数据校验

JSR303

SpringMVC支持使用JSR303进行快速校验,我们只需要给需要校验的bean加上响应的校验注解即可

使用步骤:

• 给Controller方法参数对象加上校验注解
• 加上@Valid声明需要校验
• 咱需要检验的参数后面紧跟一个BindingResult,即可获取到校验结果
• 判断校验结果是否出错,进一步来决定业务逻辑

基于AOP统一校验

1、基于AOP方式，统一获取校验错误并封装返回
@Aspect
@Component
@Order(2)
public class BindingResultAspect {
    @Pointcut("execution(public * com.gmall.controller.*.*(..))")
    public void BindingResult() {
    }

    @Around("BindingResult()")
    public Object doAround(ProceedingJoinPoint joinPoint) throws Throwable {
        Object[] args = joinPoint.getArgs();
        for (Object arg : args) {
            if (arg instanceof BindingResult) {
                BindingResult result = (BindingResult) arg;
                if (result.hasErrors()) {
                    return new CommonResult().validateFailed(result);
                }
            }
        }
        return joinPoint.proceed();
    }
}
2、自定义校验注解
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD,ElementType.PARAMETER})
@Constraint(validatedBy = FlagValidatorClass.class)
public @interface FlagValidator {
    String[] value() default {};

    String message() default "flag is not found";

    Class<?>[] groups() default {};

    Class<? extends Payload>[] payload() default {};
}
3、自定义校验注解解析器
public class FlagValidatorClass implements ConstraintValidator<FlagValidator,Integer> {
    private String[] values;
    @Override
    public void initialize(FlagValidator flagValidator) {
        this.values = flagValidator.value();
    }

    @Override
public boolean isValid(Integer value, 
ConstraintValidatorContext constraintValidatorContext) {
        boolean isValid = false;
        if(value==null){
            //当状态为空时使用默认值
            return true;
        }
        for(int i=0;i<values.length;i++){
            if(values[i].equals(String.valueOf(value))){
                isValid = true;
                break;
            }
        }
        return isValid;
    }
}