validation之自定义注解@Constraint

news2024/11/25 4:24:24

前言：

首先，接口参数校验应该都不陌生，大部分应该都会借助javax.validation进行快捷校验，一般都是在入参字段上添加@NotNull、@NotEmpty等，对于一些特殊的入参校验逻辑，可能不是很适用，现在介绍一下自定义注解方式。

依赖：

    <dependency>
      <groupId>org.hibernate.validator</groupId>
      <artifactId>hibernate-validator</artifactId>
      <version>6.0.10.Final</version>
    </dependency>

代码：

自定义注解：

import javax.validation.Constraint;
import javax.validation.Payload;

import java.lang.annotation.*;

@Target({ElementType.FIELD, ElementType.METHOD, ElementType.ANNOTATION_TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Constraint(validatedBy = {EnumValidator.class})
public @interface EnumValid {

    String message() default "";

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

    Class<? extends Payload>[] payload() default {};

    /**
     * 目标枚举类
     */
    Class<? extends Enum> target() default Enum.class;
}

实际校验类：

import com.honor.wpshowdemo.serverone.valid.EnumValid;
import org.apache.commons.lang.StringUtils;

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;
import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.Map;

public class EnumValidator implements ConstraintValidator<EnumValid, Object> {

    private EnumValid annotation;

    @Override
    public void initialize(EnumValid constraintAnnotation) {

        annotation = constraintAnnotation;
    }

    @Override
    public boolean isValid(Object value, ConstraintValidatorContext constraintValidatorContext) {
        boolean result = false;

        Class<?> cls = annotation.target();

        // target为枚举，并且value有值，才进行校验
        if (cls.isEnum() && (value != null)) {
            Object[] objects = cls.getEnumConstants();
            for (Object obj : objects) {
                //object类型转map
                Class<?> jqlEnum = obj.getClass();
                Field[] fs = jqlEnum.getDeclaredFields();
                Map<String, String> objMap = new HashMap<>();
                for (Field f : fs) {
                    f.setAccessible(true);
                    try {
                        objMap.put(f.getName(), f.get(obj).toString());
                    } catch (IllegalArgumentException | IllegalAccessException e) {
                        e.printStackTrace();
                    }
                }
                if (objMap.get("code") != null && StringUtils.equals(objMap.get("code"), String.valueOf(value))) {
                    result = true;
                    break;
                }
            }
        }
        return result;
    }
}

测试：

测试代码：

import lombok.Getter;

public enum TestEnum {

    FAILED(0),
    SUCCESS(1)
    ;

    @Getter
    private Integer id;

    TestEnum(Integer id) {
        this.id = id;
    }
}

import lombok.Data;

@Data
public class TestRequest {

    @EnumValid(target = TestEnum.class, message = "id不符合要求")
    private Integer id;
}

import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;

import javax.validation.Valid;

@RestController
public class TestController {

    @PostMapping("/test")
    public void test(@RequestBody @Valid TestRequest testRequest) {

    }
}

测试结果如下：