Validate positive integers

Question

I want to allow only positive integers for number fields including zero. How can I define this validation using JSR 303 ?
I tried

1. @Min(value=0 message = "msg1") - But it allows float values like 1.2.

2. @Digits(fraction = 0, integer = 10, message ="msg2") - It accepts negative values.

3. @Min(value=0, message = "msg1" )
@Digits(fraction = 0, integer = 10, message ="msg2") - It works fine but sometimes both the messages i.e. msg1 and msg2 are displayed.

Any suggestions?

Thanks!

Dissever

Any particular reason you are not using an Integer field? – Feline

@Perception: I am working with legacy application and cannot change it right now. – Dissever

Use a custom constraint? - nonrepeatable.blogspot.com/2010/05/… – Bernice

@Paul: Dont we have a constraint in JSR to handle this? – Dissever

BTW, if you use hibernate-validator than you may create custom constraint which combine @Min and @Digits from 3rd option by using @ConstraintComposition(AND). When you add @ReportAsSingleViolation only your custom message will be shown. – Cassidycassie

@SlavaSemushin I think that'd be worth of another answer – Khajeh

Newer versions support @PositiveOrZero for this purpose – Iridize

Answer 1

Looks like you are looking for natural numbers, I think you can use the regex pattern to get the desired output. Something like

@Pattern(regexp = "[\\s]*[0-9]*[1-9]+",message="msg")

Salpingectomy

but sadly it cannot be applied for integer – Enidenigma

@Enidenigma for integer, isn't @Min the solution? I don't see the point in regexp for an integer – Khajeh

I want to have only 2 or more values for an integer that won't work using @Min or @Max right. – Purim

Answer 2

Just use the annotation @Min in your bean:

@Min(value = 0L, message = "The value must be positive")
private Double value;

Ruminant

what's the "L" mean in that value? – Leggett

"L" means explicit Long – Nepali

But since it's a Double, it should not be 0.0? – Cody

But if you have a look on the annotation, the value is long and in the doc they point that double and float are not supported – Felicita

Answer 3

You can use @Positive that works for the int and its wrappers too (ie Integer). This also will work for the BigInteger as well.

Harken

@Positive considers 0 as an invalid value. javaee.github.io/javaee-spec/javadocs/javax/validation/… – Feints

You can use it with the @Min annotation and this can provide a solution. – Harken

@VijayNandwana There is also @PositiveOrZero. javaee.github.io/javaee-spec/javadocs/javax/validation/… – Ladida

Answer 4

If you use hibernate-validator then you may create a custom constraint which combines @Min and @Digits from the 3rd option by using @ConstraintComposition(AND). When you add @ReportAsSingleViolation, only a custom message will be shown.

Cassidycassie

Answer 5

Its better to use range annotation like below for positive numbers

@Range(min = 0l, message = "Please select positive numbers Only")

For negative numbers

@Range(min = -9223372036854775808l, max = 0l, message = "Please select Negative numbers Only")

Arcograph

Why is it better? – Maud

Answer 6

Another kind of solution and in my personal opinion cleaner and easier to read.

@Positive
@Digits(integer = 5, fraction = 0)

Better

why did you choose 5 digits in your example? – Crampon

@Crampon to check the postal code, but you can introduce the number that you want – Interrelated

Answer 7

This is an example code from the answer https://mcmap.net/q/413295/-validate-positive-integers above

@Documented
@Min(value=0, message = "add a min msg" )
@Digits(fraction = 0, integer = 10, message ="add a digit msg")
@Target({ElementType.METHOD, ElementType.FIELD, ElementType.ANNOTATION_TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Constraint(validatedBy = {})
@ReportAsSingleViolation
public @interface NumberFormatValidator {

    String message() default "invalid number";

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

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

}

It use Constraint composition http://docs.jboss.org/hibernate/validator/4.3/reference/en-US/html_single/#validator-customconstraints-compound and @ReportAsSingleViolation to avoid display both messages

Hayward

Answer 8

Change the data time of your field from int to Integer and a message.properties file to set the message

Example: assuming your fieldName is myNumericField and belongs to a class called Test

1. Change the datatype:

   • change private int myNumericField; to private Integer myNumericField;

   • Update getters and setters to use/return Integer

2. Create custom message.properties file. This may appear to be more work but it's a more elegant and scalable solution rather than having the messages hardcoded in your annotations

   • Create a message.properties file under resources directory

   • Edit messages.properties and add the following line

   typeMismatch.Test.myNumericField=Please use integers only

   Remember to change Test and myNumericField for your class and field name

   • Edit your Application Context xml file and add the following tags before the <\beans> tag

   <bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource"> <property name="basenames" value="resources/messages" /> </bean>

Shirelyshirey

Answer 9

Using the following combination solved the issue for me:

  @NotNull
  @Range(min = 1)
  @JsonProperty("end_range")
  private Integer endRange;

Make sure to use Integer class instead of int for @NotNull to work.

Trachytic