Spring MVC - How to get list of @RequestMethod method parameters (possibly by @RequestParam attribute)

Question

I have a Spring MVC controller with the following method:

    @RequestMapping(value = {"/filter"}, method = RequestMethod.GET)
    @ResponseBody
    public List<MetricType> getMetricTypes(    
            @RequestParam(value = "subject", required = false) Long subjectId,
            @RequestParam(value = "area", required = false) Long areaId,
            @RequestParam(value = "onlyImmediateChildren", required = false) Boolean onlyImmediateChildren,   
            @RequestParam(value = "componentGroup", required = false) Long componentGroupId    
            ) throws Exception
    {
        //Some code
    }

Is it possible to get the list of parameters of the current method programmatically (e.g. by @RequestParam annotation)? Solution should work without debug symbols. Method name can be hardcoded if required.

I am trying to check if the query string includes invalid parameters (e.g. because of typo). I am going to compare query parameter names from request with query parameter names from the method signature (if possible).

UPDATED

Solution should work for optional (required=false) parameters as well.

Many thanks

Maxim

Why would you want to accept typo'ed parameters? After all the parameters will most likely be hardcoded in to the website that is communicating with your web applicaton..Type once, type it correct! — Geerten
I want to reject the typo'ed params. If there is a typo in param name, I want to show error message. In order to do it, I want to compare parameters passed by user with the method signature — Maxim Eliseev
The RequestMapping will already reject the typo'ed params..So what's the benefit of comparing? — Geerten
The RequestMapping will IGNORE the typo'ed params. I want to identify them and show an error message. — Maxim Eliseev
If you set required=true, it will reject the typo'ed params, because one of the params will be missing then. — Geerten

storm_buster storm_buster · Accepted Answer · 2012-04-03T17:27:31

you can use HttpServletRequest request as

public List<MetricType> getMetricTypes(    
            @RequestParam(value = "subject", required = false) Long subjectId,
            @RequestParam(value = "area", required = false) Long areaId,
            @RequestParam(value = "onlyImmediateChildren", required = false) Boolean onlyImmediateChildren,   
            @RequestParam(value = "componentGroup", required = false) Long componentGroupId  ,
HttpServletRequest request  
            ) throws Exception

and then get all the request parameters names as

request.getParameterNames()

and use loop in them to do your job as

for ( String parameterName:requestParameterNames){

}

Spring MVC - How to get list of @RequestMethod method parameters (possibly by @RequestParam attribute)

1 Answers