Spring MVC参数校验详解（关于`@RequestBody`返回`400`）

@RequestMapping(value = "saveOrUpdate", method = RequestMethod.POST)
public String saveOrUpdate(HttpServletResponse response, @RequestBody Order order){
 CodeMsg result = null;
 try {
 result = orderService.saveOrUpdate(order);
 } catch (Exception e) {
 logger.error("save failed.", e);
 return this.renderString(response, CodeMsg.error(e.getMessage()));
 }
 return this.renderString(response, result);
}
@ResponseBody
@ResponseStatus(HttpStatus.BAD_REQUEST)
@ExceptionHandler(HttpMessageNotReadableException.class)
public CodeMsg messageNotReadable(HttpMessageNotReadableException exception, HttpServletResponse response){
 LOGGER.error("请求参数不匹配。", exception);
 return CodeMsg.error(exception.getMessage());
}

{
 "code": 1,
 "msg": "Could not read JSON: Failed to parse Date value '2017-03-' (format: \"yyyy-MM-dd HH:mm:ss\"): Unparseable date: \"2017-03-\" (through reference chain: com.test.modules.order.entity.Order[\"serveTime\"]); nested exception is com.fasterxml.jackson.databind.JsonMappingException: Failed to parse Date value '2017-03-' (format: \"yyyy-MM-dd HH:mm:ss\"): Unparseable date: \"2017-03-\" (through reference chain: com.test.modules.order.entity.Order[\"serveTime\"])",
 "data": ""
}

Indicates the annotated class assists a "Controller".

Serves as a specialization of {@link Component @Component}, allowing for implementation classes to be autodetected through classpath scanning.

It is typically used to define {@link ExceptionHandler @ExceptionHandler},
 * {@link InitBinder @InitBinder}, and {@link ModelAttribute @ModelAttribute}
 * methods that apply to all {@link RequestMapping @RequestMapping} methods.

One of {@link #annotations()}, {@link #basePackageClasses()},
 * {@link #basePackages()} or its alias {@link #value()}
 * may be specified to define specific subsets of Controllers
 * to assist. When multiple selectors are applied, OR logic is applied -
 * meaning selected Controllers should match at least one selector.

the default behavior (i.e. if used without any selector),
 * the {@code @ControllerAdvice} annotated class will
 * assist all known Controllers.

Note that those checks are done at runtime, so adding many attributes and using
 * multiple strategies may have negative impacts (complexity, performance).

@ResponseBody
@ControllerAdvice("com.api")
public class ApiExceptionHandler extends BaseClientController {
 private static final Logger LOGGER = LoggerFactory.getLogger(ApiExceptionHandler.class);
 /**
  *
  * @param exception UnexpectedTypeException
  * @param response
  * @return
  */
 @ResponseStatus(HttpStatus.BAD_REQUEST)
 @ExceptionHandler(UnexpectedTypeException.class)
 public CodeMsg unexpectedType(UnexpectedTypeException exception, HttpServletResponse response){
  LOGGER.error("校验方法太多，不确定合适的校验方法。", exception);
  return CodeMsg.error(exception.getMessage());
 }
 @ResponseStatus(HttpStatus.BAD_REQUEST)
 @ExceptionHandler(HttpMessageNotReadableException.class)
 public CodeMsg messageNotReadable(HttpMessageNotReadableException exception, HttpServletResponse response){
  LOGGER.error("请求参数不匹配，request的json格式不正确", exception);
  return CodeMsg.error(exception.getMessage());
 }
 @ResponseStatus(HttpStatus.BAD_REQUEST)
 @ExceptionHandler(Exception.class)
 public CodeMsg ex(MethodArgumentNotValidException exception, HttpServletResponse response){
  LOGGER.error("请求参数不合法。", exception);
  BindingResult bindingResult = exception.getBindingResult();
  String msg = "校验失败";
  return new CodeMsg(CodeMsgConstant.error, msg, getErrors(bindingResult));
 }
 private Map<String, String> getErrors(BindingResult result) {
  Map<String, String> map = new HashMap<>();
  List<FieldError> list = result.getFieldErrors();
  for (FieldError error : list) {
   map.put(error.getField(), error.getDefaultMessage());
  }
  return map;
 }
}

<dependency> 
 <groupId>org.hibernate</groupId> 
 <artifactId>hibernate-validator</artifactId> 
 <version>5.0.2.Final</version> 
</dependency>

<mvc:annotation-driven validator="validator" />
<bean id="validator" class="org.springframework.validation.beanvalidation.LocalValidatorFactoryBean">
 <property name="providerClass" value="org.hibernate.validator.HibernateValidator"/>
 <property name="validationMessageSource" ref="messageSource"/>
</bean>

public class AlipayRequest {
 @NotEmpty
 private String out_trade_no;
 private String subject;
 @DecimalMin(value = "0.01", message = "费用最少不能小于0.01")
 @DecimalMax(value = "100000000.00", message = "费用最大不能超过100000000")
 private String total_fee;
 /**
  * 订单类型
  */
 @NotEmpty(message = "订单类型不能为空")
 private String business_type;
 //....
}

@RequestMapping(value = "sign", method = RequestMethod.POST)
 public String sign(@Valid @RequestBody AlipayRequest params
 ){
  ....
 }

@ResponseStatus(HttpStatus.BAD_REQUEST)
@ExceptionHandler(Exception.class)
public CodeMsg ex(MethodArgumentNotValidException exception, HttpServletResponse response){
 LOGGER.error("请求参数不合法。", exception);
 BindingResult bindingResult = exception.getBindingResult();
 String msg = "校验失败";
 return new CodeMsg(CodeMsgConstant.error, msg, getErrors(bindingResult));
}
private Map<String, String> getErrors(BindingResult result) {
 Map<String, String> map = new HashMap<>();
 List<FieldError> list = result.getFieldErrors();
 for (FieldError error : list) {
  map.put(error.getField(), error.getDefaultMessage());
 }
 return map;
}

{
 "code": 1,
 "msg": "校验失败",
 "data": {
 "out_trade_no": "不能为空",
 "business_type": "订单类型不能为空"
 }
}

/**
 * Bean Validation 中内置的 constraint  
 * @Null 被注释的元素必须为 null  
 * @NotNull 被注释的元素必须不为 null  
 * @AssertTrue  被注释的元素必须为 true  
 * @AssertFalse 被注释的元素必须为 false  +
 * @Min(value)  被注释的元素必须是一个数字，其值必须大于等于指定的最小值  
 * @Max(value)  被注释的元素必须是一个数字，其值必须小于等于指定的最大值  
 * @DecimalMin(value) 被注释的元素必须是一个数字，其值必须大于等于指定的最小值  
 * @DecimalMax(value) 被注释的元素必须是一个数字，其值必须小于等于指定的最大值  
 * @Size(max=, min=) 被注释的元素的大小必须在指定的范围内  
 * @Digits (integer, fraction)  被注释的元素必须是一个数字，其值必须在可接受的范围内  
 * @Past 被注释的元素必须是一个过去的日期  
 * @Future  被注释的元素必须是一个将来的日期  
 * @Pattern(regex=,flag=) 被注释的元素必须符合指定的正则表达式  
 * Hibernate Validator 附加的 constraint  
 * @NotBlank(message =) 验证字符串非null，且长度必须大于0  
 * @Email 被注释的元素必须是电子邮箱地址  
 * @Length(min=,max=) 被注释的字符串的大小必须在指定的范围内  
 * @NotEmpty 被注释的字符串的必须非空  
 * @Range(min=,max=,message=) 被注释的元素必须在合适的范围内 
 */