Is it possible to have empty RequestParam values use the defaultValue

Question

if I have a a request mapping similar to the following    RequestMapping value     test   method   RequestMethod POST   ResponseBody public void test  RequestParam value    i   defaultValue    10   int i        And then call this request with   http   example com test i    I get the error message     Failed to convert value of type  java lang String  to type  int   nested exception is java lang NumberFormatException  For input string        I can solve this by either stopping the javascript client from sending empty parameters  or by accepting string values and only parsing if they are not found to be blank   UPDATE  Later versions of spring now implement the originally desired behaviour   I ve just tested this in spring 4 3 5 and have found that the behaviour will now in fact turn the null value into the default value without raising a NumberFormatException  thus  my original mapping now works fine   I am not sure which version of spring this behavioural change was made

User · Answer

You can also do something like this -     RequestParam value   i   defaultValue    20   Optional lt Integer gt  i

User · Answer

You can keep primitive type by setting default value  in the your case just add  required   false  property    RequestParam value    i   required   false  defaultValue    10   int i   P S  This page from Spring documentation might be useful  Annotation Type RequestParam

User · Answer

You can set RequestParam  using generic class Integer instead of int   it will resolve your issue       RequestParam value   i   defaultValue    20   Integer i

User · Answer

You could change the  RequestParam type to an Integer and make it not required  This would allow your request to succeed  but it would then be null  You could explicitly set it to your default value in the controller method    RequestMapping value     test   method   RequestMethod POST   ResponseBody public void test  RequestParam value    i   required false  Integer i        if i    null            i   10                       I have removed the defaultValue from the example above  but you may want to include it if you expect to receive requests where it isn t set at all    http   example com test

User · Answer

This was considered a bug in 2013  https   jira spring io browse SPR-10180  and was fixed with version 3 2 2  Problem shouldn t occur in any versions after that and your code should work just fine

[java] Is it possible to have empty RequestParam values use the defaultValue?

Examples related to java

Examples related to spring

Examples related to spring-mvc