2.5 - @RequestParam not behaving like it ought to

[MountjoyJ]

Hello

I'm a little new to 2.5, but I suspect @RequestParam is throwing an exception when it shouldn't (with required=false, and when not passed a parameter). Here's my code:

@RequestMapping("/")
public ModelAndView index(
@RequestParam(value="foo", required=false) int id) {
ModelAndView mav = new ModelAndView("myview");
mav.addObject("message", id);
return mav;
}

Note the "required=false"! When called, I get the exception below.

Looking at the source for AnnotationMethodHandlerAdapter I see on line 549:
args[i] = converter.convertIfNecessary(paramValue, param.getParameterType());

Either convertIfNecessary should not throw an exception on null param, or we need a check before this method (on paramRequired), or I'm wrong and misunderstanding something :-)

Please advise.
Thanks
Jon

org.springframework.web.util.NestedServletExceptio n: Request processing failed; nested exception is org.springframework.beans.TypeMismatchException: Failed to convert value of type [null] to required type [int]; nested exception is java.lang.IllegalArgumentException: Cannot convert value of type [null] to required type [int]: no matching editors or conversion strategy found



...


org.springframework.beans.TypeMismatchException: Failed to convert value of type [null] to required type [int]; nested exception is java.lang.IllegalArgumentException: Cannot convert value of type [null] to required type [int]: no matching editors or conversion strategy found
org.springframework.beans.SimpleTypeConverter.conv ertIfNecessary(SimpleTypeConverter.java:50)

[Mike Bingham]

Internally, the default CustomNumberEditor registered in Spring for the primitive int type does not allow empty or null values, so an exception can occur even when you specify "required=false" for @RequestParam. You could use the java.lang.Integer wrapper instead for your parameter type (which allows null/empty values), or possibly create a custom editor which sets a default value on the primitive parameter for an empty or null input. The following thread has more discussion on the latter approach:

http://forum.springframework.org/showthread.php?t=28155

[MountjoyJ]

Thanks Mike - that did it..