首页 > 解决方案 > 将文本字段数据从一个类移动到另一个/问题时将其加载到数据库中

问题描述

我正在尝试获取用于登录我的应用程序的用户名的数据,以便在创建约会时将其插入数据库,这样我就可以使用该用户名显示该用户登录的所有约会应用程序。

这是“Programaritest”表

ID_programare | Nume | Prenume | Data | Ora | Departament | Doctor | Username | Nr_telefon

这是用户名保存为唯一的帐户表

ID_account | Username | Password | Email | Nume |  Prenume | Admin

这是使用用户名的地方:

package LicentaApp;



public class LogareController implements Initializable {
 public LoginVerifier loginVerifier = new LoginVerifier();







   @FXML
   private TextField Numeutilzator; Numeutilziator is the username that I am talking about

   @FXML
   private PasswordField Parola;

   @FXML
   private Label Stare;









 @Override
 public void initialize(URL location, ResourceBundle resources) {


  if (loginVerifier.Conexiune()) {
      Stare.setText("");
  } else {

      Stare.setText("Conexiune nereusita!");

  }

 }

 public void Autentificare (ActionEvent event) {
 try {
         if(loginVerifier.testaredate(Numeutilzator.getText(),     Parola.getText())) {
         Stare.setText("Autentificare reusita !");
         ((Node)event.getSource()).getScene().getWindow().hide();
            Stage StagePrincipala= new Stage();
            FXMLLoader incarcator= new FXMLLoader();
            Pane parinte = incarcator.load(getClass().getResource("/LicentaApp/Meniu.fxml").openStream());

            Scene scene = new Scene(parinte);
                scene.getStylesheets().add(getClass().getResource("Style1212.css").toExternalForm());
            StagePrincipala.setScene(scene);
            StagePrincipala.show();

          }
     else { 
         Stare.setText("Nume de utilizator sau parola incorect");

     }




} catch (SQLException e) {





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

    e.printStackTrace();
    }
 }
 @FXML
    public void Inregistrare(ActionEvent event) {
        try {
         ((Node)event.getSource()).getScene().getWindow().hide();
            Stage PS= new Stage();
            FXMLLoader incarcator= new FXMLLoader();
            Pane parinte = incarcator.load(getClass().getResource("/LicentaApp/InregistrareUser.fxml").openStream());
            Scene scena = new Scene(parinte);
            scena.getStylesheets().add(getClass().getResource("Style1212.css").toExternalForm());
            PS.setScene(scena);
            PS.show();
    } catch (Exception e) {

    }

*Here I m calling the function that I made in AddProgramareController and 
passing it the username located in Numeutilzator*

@FXML 
 public void GetUsername() {
     try {
     FXMLLoader loader=new     FXMLLoader(getClass().getResource("/LicentaApp/AddProgramare.fxml"));
     Parent root = (Parent) loader.load();

     AddProgramareController AddPr=loader.getController();
     AddPr.MyUsername(Numeutilzator.getText());


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

}
}
     ***THis is where I save the username so I can use it to add it into the     db***  

在这里,我尝试添加一个预约,以及我通过 FXML 获得的数据,我也尝试将用户名添加到表中

package LicentaApp;



public class AddProgramareController implements Initializable {
    ObservableList Timestamp=FXCollections.observableArrayList();




@FXML
private TextField Nume;

@FXML
private TextField Prenume;

@FXML
private TextField Ora;

@FXML
private DatePicker Data;

@FXML
private TextField Departament;

@FXML
private TextField Doctor;

@FXML
private TextField Nr_telefon;

@FXML
private TextField Numeutilizator;













public void initialize(URL location, ResourceBundle resources) {

} 

*Here's the function that I'll call in GetUsername from LogareController
 public void MyUsername(String Numeutilizator) {
    this.Numeutilizator.setText(Numeutilizator);

}

@FXML 
private void AddProgramare(ActionEvent event) throws SQLException, IOException  {


    String Interogare1= "INSERT INTO programaritest(Nume,Prenume,Data,Ora,Departament,Doctor,Nr_telefon,Numeutilizator) VALUES(?,?,?,?,?,?,?,?)";

    String nume=Nume.getText();
    String prenume=Prenume.getText();

    LocalDate data=Data.getValue(); 

    String ora=Ora.getText();
    String departament=Departament.getText();
    String doctor=Doctor.getText();
    String nr_telefon=Nr_telefon.getText();
    String numeutilizator=Numeutilizator.getText();

    try {
        ConectaredB ConectaredB=new ConectaredB();
        Connection conexiune=ConectaredB.logareDB();
        PreparedStatement MG = conexiune.prepareStatement(Interogare1);


        MG.setString(1, nume);
        MG.setString(2, prenume);
        MG.setDate(3, Date.valueOf(data)); 
        MG.setString(4, ora);
        MG.setString(5, departament);
        MG.setString(6, doctor);
        MG.setString(7, nr_telefon);
        MG.setString(8, numeutilizator);

        MG.executeUpdate();

        // ...
   } catch (SQLException exceptie1) {
       exceptie1.printStackTrace(); 
   }


}
}

尝试添加新约会时收到的错误消息是:

原因:LicentaApp.AddProgramareController.AddProgramare(AddProgramareController.java:103) 处的 java.lang.NullPointerException

在第 103 行: String numeutilizator=Numeutilizator.getText();

因此,由于某种原因,它似乎仍然没有加载用户名。

所以基本上要么我让用户名将其插入数据库的方式是错误的,要么实际插入是错误的。

标签: javamysqlsqljavafx

解决方案


该错误似乎在您getText methodclass LogareController.

您有以下内容:

public String getText() {
    TextField Numeutilizator = new TextField();
    Numeutilizator.getText();
    return null;
}

您总是返回 null 而不是文本字段中的文本。您还将Numeutilizator在始终为空的方法中本地重新创建变量。您应该改用您在课程开始时定义的那个。我相信将getText方法更改为以下应该可以解决您的错误:

public String getText() {
    return this.Numeutilizator.getText();
}

希望有帮助。


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