Difference between @size(max = value ) and @min(value) and @max(value)

Question

I want to do some domain validation. In my object I have one integer.

Now my question is: if I write

@Min(SEQ_MIN_VALUE) @Max(SEQ_MAX_VALUE) private Integer sequence; 

and

 @Size(min = 1, max = NAME_MAX_LENGTH)  private Integer sequence; 

If it's an integer which one is proper for domain validation?
Can anybody explain me what is the difference between them?

Thanks.

Answer 1

@Min and @Max are used for validating numeric fields which could be String(representing number), int, short, byte etc and their respective primitive wrappers.

@Size is used to check the length constraints on the fields.

As per documentation @Size supports String, Collection, Map and arrays while @Min and @Max supports primitives and their wrappers. See the documentation.

Answer 2

package com.mycompany;  import javax.validation.constraints.Min; import javax.validation.constraints.NotNull; import javax.validation.constraints.Size;  public class Car {      @NotNull     private String manufacturer;      @NotNull     @Size(min = 2, max = 14)     private String licensePlate;      @Min(2)     private int seatCount;      public Car(String manufacturer, String licencePlate, int seatCount) {         this.manufacturer = manufacturer;         this.licensePlate = licencePlate;         this.seatCount = seatCount;     }      //getters and setters ... } 

@NotNull, @Size and @Min are so-called constraint annotations, that we use to declare constraints, which shall be applied to the fields of a Car instance:

manufacturer shall never be null

licensePlate shall never be null and must be between 2 and 14 characters long

seatCount shall be at least 2.