关键字
BindingResult、Spring AOP、自定义注解、自定义异常处理、ConstraintValidator
前言
在实际项目中，对接口的传如的参数需要做校验处理，原来都是在接口里面直接进行if判断，虽然简单，但是每个接口都要重复写，显得冗余；并且返回的数据也无法很好的自定义说明校验情况；如下；
@RequestMapping(value = { "/get/authcode" }, method = {RequestMethod.POST })
public Object getSignInAuthCode(@RequestBody AuthCodeReq authCodeReq) throws Exception {
//每个数据都要这样重复写
if(StringUtils.isBlank(authCodeReq.getMobile())){
//返回数据也是固定格式，无法知道究竟是什么数据校验没通过
return ResponseMessageEnum.ARGUMENT_EXCEPTION.toString();
}
//业务逻辑略
}
正文
0-封装全局数据校验功能的目的
1-避免每个接口重复使用if判断，显得冗余
2-可以自定义返回数据，告诉前端什么数据检验失败
1-POST请求业务逻辑(且数据以json格式放在body中传入)
1-将数据校验的具体内容放在POJO中，通过注解进行,见源码-01 2-当前端URL请求(POST请求，且数据以json格式放在body中传入)，且有数据校验失败时，传参BindException exception会接收校验失败的结果，见源码-02 3-使用Spring AOP的前置方法处理数据检验,见源码-03 3-1-自定义注解MyValidateAopAnnotation(见源码-04)，用于定位AOP的Pointcut(见源码-03) 3-2-AOP前置方法，根据joinPoint获取接口方法BindingResult参数值(见源码-03) 3-3-如果bindingResult.hasErrors()为true，则表明数据校验没有通过(见源码-03)，则直接抛出BindException异常() 3-4-在GlobalExceptionHandler类中的BindExceptionHandler方法，专门处理BindException异常，返回json数据(见源码-05)
2-GET请求
3-源码分析
//1-POJO
import org.hibernate.validator.constraints.NotEmpty;
import javax.validation.constraints.NotNull;
public class ValidateAuthCodeReq {
@NotEmpty(message = "手机号不能为空")//message将在接口返回数据中得以体现
private String mobile;//手机号
@NotEmpty(message = "验证码不能为空")
private String code;//验证码
public String getMobile() {
return mobile;
}
public void setMobile(String mobile) {
this.mobile = mobile;
}
public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
}
//2-controller层接口方法
@RestController
@RequestMapping(value="/api/shop/login")
public class ApiShopLoginController extends ApiShopBaseController {
//2-2-校验并绑定手机号
@MyValidateAopAnnotation//自定义注解，用户AOP定位方法
@RequestMapping(value = { "/validate/authcode" }, method = {RequestMethod.POST })
public Object validateAndBind( @Valid @RequestBody ValidateAuthCodeReq validateAuthCodeReq,BindingResult bindingResult) throws Exception {
//BindingResult封装了数据校验结果
//业务逻辑略
}
}
//3-AOP方法，统一处理数据校验
@Aspect
@Component
public class ExceptionAspect {
//根据自定义注解MyValidateAopAnnotation定位方法
@Pointcut("@annotation(com.hs.web.common.exception.MyValidateAopAnnotation)")
public void bindPointCut() {
}
@Before("bindPointCut()")
public void before(JoinPoint joinPoint) throws BindException {
// 接收到请求
ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
//获取请求的request
HttpServletRequest request = attributes.getRequest();
//获取BindingResult，并进行判断
Object[] args = joinPoint.getArgs();
BindingResult bindingResult = (BindingResult)args[args.length-1];
if(bindingResult.hasErrors()){
throw new BindException(bindingResult);
}
System.out.println("args[args.length-1]: "+ args[args.length-1]);
System.out.println("bindingResult" + bindingResult);
}
}
//4-自定义注解MyValidateAopAnnotation-目的是为了AOP定位
@Target({ METHOD, FIELD, CONSTRUCTOR, PARAMETER })
@Retention(RUNTIME)
@Documented
public @interface MyValidateAopAnnotation {
}
//5-全局异常处理类
import com.hs.common.util.json.JsonUtil;
@ControllerAdvice
@ResponseBody
public class GlobalExceptionHandler {
//数据校验
@ExceptionHandler(value=BindException.class)
public String BindExceptionHandler(HttpServletRequest request,BindException exception) throws Exception{
logger.warn(exception);
//1-封装异常说明
List<ObjectError> errorList = exception.getAllErrors();
StringBuffer sb = new StringBuffer();
for(ObjectError error : errorList){
sb.append("参数" + exception.getFieldError().getField() + "异常:" + exception.getFieldError().getDefaultMessage() + ";");
}
//2-封装返回参数
ExceptionResponseBean detailBean = new ExceptionResponseBean(
GlobalExceptionEnum.ERROR_DATA_VALIDATION.getCode(),
GlobalExceptionEnum.ERROR_DATA_VALIDATION.getMsg(),
sb.toString());
//3-以Json格式返回数据
return JsonUtil.toJson(detailBean).toString();
}
}
