java - Null Pointer Exception in FXML -

so have 1 controller class looks this. isn't whole thing, important part.

in handle button action method, i'm trying input text fields in 1 scene , transfer string , set them on label in scene.

i have code

public class fxmldocumentcontroller implements initializable {      @fxml     private radiobutton newcustomer;      @fxml     private radiobutton regularcustomer;      @fxml     private label total;      @fxml     private textfield nameinput;      @fxml     private textfield phonenumberinput;      @fxml     private textfield emailinput;      @fxml     private textfield addressinput;      @fxml     private checkbox brakes;      @fxml     private checkbox tirerotation;      @fxml     private checkbox fluidcheck;      @fxml     private checkbox carwash;      @fxml     private checkbox inspection;      @fxml     private checkbox tirereplacement;      @fxml     private checkbox oilchange;      @fxml     private combobox<string> tirechoices;      @fxml     private combobox<string> oilchoices;      @fxml     private void handlebuttonaction(actionevent event){           try{             stage stage = new stage();             fxmlloader loader = new fxmlloader();             pane root = loader.load(getclass().getresource("invoicewindow.fxml").openstream());             invoicewindowcontroller invoice = (invoicewindowcontroller) loader.getcontroller();             invoice.printcustomerinfo(nameinput.gettext(),phonenumberinput.gettext(),emailinput.gettext(),addressinput.gettext());             scene scene = new scene(root);             stage.setscene(scene);             stage.show();         }catch(exception e){      } } 

and second controller class code looks this

public class invoicewindowcontroller implements initializable {      @fxml     private label name;      @fxml     private label phonenumber;      @fxml     private label email;      @fxml     private label address;      @override     public void initialize(url url, resourcebundle rb) {      }           public void printcustomerinfo(string name, string number, string email, string address){         this.name.settext(name);         this.phonenumber.settext(number);         this.email.settext(email);         this.address.settext(address);     } } 

i'm receiving null pointer exception at:

invoice.printcustomerinfo(nameinput.gettext(),phonenumberinput.gettext(),emailinput.gettext(),addressinput.gettext()); 

i assure fx:id correctly assigned.

i checked thousand times. i'm losing mind.