Java, скачивание фаила

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Порядок чтения/изучения:

• Работа с сетью

• Построение пользовательских интерфейсов:

  import javafx.application.Application;
  import javafx.scene.Scene;
  import javafx.scene.control.Alert;
  import javafx.scene.control.Button;
  import javafx.scene.control.TextField;
  import javafx.scene.layout.BorderPane;
  import javafx.scene.layout.VBox;
  import javafx.stage.FileChooser;
  import javafx.stage.Stage;
  import java.io.BufferedInputStream;
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.net.HttpURLConnection;
  import java.net.URL;
  
  public class Downloader extends Application {
      @Override
      public void start(Stage primaryStage) throws Exception {
          TextField textFieldLink = new TextField();
          textFieldLink.setPromptText("Ссылка");
          textFieldLink.setText("https://github.com/google/guava/archive/master.zip");
          BorderPane borderPaneSelect = new BorderPane();
          TextField textFieldFile = new TextField();
          textFieldFile.setText(System.getProperty("user.home") + "/master.zip");
          textFieldFile.setPromptText("Файл для сохранения");
          Button buttonSelectFile = new Button("Выберите файл для сохранения");
          buttonSelectFile.setOnAction(event -> {
              FileChooser fileChooser = new FileChooser();
              File file = fileChooser.showSaveDialog(primaryStage);
              if (file != null) {
                  textFieldFile.setText(file.getAbsolutePath());
              }
          });
          borderPaneSelect.setCenter(textFieldFile);
          borderPaneSelect.setRight(buttonSelectFile);
          VBox vBox = new VBox(textFieldLink, borderPaneSelect);
          Button buttonLoad = new Button("Загрузить");
          buttonLoad.setOnAction(event -> {
              try {
                  HttpURLConnection httpURLConnection = (HttpURLConnection) new URL(textFieldLink.getText()).openConnection();
                  try (BufferedInputStream bufferedInputStream = new BufferedInputStream(httpURLConnection.getInputStream());) {
                      try (FileOutputStream fileOutputStream = new FileOutputStream(textFieldFile.getText())) {
                          int data;
                          while ((data = bufferedInputStream.read()) != -1) {
                              fileOutputStream.write(data);
                          }
                          Alert alert = new Alert(Alert.AlertType.INFORMATION);
                          alert.setContentText("Файл загружен");
                          alert.show();
                      }
                  }
              } catch (IOException e) {
                  e.printStackTrace();
              }
          });
          BorderPane borderPaneLoad = new BorderPane();
          borderPaneLoad.setBottom(buttonLoad);
          BorderPane borderPaneCommon = new BorderPane();
          borderPaneCommon.setCenter(vBox);
          borderPaneCommon.setBottom(borderPaneLoad);
          Scene scene = new Scene(borderPaneCommon);
          primaryStage.setTitle("Загрузка файла");
          primaryStage.setScene(scene);
          primaryStage.setWidth(800);
          primaryStage.show();
      }
  }