Java 模型注释能否验证两个字段

我有这个模型课

@Document(collection = "MyClass")
public class MyClass implements Persistable<UUID> {

    @NotEmpty(groups = { Create.class})
    private String field1;

    @NotEmpty(groups = { Create.class})
    private String field2;
}

现在在创建过程中，我想检查field1是否为空，field2是否为空，但两者都不应为空

---

我可以通过预先存在的注释或实现ConstraintValidator的自定义注释来实现这一点，或者我必须在我的服务层中进行验证

您可以创建自定义注释，并使用该注释在create类中进行验证

自定义批注：

@Target({TYPE, ANNOTATION_TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Constraint(validatedBy = CustomAnnotationValidator.class)
@Documented
public @interface CustomAnnotation {
    String message() default "One of field1 or field2 required";  //can make use of properties file to interpolate message

    String field1();    
    String field2();

}

然后在验证程序impl中：

public class CustomAnnotationValidator implements ConstraintValidator<CustomAnnotation, Object> {

private String field1Holder;
private String field2Holder;

@Override
public void initialize(CustomAnnotation constraintAnnotation) {
    field1Holder = constraintAnnotation.field1();
    field2Holder = constraintAnnotation.field2();
}

@Override
public boolean isValid(Object value, ConstraintValidatorContext context) {
    try {
        final String field1 = BeanUtils.getProperty(value, field1Holder);
        final String field2 = BeanUtils.getProperty(value, field2Holder);
        return !(field1 == null && field2 == null); //your validation logic
    } catch (Exception e) {
        log.error("Error validating object", e);
        return false;
    }
}

---

可以创建自定义类级别约束。

public class CustomAnnotationValidator implements ConstraintValidator<CustomAnnotation, Object> {

private String field1Holder;
private String field2Holder;

@Override
public void initialize(CustomAnnotation constraintAnnotation) {
    field1Holder = constraintAnnotation.field1();
    field2Holder = constraintAnnotation.field2();
}

@Override
public boolean isValid(Object value, ConstraintValidatorContext context) {
    try {
        final String field1 = BeanUtils.getProperty(value, field1Holder);
        final String field2 = BeanUtils.getProperty(value, field2Holder);
        return !(field1 == null && field2 == null); //your validation logic
    } catch (Exception e) {
        log.error("Error validating object", e);
        return false;
    }
}