Can't find an example that bind a many to many relationship from a form (Ab

Flow
1

Hello,

I’ve been searching for days but can’t find how to bind two entities with many to many relationship (spring boot, hibernate, vaadin 10). Every example I’ve found is about text fields.

I don’t know how to bind with getters and setters or with other way. Can anyone help me, please?

@Entity
public class Project {

	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	private Long id;
	
	@ManyToMany(cascade = { CascadeType.ALL }, fetch = FetchType.EAGER)
	@JoinTable(name="module_project", joinColumns={@JoinColumn(referencedColumnName="ID")}
									  , inverseJoinColumns={@JoinColumn(referencedColumnName="ID")})	
	private List<Module> modules;

@Entity
public class Module {

	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	private Long id;
	
	@ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL, mappedBy = "modules")
	@Fetch(value = FetchMode.SUBSELECT)
	private List<Project> projects;

@SpringComponent
@Scope("request")
public class ProjectEditorDialog extends AbstractEditorDialog<Project> {
    private ListBox<Module> lbLeft;
	private Button bLeft;
	private Button bRight;
	private ListBox<Module> lbRight;
	private Module tempCabecera;
	private List<Module> listLeftCabeceras = new ArrayList<Module>();
	private List<Module> listRightCabeceras = new ArrayList<Module>();
	---.....-----
	private void createLeftColumn() {
			VerticalLayout leftColumn = new VerticalLayout();
			Label lTitle = new Label("Dimensiones disponibles");
			leftColumn.add(lTitle);

			lbLeft = new ListBox<Module>();
			listLeftCabeceras = moduleRepository.findByUrl("proyectos");
			lbLeft.setItems(listLeftCabeceras);

			lbLeft.setRenderer(new ComponentRenderer<>(item -> {
				Label label = new Label(item.getCabecera().getName());
				label.getStyle().set("propertyName", "value");
				return label;
			}));

			leftColumn.add(lbLeft);
			getHorizontalLayout().add(leftColumn);
		}

		private void createCenterColumn() {
			VerticalLayout centerColumn = new VerticalLayout();
			bRight = new Button(">>");
			bRight.addClickListener(new ComponentEventListener<ClickEvent<Button>>() {
				private static final long serialVersionUID = -7189656556900852946L;

				@Override
				public void onComponentEvent(ClickEvent<Button> event) {
					tempCabecera = lbLeft.getValue();
					if (tempCabecera != null) {
						listLeftCabeceras.remove(tempCabecera);
						listRightCabeceras.add(tempCabecera);

						Collections.sort(listLeftCabeceras, new Comparator<Module>() {
							@Override
							public int compare(Module lCabecera, Module rCabecera) {
								return lCabecera.getName().compareTo(rCabecera.getName());
							}
						});

						lbLeft.setItems(listLeftCabeceras);
						lbRight.setItems(listRightCabeceras);

						checkButtons();
					}
				}
			});
			bLeft = new Button("<<");
			bLeft.addClickListener(new ComponentEventListener<ClickEvent<Button>>() {
				private static final long serialVersionUID = -7189656556900852946L;

				@Override
				public void onComponentEvent(ClickEvent<Button> event) {
					tempCabecera = lbRight.getValue();

					if (tempCabecera != null) {
						listRightCabeceras.remove(tempCabecera);
						listLeftCabeceras.add(tempCabecera);

						lbLeft.setItems(listLeftCabeceras);
						lbRight.setItems(listRightCabeceras);
						checkButtons();
					}
				}
			});

			centerColumn.add(bRight);
			centerColumn.add(bLeft);
			getHorizontalLayout().add(centerColumn);
		}

		private void createRightColumn() {
			VerticalLayout rightColumn = new VerticalLayout();
			Label lTitle = new Label("Dimensiones seleccionadas");
			rightColumn.add(lTitle);
			lbRight = new ListBox<Module>();
			lbRight.setRenderer(new ComponentRenderer<>(item -> {
				Label label = new Label(item.getCabecera().getName());
				label.getStyle().set("propertyName", "value");
				return label;
			}));

			rightColumn.add(lbRight);
			getHorizontalLayout().add(rightColumn);
***** I think here is the place where I have to bind the result, but is not working. This is several test I did *******
			//getBinder().forField(aux).bind(Project::getBudget, Project::setBudget);
			//getBinder().bindInstanceFields(listRightCabeceras);
			//getBinder().getBinding("Project.modules");
			//getBinder().forField(lbRight).bind("Project.modules");
			//getBinder().bindInstanceFields(getBinder().getBean());
			//getBinder().forField(lbRight).bind(List.class);
***** ... *******
		}

		private void checkButtons() {
			if (listRightCabeceras.size() > 0)
				bLeft.setEnabled(true);
			else
				bLeft.setEnabled(false);

			if (listLeftCabeceras.size() > 0)
				bRight.setEnabled(true);
			else
				bRight.setEnabled(false);
		}
	---.................---