Validation on enum in spring request
As described in Difference between @Size, @Length and @Column(length=value)
@Size is a Bean Validation annotation that validates that the associated String has a value whose length is bounded by the minimum and maximum values.
You can only specify the the maximum required length for persisting enum value in your db. For example, if you define @Column(length = 8)
instead of @Size you will see workerType VARCHAR(8)
in your db definition correspondingly.
But there is a workaround for it: suppose you have
public enum WorkerType {PERMANENT , FULL_TIME, ...};
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Define a custom validation annotation:
@Target(ElementType.FIELD) @Retention(RetentionPolicy.RUNTIME) @Constraint(validatedBy = EnumSizeLimit.class) public @interface EnumSizeLimit { String message() default "{com.example.app.EnumSizeLimit.message}"; Class<?>[] groups() default {}; Class<? extends Payload>[] payload() default {}; Class<? extends Enum<?>> targetClassType(); }
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Implement a Validator:
public class EnumSizeLimitValidator implements ConstraintValidator < EnumSizeLimit , String > { private Set < String > allowedValues; @SuppressWarnings({ "unchecked", "rawtypes" }) @Override public void initialize(EnumSizeLimit targetEnum) { Class << ? extends Enum > enumSelected = targetEnum.targetClassType(); allowedValues = (Set < String > ) EnumSet.allOf(enumSelected).stream().map(e - > ((Enum << ? extends Enum << ? >> ) e).name()) .collect(Collectors.toSet()); } @Override public boolean isValid(String value, ConstraintValidatorContext context) { return value == null || (value.length>=0 && value.length<=8)) ? true : false; } }
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Define Field:
@EnumSizeLimit (targetClassType = WorkerType.class, message = "your message" private String workerType;
Mehraj Malik
Updated on June 16, 2022Comments
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Mehraj Malik almost 2 years
I have a request
WorkerRequest
in which there is anenum
which hasFULL_TIME
,MANAGER
and so on.In
WorkerRequest
how can I apply the length validation on this enum?Example: enum type should not be greater than 8 characters.
FULL_TIME
valid (8 characters)PERMANENT
invalid (9 characters)Currently if I put
javax.validation.constraints.Size
@Size(min = 0, max = 8, message = "Allowed length for workerType is 8.") @Enumerated(EnumType.STRING) private WorkerType workerType;
it throws an error :
HV000030: No validator could be found for constraint 'javax.validation.constraints.Size' validating type 'com.XX.XX.XX.WorkerType'. Check configuration for 'workerType'