java - Cannot refer to the non-final local variable jSONString defined in an enclosing scope -

i trying pass json string server after 60 seconds. @ moment facing problem when try execute myasynctask thread; jsonstring not accessable @ line new myasynctask().execute(jsonstring); , getting error cannot refer non-final local variable jsonstring defined in enclosing scope

this part of code being called onlocationchanged method in inner class of mainactivity:

string jsonstring = converttojson(plong, plat, formatted); postdata sender = new postdata(); sender.timer(jsonstring); 

postdata class:

public class postdata {     string jsonstring;     handler handler = new handler();      public postdata() {         super();     }      public string getjsonstring() {         return jsonstring;     }      public void setjsonstring(string jsonstring) {         this.jsonstring = jsonstring;     }      public void timer(string jsonstring) {         this.jsonstring = jsonstring;          new thread(new runnable() {             @override             public void run() {                 boolean run = true;                 while (run) {                    handler.postdelayed(new runnable() {                        @override                        public void run() {                            new myasynctask().execute(jsonstring); //how can access variable'jsonstring' here?                        }                    }, 5000);                 }             }         }).start();     }      class myasynctask extends asynctask<string, integer, void> {          @override         protected void doinbackground(string... params) {             system.out.println("the output of : doinbackground " +params[0]);             //the connection code.              return null;         }     } } 

use jsonstring declared in postdata trying access timer method parameter not final :

new myasynctask().execute(postdata.this.jsonstring);