Javafx主頁面，控制器和數據庫類別運行不正常

Question

我不知道爲什麼主類不能正常工作。我創建了主頁面， 然後，建模（連接數據庫與主應用程序），然後數據庫（從數據庫中檢索信息）。 創建所有內容後，我發現顯示結果的主類不是顯示結果，而是從db中獲取， 顯示的是'Controller @ person ...'（它是包和類的名稱）。

通過代碼後，確定代碼中沒有錯誤，但可能是語法錯誤。 誰能幫我找出什麼在代碼丟失

public class Cbt extends Application { 
    private SchoolDB sdb; 
     Person person = new Person(); 

    TextField username, firstName, lastName, initial, password; 
    GridPane addGridStaffRegLO; 
    AnchorPane staffRegLO; 
    Scene staffReg; 
    ComboBox qualification; 

    public void start(Stage theMainStage) throws DBException { 
     stageCbt = theMainStage; 

     border = new BorderPane(); 

      hbox = addHBox(); 
      border.setTop(addHBox()); 
      border.setBottom(addHDBox()); 
      border.setLeft(addVbox()); 
      border.setRight(addFlowPaneLO()); 
      border.setCenter(addLogReg(addGridPaneLO())); 

    } 

    private HBox addHBox() { 

      hbox = new HBox(); 
      hbox.getStyleClass().add("hbox"); 

      hbox.getChildren().add(displayWelcomeMsg); 

      return hbox; 
    } 

      //the vbox for left border 
     private VBox addVbox() { 
      vbox = new VBox(); 
      vbox.setPadding(new Insets(15, 12, 15, 12)); 
      vbox.setSpacing(10); 

      return vbox; 
    } 

    private HBox addHDBox() { 

      hbdox = new HBox(); 
      hbdox.getStyleClass().add("hbox"); 

      hbdox.getChildren().add(displayWelcomeMsg); 

      return hbdox; 
     } 

     private HBox addSHBox() { 

      hbox = new HBox(); 
      hbox.getStyleClass().add("hbox"); 

     hbox.getChildren().add(displayWelcomeMsg); 

      return hbox; 
     } 


    private GridPane addStaffGridRegLO() { 
     addGridStaffRegLO = new GridPane(); 
     addGridStaffRegLO.getStyleClass().add("grid"); 
     addGridStaffRegLO.setHgap(10); 
     addGridStaffRegLO.setVgap(10); 
     addGridStaffRegLO.setPadding(new Insets(0, 10, 0, 10)); 

     Text welcome = new Text("Welcome to the school CBT for jamb"); 
     welcome.setFont(Font.font("Arial", FontWeight.BOLD, 20)); 
     addGridStaffRegLO.add(welcome, 1, 0); 

     Text ss = new Text("For both staffs and students"); 
     ss.setFont(Font.font("Arial", FontWeight.BOLD, 20)); 
     addGridStaffRegLO.add(ss, 2, 0); 

     firstName = new TextField(); 
     addGridStaffRegLO.add(firstName, 3, 1); 
     firstName.textProperty().bind(person.firstNameProperty()); 
     firstName.setPromptText("Enter your student firstname"); 
     Tooltip fn = new Tooltip(); 
     fn.setText("student firstname here"); 
     firstName.setTooltip(fn); 

     lastName = new TextField(); 
     addGridStaffRegLO.add(lastName, 3, 2); 
     lastName.textProperty().bind(person.lastNameProperty()); 
     lastName.setPromptText("Enter student lastname"); 
     Tooltip ln = new Tooltip(); 
     ln.setText("Student lastname here"); 
     lastName.setTooltip(ln); 

     initial = new TextField(); 
     initial.textProperty().bind(person.initialProperty()); 
     addGridStaffRegLO.add(initial, 3, 3); 
     initial.setPromptText("Staff number here"); 
     Tooltip initTip = new Tooltip(); 
     initTip.setText("Student initial here"); 
     initial.setTooltip(initTip); 

     username = new TextField(); 
     addGridStaffRegLO.add(username, 3, 4); 
     username.textProperty().bind(login.usernameProperty()); 
     username.setPromptText("Enter your username"); 
     Tooltip userTip = new Tooltip(); 
     userTip.setText("your username here"); 
     username.setTooltip(userTip); 

     password = new PasswordField(); 
     addGridStaffRegLO.add(password, 3, 5); 
     password.textProperty().bind(login.passwordProperty()); 
     password.setPromptText("Your password here"); 
     Tooltip pass = new Tooltip(); 
     pass.setText("Your passowrd here"); 
     password.setTooltip(pass); 

