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Spring MVC - How to get all request params in a map in Spring controller?

Sample URL:

../search/?attr1=value1&attr2=value2&attr4=value4

I do not know the names of attr1, att2, and attr4.

I would like to be able to do something like that (or similar, don't care, just as long as I have access to the Map of request param name -> value:

@RequestMapping(value = "/search/{parameters}", method = RequestMethod.GET)
public void search(HttpServletRequest request, 
@PathVariable Map<String,String> allRequestParams, ModelMap model)
throws Exception {//TODO: implement}

How can I achieve this with Spring MVC?


A
Adam Gent

While the other answers are correct it certainly is not the "Spring way" to use the HttpServletRequest object directly. The answer is actually quite simple and what you would expect if you're familiar with Spring MVC.

@RequestMapping(value = {"/search/", "/search"}, method = RequestMethod.GET)
public String search(
@RequestParam Map<String,String> allRequestParams, ModelMap model) {
   return "viewName";
}

If you are looking to process list values, like from a group of checkboxes with the same name, use: @RequestParam MultiValueMap<String, String>
Thanks for this. You can do the same thing with headers as well: stackoverflow.com/a/19556291/2599745
This is only working when the request method is GET or POST. It is not working for PUT, DELETE etc request methods.
Don't forget to add import org.springframework.ui.ModelMap; as well.
@typelogic ModelMap isn't needed to get all request params as map; that's simply a detail specific to OP's code.
C
Community

Edit

It has been pointed out that there exists (at least as of 3.0) a pure Spring MVC mechanism by which one could get this data. I will not detail it here, as it is the answer of another user. See @AdamGent's answer for details, and don't forget to upvote it.

In the Spring 3.2 documentation this mechanism is mentioned on both the RequestMapping JavaDoc page and the RequestParam JavaDoc page, but prior, it is only mentioned in the RequestMapping page. In 2.5 documentation there is no mention of this mechanism.

This is likely the preferred approach for most developers as it removes (at least this) binding to the HttpServletRequest object defined by the servlet-api jar.

/Edit

You should have access to the requests query string via request.getQueryString().

In addition to getQueryString, the query parameters can also be retrieved from request.getParameterMap() as a Map.


I suspect someone downvoted this answer just because getQueryString returns a String and not a Map. The op was looking for a Map of parameters. I added getParameterMap to your answer to help make it more correct :) +1
No I downvoted because its not the Spring MVC way to do it. @RequestParam will gladly take a Map as a parameter (see my answer).
@AdamGent The question was asked at a time when Spring 3.2 was not yet released. Go back and take a look at the JavaDoc for 3.1, and you will notice there is no such mention of utilizing @RequestParam on a Map<String,String> to retrieve all query string parameters. And please, don't feel so abhorred over the answers you see here...they aren't that bad :) static.springsource.org/spring/docs/3.1.x/javadoc-api/org/…
I think it existed in 3.1 but was not JavaDoced. I didn't say I was abhorred but shocked that the @RequestParam Map<> way was not done. I have slight annoyance in that many modern projects I have seen Spring MVC (spring 3.1 and greater) they will put the HttpServletRequest and HttpServletResponse on every method. And it seems its because junior developers use StackOverflow and google instead of looking at the doc. This makes it difficult for the Spring project to switch from servlet api to say a Netty API. JAX-RS has similar issues of abuse but at a far lesser degree.
And it is JavaDoced in 3.1 just not in all the right places: "Additionally, @RequestParam can be used on a Map<String, String> or MultiValueMap<String, String> method parameter to gain access to all request parameters.". Infact it goes all the way back to version 3.0 (I knew I used it before 3.1). My annoyance still stands in that people didn't bother doing the research :)
ℛɑƒæĿᴿᴹᴿ

Here's a simple example of getting requestParams in a Map:

