JavaFX MySQL-anslutningsexempel tack

Som minimum behöver du tre klasser:en för att representera dina data, en för ditt användargränssnitt och en för att hantera databasanslutningen. I en riktig app skulle du naturligtvis behöva mer än så här. Det här exemplet följer samma grundläggande exempel som TableView handledning

Anta att din databas har en person tabell med tre kolumner, first_name , last_name , email_address .

Sedan skulle du skriva en Person klass:

import javafx.beans.property.StringProperty ;
import javafx.beans.property.SimpleStringProperty ;

public class Person {
    private final StringProperty firstName = new SimpleStringProperty(this, "firstName");
    public StringProperty firstNameProperty() {
        return firstName ;
    }
    public final String getFirstName() {
        return firstNameProperty().get();
    }
    public final void setFirstName(String firstName) {
        firstNameProperty().set(firstName);
    }

    private final StringProperty lastName = new SimpleStringProperty(this, "lastName");
    public StringProperty lastNameProperty() {
        return lastName ;
    }
    public final String getLastName() {
        return lastNameProperty().get();
    }
    public final void setLastName(String lastName) {
        lastNameProperty().set(lastName);
    }

    private final StringProperty email = new SimpleStringProperty(this, "email");
    public StringProperty emailProperty() {
        return email ;
    }
    public final String getEmail() {
        return emailProperty().get();
    }
    public final void setEmail(String email) {
        emailProperty().set(email);
    }

    public Person() {}

    public Person(String firstName, String lastName, String email) {
        setFirstName(firstName);
        setLastName(lastName);
        setEmail(email);
    }

}

En klass för att komma åt data från databasen:

import java.sql.Connection ;
import java.sql.DriverManager ;
import java.sql.SQLException ;
import java.sql.Statement ;
import java.sql.ResultSet ;

import java.util.List ;
import java.util.ArrayList ;

public class PersonDataAccessor {

    // in real life, use a connection pool....
    private Connection connection ;

    public PersonDataAccessor(String driverClassName, String dbURL, String user, String password) throws SQLException, ClassNotFoundException {
        Class.forName(driverClassName);
        connection = DriverManager.getConnection(dbURL, user, password);
    }

    public void shutdown() throws SQLException {
        if (connection != null) {
            connection.close();
        }
    }

    public List<Person> getPersonList() throws SQLException {
        try (
            Statement stmnt = connection.createStatement();
            ResultSet rs = stmnt.executeQuery("select * from person");
        ){
            List<Person> personList = new ArrayList<>();
            while (rs.next()) {
                String firstName = rs.getString("first_name");
                String lastName = rs.getString("last_name");
                String email = rs.getString("email_address");
                Person person = new Person(firstName, lastName, email);
                personList.add(person);
            }
            return personList ;
        } 
    }

    // other methods, eg. addPerson(...) etc
}

Och sedan en UI-klass:

import javafx.application.Application ;
import javafx.scene.control.TableView ;
import javafx.scene.control.TableColumn ;
import javafx.scene.control.cell.PropertyValueFactory ;
import javafx.scene.layout.BorderPane ;
import javafx.scene.Scene ;
import javafx.stage.Stage ;

public class PersonTableApp extends Application {
    private PersonDataAccessor dataAccessor ;

    @Override
    public void start(Stage primaryStage) throws Exception {
        dataAccessor = new PersonDataAccessor(...); // provide driverName, dbURL, user, password...

        TableView<Person> personTable = new TableView<>();
        TableColumn<Person, String> firstNameCol = new TableColumn<>("First Name");
        firstNameCol.setCellValueFactory(new PropertyValueFactory<>("firstName"));
        TableColumn<Person, String> lastNameCol = new TableColumn<>("Last Name");
        lastNameCol.setCellValueFactory(new PropertyValueFactory<>("lastName"));
        TableColumn<Person, String> emailCol = new TableColumn<>("Email");
        emailCol.setCellValueFactory(new PropertyValueFactory<>("email"));

        personTable.getColumns().addAll(firstNameCol, lastNameCol, emailCol);

        personTable.getItems().addAll(dataAccessor.getPersonList());

        BorderPane root = new BorderPane();
        root.setCenter(personTable);
        Scene scene = new Scene(root, 600, 400);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    @Override
    public void stop() throws Exception {
        if (dataAccessor != null) {
            dataAccessor.shutdown();
        }
    }

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

(Jag skrev bara in det utan att testa, så det kan finnas stavfel, saknade importer, etc, men det borde räcka för att ge dig idén.)