如何使用hibernate注释来验证枚举成员字段?以下内容不起作用:
enum UserRole { USER, ADMIN; } class User { @NotBlank //HV000030: No validator could be found for type: UserRole. UserRole userRole; }
请注意,您还可以创建一个验证器来检查String是否为枚举的一部分。
public enum UserType { PERSON, COMPANY } @NotNull @StringEnumeration(enumClass = UserCivility.class) private String title;
@Documented @Constraint(validatedBy = StringEnumerationValidator.class) @Target({ METHOD, FIELD, ANNOTATION_TYPE, PARAMETER, CONSTRUCTOR }) @Retention(RUNTIME) public @interface StringEnumeration { String message() default "{com.xxx.bean.validation.constraints.StringEnumeration.message}"; Class<?>[] groups() default {}; Class<? extends Payload>[] payload() default {}; Class<? extends Enum<?>> enumClass(); }
public class StringEnumerationValidator implements ConstraintValidator<StringEnumeration, String> { private Set<String> AVAILABLE_ENUM_NAMES; @Override public void initialize(StringEnumeration stringEnumeration) { Class<? extends Enum<?>> enumSelected = stringEnumeration.enumClass(); //Set<? extends Enum<?>> enumInstances = EnumSet.allOf(enumSelected); Set<? extends Enum<?>> enumInstances = Sets.newHashSet(enumSelected.getEnumConstants()); AVAILABLE_ENUM_NAMES = FluentIterable .from(enumInstances) .transform(PrimitiveGuavaFunctions.ENUM_TO_NAME) .toSet(); } @Override public boolean isValid(String value, ConstraintValidatorContext context) { if ( value == null ) { return true; } else { return AVAILABLE_ENUM_NAMES.contains(value); } } }
这很好,因为您不会丢失“错误值”的信息。您会收到类似的消息
值“ someBadUserType”不是有效的用户类型。有效的UserType值为:PERSON,COMPANY
编辑
对于那些想要非番石榴版本的人,它应该可以使用类似以下的功能:
public class StringEnumerationValidator implements ConstraintValidator<StringEnumeration, String> { private Set<String> AVAILABLE_ENUM_NAMES; public static Set<String> getNamesSet(Class<? extends Enum<?>> e) { Enum<?>[] enums = e.getEnumConstants(); String[] names = new String[enums.length]; for (int i = 0; i < enums.length; i++) { names[i] = enums[i].name(); } Set<String> mySet = new HashSet<String>(Arrays.asList(names)); return mySet; } @Override public void initialize(StringEnumeration stringEnumeration) { Class<? extends Enum<?>> enumSelected = stringEnumeration.enumClass(); AVAILABLE_ENUM_NAMES = getNamesSet(enumSelected); } @Override public boolean isValid(String value, ConstraintValidatorContext context) { if ( value == null ) { return true; } else { return AVAILABLE_ENUM_NAMES.contains(value); } } }