Vaadin Projekt Funkioniert nicht...

[Koloso]

Hey, ich habe eine kleine Website geschrieben, mir ist jedoch anscheinend ein Fehler unterlaufen, den ich nicht auffinden kann. Könnte einer von euch rüber sehen? Die Fehlermeldung lautet:
type Status report

message /YoutubeProjekt/

description The requested resource is not available.

MyUI.java

/*
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* and open the template in the editor.
*/
package com.vandelisim.youtubeprojekt;

import com.vaadin.annotations.Theme;
import com.vaadin.data.fieldgroup.BeanFieldGroup;
import com.vaadin.data.util.BeanItemContainer;
import com.vaadin.server.VaadinRequest;
import com.vaadin.spring.annotation.SpringUI;
import com.vaadin.ui.Button;
import com.vaadin.ui.Grid;
import com.vaadin.ui.TextField;
import com.vaadin.ui.UI;
import com.vaadin.ui.VerticalLayout;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;

/**
*
* @author Leon
*/
@SpringUI
@Theme("valo")
public class MyUI extends UI {
   
    @Autowired
    private CustomerService service;

    private Customer customer;

    private Grid grid = new Grid();
    private TextField firstName = new TextField("First name");
    private TextField lastName = new TextField("Last name");
    private Button save = new Button("Save", e -> saveCustomer());

    @Override
    protected void init(VaadinRequest request) {
        updateGrid();
        grid.setColumns("firstName", "lastName");
        grid.addSelectionListener(e -> updateForm());

        VerticalLayout layout = new VerticalLayout(grid, firstName, lastName,
                save);
        layout.setMargin(true);
        layout.setSpacing(true);
        setContent(layout);
    }

    private void updateGrid() {
        List customers = service.findAll();
        grid.setContainerDataSource(new BeanItemContainer<>(Customer.class,
                customers));
        setFormVisible(false);
    }

    private void updateForm() {
        if (grid.getSelectedRows().isEmpty()) {
            setFormVisible(false);
        } else {
            customer = (Customer) grid.getSelectedRow();
            BeanFieldGroup.bindFieldsUnbuffered(customer, this);
            setFormVisible(true);
        }
    }

    private void setFormVisible(boolean visible) {
        firstName.setVisible(visible);
        lastName.setVisible(visible);
        save.setVisible(visible);
    }

    private void saveCustomer() {
        service.update(customer);
        updateGrid();
    }
}

Customer:

/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package com.vandelisim.youtubeprojekt;

/**
*
* @author Leon
*/
public class Customer {
    private Long id;
    private String firstName, lastName;

    public Customer(Long id, String firstName, String lastName) {
        this.id = id;
        this.firstName = firstName;
        this.lastName = lastName;
    }

    public String getFirstName() {
        return firstName;
    }

    public Long getId() {
        return id;
    }

    public String getLastName() {
        return lastName;
    }
}

CustomerService:

/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package com.vandelisim.youtubeprojekt;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Component;

import java.util.List;

@Component
public class CustomerService {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    public List findAll() {
        return jdbcTemplate.query(
            "SELECT id, first_name, last_name FROM customers",
                (rs, rowNum) -> new Customer(rs.getLong("id"),
                rs.getString("first_name"), rs.getString("last_name")));
    }

    public void update(Customer customer) {
        jdbcTemplate.update(
            "UPDATE customers SET first_name=?, last_name=? WHERE id=?",
            customer.getFirstName(), customer.getLastName(), customer.getId());
    }

}

Danke jetzt schon einmal.

 

[Joose]

Hast du schon mal die Logfiles durchgeschaut?
Nicht nur die der Anwendung sondern auch vom Server auf dem das Vaadin Projekt läuft.

Ich nehme an beim Starten gab es einen Fehler, welcher in den Logs verzeichnet sein müsste.