致严重的后果，最好的结果是查不出数据，严重一点就是报错，如果这些没有被校验的参数中包含了恶意代码，那就可能导致更严重的后果。

实践

一、引入依赖

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

二、使用校验

在controller层的参数校验可以分为两种场景：

单个参数校验
实体类参数校验

2.1 单参数校验

/**
* 参数校验测试 控制类
* @author oyc
*/
@RestController
@RequestMapping("user")
@Validated
public class RequestParamsValidatedController {

private Logger logger = LoggerFactory.getLogger(this.getClass());

@GetMapping
public User test(@NotNull(message = "姓名不能为空") String name,
     @NotNull(message = "年龄不能为空") @Max(value = 99, message = "不能大于200岁") Integer age) {
 logger.info("name:" + name + " -age:" + age);
 return new User(name, age);
}
}

2.2 实体类参数校验

/**
* 参数校验测试 控制类
* @author oyc
*/
@RestController
@RequestMapping("user")
@Validated
public class RequestParamsValidatedController {

private Logger logger = LoggerFactory.getLogger(this.getClass());

@PostMapping
public User save(@Validated User user) {
 logger.info(user.toString());
 return user;
}
}

package com.oycbest.springbootvalidated.vo;

import javax.validation.constraints.*;
import java.io.Serializable;

/**
* 用户实体类
* @author oyc
*/
public class User implements Serializable {
private String userId;

@NotNull(message = "用户名不能为空")
private String userName;

@NotNull(message = "年龄不能为空")
@Max(value = 100, message = "年龄不能大于100岁")
private int age;

@NotNull(message = "邮箱不能为空")
@Email(message = "邮箱格式不正确")
private String email;

@NotNull(message = "电话号码不能为空")
private String phoneNumber;

public User(@NotNull(message = "用户名不能为空") String userName, int age) {
 this.userName = userName;
 this.age = age;
}

public User() {
}

public User(String userId, @NotNull(message = "用户名不能为空") String userName, int age, String email, String phoneNumber) {
 this.userId = userId;
 this.userName = userName;
 this.age = age;
 this.email = email;
 this.phoneNumber = phoneNumber;
}

public String getUserId() {
 return userId;
}

public void setUserId(String userId) {
 this.userId = userId;
}

public String getUserName() {
 return userName;
}

public void setUserName(String userName) {
 this.userName = userName;
}

public int getAge() {
 return age;
}

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

public String getEmail() {
 return email;
}

public void setEmail(String email) {
 this.email = email;
}

public String getPhoneNumber() {
 return phoneNumber;
}

public void setPhoneNumber(String phoneNumber) {
 this.phoneNumber = phoneNumber;
}

@Override
public String toString() {
 return "User{" +
   "userId='" + userId + '\'' +
   ", userName='" + userName + '\'' +
   ", age=" + age +
   ", email='" + email + '\'' +
   ", phoneNumber='" + phoneNumber + '\'' +
   '}';
}
}

2.3 定义统一异常处理

package com.oycbest.springbootvalidated.exception;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;
import org.springframework.validation.BindException;
import org.springframework.validation.FieldError;
import org.springframework.validation.beanvalidation.MethodValidationPostProcessor;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.ResponseStatus;

import javax.validation.ConstraintViolation;
import javax.validation.ConstraintViolationException;
import javax.validation.ValidationException;
import java.util.List;
import java.util.Set;

/**
* 全局异常处理
*
* @author oyc
*/
@ControllerAdvice
@Component
public class GlobalExceptionHandler {
private Logger logger = LoggerFactory.getLogger(this.getClass());

@Bean
public MethodValidationPostProcessor methodValidationPostProcessor() {
 return new MethodValidationPostProcessor();
}

@ExceptionHandler
@ResponseBody
@ResponseStatus(HttpStatus.BAD_REQUEST)
public String handle(ValidationException exception) {
 logger.error("请求异常：" + exception.getMessage());
 if (exception instanceof ConstraintViolationException) {
  ConstraintViolationException exs = (ConstraintViolationException) exception;

Set<ConstraintViolation<?>> violations = exs.getConstraintViolations();
  for (ConstraintViolation<?> item : violations) {
   //打印验证不通过的信息
   logger.error("请求异常：" + item.getMessage());
  }
 }
 return "请求异常： " + exception.getMessage();
}

@ResponseBody
@ExceptionHandler(value = BindException.class)
public String bindException(Exception e) {
 if (e instanceof BindException) {
  BindException exs = (BindException) e;
  List<FieldError> fieldErrors = exs.getFieldErrors();
  for (FieldError item : fieldErrors) {
   logger.error("请求异常：" + item.getDefaultMessage());
  }
 }
 logger.error("数据绑定异常：" + e.getMessage());
 return "数据绑定异常";
}

@ResponseBody
@ExceptionHandler(value = Exception.class)
public String defaultException(Exception e) {
 logger.error("请求异常：" + e.getMessage());
 return "请求异常 " + e.getMessage();
}

}

三、约束性注解(简单)说明

来源：https://blog.csdn.net/u014553029/article/details/109192520