java–使用Spring通过条件验证对象字段

我有一个复杂的对象,其中包含两个UserPropertyForm对象：

public class ComplexUserForm {
int userType;
@Valid
UserPropertyForm property1;
UserPropertyForm property2;
...
}
public class UserPropertyForm {
@NotEmpty
@Length(max = 255)
private String title;
@NotEmpty
@Length(min = 100)
private String description;
...
}


我需要每次都验证property1,所以我将它标记为@Valid.
我只需要在userType == 2时验证property2

任何人都可以说我是否可以使用UserPropertyForm字段的注释以简单的方式验证property2？

谢谢你的帮助.

解决方法:

You can use this custom annotation above your class.
@ValidateIfAnotherFieldHasValue(
fieldName = "userType",
fieldValue = "2",
dependFieldName = "property2")
public class ComplexUserForm {
int userType;
@Valid
UserPropertyForm property1;
UserPropertyForm property2;


它只会在getUserType().equals(“2”)时验证property2.

错误消息将出现在property2.fieldname中,因此您需要
如果要从property2中捕获所有错误,请在JSP中.

public class ValidateIfAnotherFieldHasValueValidator
implements ConstraintValidator {
private String fieldName;
private String expectedFieldValue;
private String dependFieldName;
@Override
public void initialize(final ValidateIfAnotherFieldHasValue annotation) {
fieldName = annotation.fieldName();
expectedFieldValue = annotation.fieldValue();
dependFieldName = annotation.dependFieldName();
}
@Override
public boolean isValid(final Object value, final ConstraintValidatorContext ctx) {
if (value == null) {
return true;
}
try {
final String fieldValue = BeanUtils.getProperty(value, fieldName);
final Object dependFieldValue = PropertyUtils.getProperty(value, dependFieldName);
if (expectedFieldValue.equals(fieldValue)) {
ctx.disableDefaultConstraintViolation();
ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
Validator validator = factory.getValidator();
Set errorList = validator.validate(dependFieldValue);
for(ConstraintViolation error : errorList) { ctx.buildConstraintViolationWithTemplate(error.getMessageTemplate()) .addNode(dependFieldName+"."+error.getPropertyPath()) .addConstraintViolation();
}
return errorList.isEmpty();
}
} catch (final NoSuchMethodException ex) {
throw new RuntimeException(ex);
} catch (final InvocationTargetException ex) {
throw new RuntimeException(ex);
} catch (final IllegalAccessException ex) {
throw new RuntimeException(ex);
}
return true;
}
}


和：

@Target({ElementType.TYPE, ElementType.ANNOTATION_TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Constraint(validatedBy = ValidateIfAnotherFieldHasValueValidator.class)
@Documented
public @interface ValidateIfAnotherFieldHasValue {
String fieldName();
String fieldValue();
String dependFieldName();
String message() default "{ValidateIfAnotherFieldHasValue.message}";
Class[] groups() default {};
Class[] payload() default {};
@Target({ElementType.TYPE, ElementType.ANNOTATION_TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@interface List {
ValidateIfAnotherFieldHasValue[] value();
}
}