//6-异常情况枚举
import com.hs.common.util.json.JsonUtil;
public enum GlobalExceptionEnum {
OTHER_EXCEPTION(800, "出现异常", "其它异常，待识别", Exception.class),
ERROR_DATA_VALIDATION(801, "数据校验异常", "请求参数数据校验异常", BindException.class),
;
private int code;
private String msg;
private ExceptionResponseDetailBean data;
private Class exception;
private GlobalExceptionEnum(int code, String msg, String data, Class exception) {
this.code = code;
this.msg = msg;
this.data = new ExceptionResponseDetailBean(data);
this.exception = exception;
}
public int getCode() {
return code;
}
public String getMsg() {
return msg;
}
public ExceptionResponseDetailBean getData() {
return data;
}
public Class getException() {
return exception;
}
}
//7-ExceptionResponseBean异常返回POJO
public class ExceptionResponseBean {
private int code;
private String msg;
private ExceptionResponseDetailBean data;
public ExceptionResponseBean() {
super();
}
public ExceptionResponseBean(int code, String msg, String detail) {
super();
this.code = code;
this.msg = msg;
this.data = new ExceptionResponseDetailBean(detail);
}
public int getCode() {
return code;
}
public void setCode(int code) {
this.code = code;
}
public String getMsg() {
return msg;
}
public void setMsg(String msg) {
this.msg = msg;
}
public ExceptionResponseDetailBean getData() {
return data;
}
public void setData(ExceptionResponseDetailBean data) {
this.data = data;
}
}
//8-ExceptionResponseDetailBean异常返回明细POJO
public class ExceptionResponseDetailBean {
private String detail;
public ExceptionResponseDetailBean() {
super();
}
public ExceptionResponseDetailBean(String detail) {
super();
this.detail = detail;
}
public String getDetail() {
return detail;
}
public void setDetail(String detail) {
this.detail = detail;
}
}
4-应用示例
5-进一步优化校验
5-1-优点和问题
上面的数据校验已经进行分装，实现了和接口业务低耦合要求，并且可以自定义结果；但有一个问题：对于每一个POJO要校验的参数，都要重复指定message值，示例：@NotEmpty(message = "手机号不能为空") ；如果多个POJO对手机号验证，又会出现冗余情况
5-2-优化思路
自定义校验注解，对相同或类似的参数使用相同的自定义注解(见源码-01)自定义注解需要，自定义一个注解类(见源码-03)和一个ConstraintValidator实现类(见源码-03)
5-3-源码分析
//1-POJO
package com.hs.api.shopapp.entity.commom;
import com.hs.web.common.annotation.validation.MobileFormat;
public class AuthCodeReq {
@MobileFormat//使用自定义校验注解
private String mobile;//手机号
public String getMobile() {
return mobile;
}
public void setMobile(String mobile) {
this.mobile = mobile;
}
}
//2-自定义注解MobileFormat
@Documented
@Target({ElementType.METHOD, ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
@Constraint(validatedBy = MobileConstraintValidator.class)
public @interface MobileFormat {
String message() default "手机号格式不正确";
Class<?>[] groups() default {};
Class<? extends Payload>[] payload() default {};
@Target({ElementType.METHOD, ElementType.FIELD, ElementType.ANNOTATION_TYPE, ElementType.CONSTRUCTOR, ElementType.PARAMETER})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface List {
NotBlank[] value();
}
}
//3-重写ConstraintValidator接口，自定义校验规则
public class MobileConstraintValidator implements ConstraintValidator<MobileFormat,String>{
@Override
public void initialize(MobileFormat constraintAnnotation) {
}
//在当前方法指定校验规则
@Override
public boolean isValid(String value, ConstraintValidatorContext context) {
if(StringUtil.isBlank(value)){
return false;
}
return true;
}
}
//4-测试接口
@RestController
@RequestMapping(value="/api/shop/login")
public class ApiShopLoginController extends ApiShopBaseController {
@MyValidateAopAnnotation
@RequestMapping(value = { "/get/authcode" }, method = {RequestMethod.POST })
public Object getSignInAuthCode(@Valid @RequestBody AuthCodeReq authCodeReq,BindingResult bindingResult) throws Exception {
//业务逻辑略
}
}
5-4-应用示例
6-备注
6-1-@NotEmpty、@NotNull、@NotBlank 的区别
@NotEmpty 用在集合上面(不能注释枚举)@NotBlank用在String上面@NotNull用在所有类型上面
若对你有点帮助，请点赞！！！