    ObservableList<School> options = FXCollections.observableArrayList(); 

    qualification = new ComboBox(options); 
     qualification.setPromptText("Staff qualification here"); 
     addGridStaffRegLO.add(qualification, 3, 6); 

     try { 
      options.addAll(SchoolDB.getAllStudents()); 
     } catch (DBException ex) { 
      Logger.getLogger(Cbt.class.getName()).log(Level.SEVERE, null, ex); 
     } 

    return addGridStaffRegLO; 
    } 

    private AnchorPane addStaffRegLO(GridPane addGridStaffRegLO) { 
     staffRegLO = new AnchorPane(); 
     staffRegLO.getStyleClass().add("pane"); 
     Register = new Button("Signup"); 
     HBox hb = new HBox(); 
     hb.getStyleClass().add("hb"); 
     hb.getChildren().add(Register); 
     staffRegLO.getChildren().addAll(addGridStaffRegLO, hb); 
// Anchor buttons to bottom right, anchor grid to top 
     AnchorPane.setBottomAnchor(hb, 8.0); 
     AnchorPane.setRightAnchor(hb, 5.0); 
     AnchorPane.setTopAnchor(addGridStaffRegLO, 10.0); 
     return staffRegLO; 
    } 
} 

這是模型類

public class Person { 
private final SimpleStringProperty firstName = new SimpleStringProperty(this, "firstName"); 

    public StringProperty firstNameProperty() { 
     return firstName; 
    } 

    public final String getFirstName() { 
     return firstNameProperty().get(); 
    } 

    public void setFirstName(String firstName) { 
     firstNameProperty().set(firstName); 
    } 

    private final SimpleStringProperty lastName = new SimpleStringProperty(this, "lastName"); 
    public StringProperty lastNameProperty() { 
     return lastName; 
    } 

    public final String getLastName() { 
     return lastNameProperty().get(); 
    } 

    public void setLastName(String lastName) { 
     lastNameProperty().set(lastName); 
    } 

    private final SimpleStringProperty initial = new SimpleStringProperty(this, "initial"); 
    public StringProperty initialProperty() { 
     return initial; 
    } 

    public final String getInitial() { 
     return initialProperty().get(); 
    } 

    public void setInitial(String initial) { 
     initialProperty().set(initial); 
    } 

    private final IntegerProperty studentId = new SimpleIntegerProperty(this, "studentId"); 
    public IntegerProperty studentIdProperty() { 
     return studentId; 
    } 

    public final int getStudentId() { 
     return studentIdProperty().get(); 
    } 

    public void setStudentId(int studentId) { 
     studentIdProperty().set(studentId); 
    } 

     public Person() { 

    } 

    public Person(String firstName, String lastName, String initial, int studentId) { 
     setFirstName(firstName); 
     setLastName(lastName);; 
     setInitial(initial); 
     setStudentId(studentId); 

    } 

這是數據庫類

import java.util.ArrayList; 
import java.util.List; 
import java.sql.SQLException; 
import java.sql.PreparedStatement; 
import java.sql.ResultSet; 
import java.sql.*; 

import controller.Person; 


    public class SchoolDB { 
    public static List<School> getAllStudents() throws DBException { 
      String sql = "SELECT last_name, first_name, middle_name, id FROM stu_reg"; 
      List<School> studentsDetail = new ArrayList<>(); 
      Connection connection = DBUtil.getConnection(); 
      try (PreparedStatement ps = connection.prepareStatement(sql); 
        ResultSet rs = ps.executeQuery()) { 
       while (rs.next()) { 
        String lastName = rs.getString("last_name"); 
        String firstName = rs.getString("first_name"); 
        String initial = rs.getString("middle_name"); 
        int studentId = rs.getInt("id"); 

        //Person p = new Person(lastName, firstName, initial, studentId); 
        School sch = new School(); 
        sch.setFirstName(firstName); 

        studentsDetail.add(sch); 
       } 
       return studentsDetail; 
      } catch (SQLException e) { 
       throw new DBException(e); 
      } 
     } 

    } 

Answer 1

你不不使用在主頁面中正確控制類