package sample;


import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;

import java.io.IOException;

public class Main extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception {
        try {
            Parent root = FXMLLoader.load(getClass().getResource("sample.fxml"));
            primaryStage.setTitle("Hello World");
            primaryStage.setScene(new Scene(root));
            primaryStage.show();

        }
        catch (IOException e) {
            e.printStackTrace();
        }
    }



    public static void main(String[] args) {
        launch(args);
    }
}
package sample;

import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.stage.Stage;

import java.io.IOException;

public class Controller {

    private String c;
    private String d;
    private int b=0;

    @FXML
    private TextField zakres;

    @FXML
    private TextField args;

    @FXML
    private Label label;

    @FXML
    void akcja() {
        try {
            c = zakres.getText();
            d = args.getText();
            int a = Integer.parseInt(c);
            b = Integer.parseInt(d);
            try {
                Parent root1 = FXMLLoader.load(getClass().getResource("sample2.fxml"));
                Stage stage = new Stage();
                stage.setTitle("My New Stage Title");
                stage.setScene(new Scene(root1));
                stage.show();
                label.setText("Dane: " + c + "\t" + d);

            } catch (IOException e) {
                e.printStackTrace();
            }
        } catch (NumberFormatException e) {
            label.setText("Nieprawidłowe dane: " + c + "\t" + d);
        }

    }

    @FXML
    private TextField args2;
    @FXML
    private Label wyniki;
    @FXML
    private Button ok;
    @FXML
    private Label kom;

    @FXML
    public void akcja2() throws Exception {


        try {
            String parameters = args2.getText();
            String[] parameterpParts = parameters.split(" ");
            System.out.println();

            if (parameterpParts.length != b){   //////////////////////////  <<<<<<<<<<<<<< HERE
                kom.setText("Swietnie");
            } else throw new Exception();
        } catch (Exception a) {
            kom.setText("Nieprawidlowa ilosc argumentow");
        }
    }
}




<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>

<?import javafx.scene.layout.Pane?>
<?import javafx.scene.control.TextField?>
<Pane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/9.0.1" xmlns:fx="http://javafx.com/fxml/1" fx:controller="sample.Controller">
    <children>
        <Label layoutX="147.0" layoutY="180.0" text="Podaj zakres:" />
        <Label layoutX="147.0" layoutY="259.0" text="Podai ilosc argumentow:" />
        <TextField fx:id="zakres" layoutX="324.0" layoutY="176.0" />
        <TextField fx:id="args" layoutX="324.0" layoutY="255.0" />
        <Button fx:id="przycisk" layoutX="473.0" layoutY="333.0" mnemonicParsing="false" onAction="#akcja" text="Button" />
        <Label fx:id="label" layoutX="80.0" layoutY="307.0" prefHeight="62.0" prefWidth="382.0" />
    </children>
</Pane>
<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<Pane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/9.0.1" xmlns:fx="http://javafx.com/fxml/1" fx:controller="sample.Controller">
    <children>
        <Label layoutX="134.0" layoutY="160.0" text="Dane: " />
        <TextField fx:id="args2" layoutX="300.0" layoutY="156.0" />
        <Label fx:id="wyniki" layoutX="134.0" layoutY="200.0" prefHeight="117.0" prefWidth="314.0" text="Wyniki: " />
        <Button fx:id="ok" layoutX="475.0" layoutY="317.0" mnemonicParsing="false" onAction="#akcja2" text="ok" />
        <Label fx:id="kom" layoutX="55.0" layoutY="321.0" prefHeight="17.0" prefWidth="345.0" />
    </children>
</Pane>