spring boot - How to fetch record on the basis of @DBRef in collection in mongodb? -

hi using mongodb springboot , not able fetch records on basis of @dbref. scenerio is:

i have authenticationtoken collection , user collection follows:

{     "_id" : objectid("556bdfc2ccf2e6509f8a2849"),     "_class" : "com.samepinch.domain.user.authenticationtoken",     "token" : "2efd1cfe-2f2f-4163-b500-bac6e4654287",     "createddate" : isodate("2015-06-01t04:29:54.364z"),     "updateddate" : isodate("2015-06-01t04:29:54.364z"),     "user" : dbref("users", objectid("556bdfc2ccf2e6509f8a2848")) } 

and user

{     "_id" : objectid("556bdfc2ccf2e6509f8a2848"),     "_class" : "com.samepinch.domain.user.user",     "age" : 0,     "username" : "abc@yahoo.com",     "roles" : [         "role_user"     ],     "firstname" : "abc",     "lastname" : "mno",     "email" : "abc@yahoo.com",     "gender" : "male",     "isaccountlocked" : false,     "prefagefrom" : 0,     "prefageto" : 0,     "notificationnewmatch" : true,     "notificationmessage" : true,     "createddate" : isodate("2015-06-01t04:29:54.325z"),     "updateddate" : isodate("2015-06-01t04:29:54.325z") } 

now want authentication token on basis of user id in authentication collection.

i using mongo repository fetch authenticationtoken on basis of user id not working.

to fetch authenticationtoken

step 1

public authenticationtoken findbyuserid(string userid){       objectid objid =  new objectid(userid);         return authrepository.findbyuserid(objid);     } 

step 2

public interface authenticationtokenrepository extends mongorepository<authenticationtoken, string> {      authenticationtoken save(authenticationtoken token);      authenticationtoken findbytoken(string token);      @query("{'user._id' : ?0}")     authenticationtoken findbyuserid(objectid objid); } 

i following above steps fetch authenticationtoken db getting null. working fine when not using @dbref on user in authentication domain.

authenticationtoken

public class authenticationtoken extends baseentity{      @jsonproperty     string token;      @dbref     user user;      public authenticationtoken(string token,user user){         this.token = token;         this.user = user;     }      public user getuser() {         return user;     }      public void setuser(user user) {         this.user = user;     }      public string gettoken() {         return token;     }      public void settoken(string token) {         this.token = token;     }    } 

this not big deal,use spring data mongodb criteria

query query = new query(criteria.where("user.$id").is(new objectid(userid)));         authenticationtoken token = mongotemplate.findone(query, authenticationtoken.class);