i am trying to show my sql table data to my grid but nothing seems to work.
can you point me where i was wrong?
i found in the internet so many ways but none as worked for me.
hope you can find the problem and assist me.
Using: Vaddin 14 with Spring boot
CustomerService.java
@Component
public class CustomerService {
@Autowired
private JdbcTemplate jdbcTemplate;
public List<Customer> findAll() {
return jdbcTemplate.query(
"SELECT ID, FirstName, LastName FROM customer",
(rs, rowNum) -> new Customer(rs.getLong("id"),
rs.getString("First Name"), rs.getString("Last Name")));
}
public void update(Customer customer) {
jdbcTemplate.update("INSERT INTO customer (FirstName,LastName) VALUES(?,?)",customer.getFirstName(),customer.getLastName());
}
}
MainView.Java
public class MainView extends VerticalLayout {
@Autowired
private CustomerService service ;
public Customer customer = new Customer();
private Binder<Customer> binder = new Binder<>(Customer.class);
private TextField firstName = new TextField("First name");
private TextField lastName = new TextField("Last name");
private Grid<Customer> grid = new Grid(Customer.class);
private Button save = new Button("Save", e -> {
try {
binder.writeBean(customer);
saveCustomer();
binder.readBean(new Customer());
} catch (ValidationException ex) {
ex.printStackTrace();
}
});
public MainView(CustomerService service) {
add(
new H1("הוסף לקוח"),
buildForm(),
grid
);
updateGrid(); // update the grid with the sql data
setSizeFull();
}
private void saveCustomer() throws ValidationException {
service.update(customer);
}
private Component buildForm() {
// TextField id = new TextField("ID");
TextField firstName = new TextField("First name");
TextField lastName = new TextField("Last name");
Div errorsLayout = new Div();
binder.forField(firstName)
.bind(
Customer::getFirstName,Customer::setFirstName
);
binder.forField(lastName)
.bind(
Customer::getLastName,Customer::setLastName
);
Button reload = new Button("reload", e ->{
try{
binder.readBean(customer);
} catch (Exception ex) {
ex.printStackTrace();
}
});
// Configure UI components
save.setThemeName("primary");
// Wrap components in layouts
HorizontalLayout formLayout = new HorizontalLayout(grid,firstName,lastName,save,reload);
Div wrapperLayout = new Div(formLayout, errorsLayout);
formLayout.setDefaultVerticalComponentAlignment(Alignment.BASELINE);
wrapperLayout.setWidth("100%");
grid.setColumnReorderingAllowed(true);
return wrapperLayout;
}
private void updateGrid() {
List<Customer> customers = service.findAll();
grid.setItems(customers);
}
The error i gets:
There was an exception while trying to navigate to '' with the exception message 'Error creating bean with name 'com.packagename.myapp.spring.MainView': Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.packagename.myapp.spring.MainView]
: Constructor threw exception; nested exception is java.lang.NullPointerException'