@RequestMapping(value="submitForm.html", method=RequestMethod.POST)
public ModelAndView submitForm(@RequestParam Map<String, String> reqParam) {
    String name  = reqParam.get("studentName");
    String email = reqParam.get("studentEmail");     
    ModelAndView model = new ModelAndView("AdmissionSuccess");
    model.addObject("msg", "Details submitted by you::Name: " + name
                                                + ", Email: " + email );
}

In this case, it will bind the values:

studentName with name

studentEmail with email


I really like this answer but Map seems to have a problem because it is possible that some parameters have multiple values. I guess Map or so makes more sense.
j
jmort253

The HttpServletRequest object provides a map of parameters already. See request.getParameterMap() for more details.


Get parameter map will also contain form data from a POST request. If the user does not know the keys in the query string, then how will they be able to distinguish between what came from the query string and what is from data from a POST body?
Are you telling me you're going to process a form post but you have no idea what the actual form parameters are?
The question states that he doesn't know what the parameter names are. Also, I do not know what they are either. ;)
Sorry I find the premise a bit ridiculous.
It makes sense in a data driven application. One where request paths and query strings can be made up by the client, and the application server would then look up the corresponding value (from any sort of datasource) by using these paths and query strings as keys.
B
Biggy_java

you can simply use this:

Map<String, String[]> parameters = request.getParameterMap();

That should work fine


A
Aniket Kulkarni

Use org.springframework.web.context.request.WebRequest as a parameter in your controller method, it provides the method getParameterMap(), the advantage is that you do not tight your application to the Servlet API, the WebRequest is a example of JavaEE pattern Context Object.


A
Aniket Kulkarni

There are two interfaces

org.springframework.web.context.request.WebRequest org.springframework.web.context.request.NativeWebRequest

Allows for generic request parameter access as well as request/session attribute access, without ties to the native Servlet/Portlet API.

Ex.:

@RequestMapping(value = "/", method = GET)
public List<T> getAll(WebRequest webRequest){
    Map<String, String[]> params = webRequest.getParameterMap();
    //...
}

P.S. There are Docs about arguments which can be used as Controller params.


Thank you it works. May I ask, what's the point of String[] as the value? I have to index it to 0 just to get the value.
There can be an array of values like key=val1,val2 or key=val1&key=val2 (if I remember correctly spring support both of these notations) so you will get array with 2 elements
b
buræquete

I might be late to the party, but as per my understanding , you're looking for something like this :

for(String params : Collections.list(httpServletRequest.getParameterNames())) {
    // Whatever you want to do with your map
    // Key : params
    // Value : httpServletRequest.getParameter(params)                
}

K
Krzysztof Atłasik
@SuppressWarnings("unchecked")
Map<String,String[]> requestMapper=request.getParameterMap();
JsonObject jsonObject=new JsonObject();
for(String key:requestMapper.keySet()){
    jsonObject.addProperty(key, requestMapper.get(key)[0]);
}

All params will be stored in jsonObject.


y
yuranos

There is fundamental difference between query parameters and path parameters. It goes like this: www.your_domain?queryparam1=1&queryparam2=2 - query parameters. www.your_domain/path_param1/entity/path_param2 - path parameters.

What I found surprising is that in Spring MVC world a lot of people confuse one for the other. While query parameters are more like criteria for a search, path params will most likely uniquely identify a resource. Having said that, it doesn't mean that you can't have multiple path parameters in your URI, because the resource structure can be nested. For example, let's say you need a specific car resource of a specific person:

www.my_site/customer/15/car/2 - looking for a second car of a 15th customer.

What would be a usecase to put all path parameters into a map? Path parameters don't have a "key" when you look at a URI itself, those keys inside the map would be taken from your @Mapping annotation, for example:

@GetMapping("/booking/{param1}/{param2}")

From HTTP/REST perspective path parameters can't be projected onto a map really. It's all about Spring's flexibility and their desire to accommodate any developers whim, in my opinion.

I would never use a map for path parameters, but it can be quite useful for query parameters.