Question

Made a post earlier about this topic (Display values in drill-down SelectOneMenus). The problem that have is not connected to the Object converters as I first thought.

I have two selectOneMenu depending on each other, Sector -> Category. When I persist the background business object that holds a Sector and Category, everything works as expected. Even after the current user session terminates and the user log on again and edit the previous saved business object.

The problem occur when and the entity manager flushes the objects and user wants to display the Sector, Category again from the database. The Sector selectOneMenu displays its value as it should, but the Category selectOneMenu value is not displayed. Although the backing bean has the correct value from the database.

What makes the selectOneMenuto not display certain persisted values/objects when they are loaded from database instead from in-memory?

Edit.xhtml

<h:outputLabel value="Sector:" />
<h:selectOneMenu id="sectorSelector" value="#{activityController.selected.category.sector}" title="#{bundle.CreateSectorLabel_sectorName}" valueChangeListener="#{activityController.changeSectorMenu}" immediate="true">
            <a4j:ajax event="change" execute="@this categoryMenu" render="categoryMenu"/>
            <f:selectItems value="#{sectorController.itemsAvailableSelectOne}"/>
</h:selectOneMenu>

<h:outputLabel value="Category:" />
    <h:selectOneMenu id="categoryMenu" value="#{activityController.selected.category}" title="#{bundle.CreateSectorLabel_sectorName}" 
        binding="#{activityController.categoryMenu}"
            required="true" requiredMessage="#{bundle.CreateCategoryRequiredMessage_sector}">                        
    <f:selectItems value="#{activityController.categorySelection}"/>
</h:selectOneMenu>

Controller bean for Category

@ManagedBean(name = "categoryController")
@SessionScoped
public class CategoryController implements Serializable{

    ....

    @FacesConverter(forClass = Category.class)
    public static class CategoryControllerConverter implements Converter {

        @Override
        public Object getAsObject(FacesContext facesContext, UIComponent component, String value) {
            if (value == null || value.length() == 0) {
                return null;
            }
            CategoryController controller = (CategoryController) facesContext.getApplication().getELResolver().
                    getValue(facesContext.getELContext(), null, "categoryController");
            return controller.ejbFacade.find(getKey(value));
        }

        java.lang.Integer getKey(String value) {
            java.lang.Integer key;
            key = Integer.valueOf(value);
            return key;
        }

        String getStringKey(java.lang.Integer value) {
            StringBuffer sb = new StringBuffer();
            sb.append(value);
            return sb.toString();
        }

        @Override
        public String getAsString(FacesContext facesContext, UIComponent component, Object object) {
            if (object == null) {
                return null;
            }
            if (object instanceof Category) {
                Category o = (Category) object;
                return getStringKey(o.getIdCategory());
            }
            else {
                throw new IllegalArgumentException("object " + object + " is of type " + object.getClass().getName() + "; expected type: " + CategoryController.class.getName());
            }
        }
    }

Part of POJO object

...
public class Category implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "idCategory")
    private Integer idCategory;
    ...

    @Override
    public boolean equals(Object object) {
        if (!(object instanceof Category)) {
            return false;
        }
        Category other = (Category) object;
        if ((this.idCategory == null && other.idCategory != null) || (this.idCategory != null && !this.idCategory.equals(other.idCategory))) {
            return false;
        }
        return true;
}

Functon for creating the SelectItem[] array

public static SelectItem[] getSelectItems(List<?> entities, boolean selectOne) {

        int size = entities.size();
        SelectItem[] items;
        int i = 0;
        if (selectOne) {
            items = new SelectItem[size + 1];
            items[0] = new SelectItem("", ResourceBundle.getBundle("/resources/Bundle").getString("Select_item"));
            i++;
        } else {
            items = new SelectItem[size];
        }

        for (Object x : entities) {
            items[i++] = new SelectItem(x, x.toString());
        }
        return items;
    }

Answer 1

The problem was that I didn’t have the right collection of SelectItems when the user edited a business object. Plus that I added the <f:converter> to explicitly invoke the converter, where I did some changes in the getAsString() (the else part).

Thank you for your time, and hope the post can be useful to someone else.

SelectMenuOne

public String prepareEditOrganisationActivity() {
        current = (Activity) organisationActivityItems.getRowData();
        Sector sector = current.getCategory().getSector();
        CategoryController categoryBean = JsfUtil.findBean("categoryController", CategoryController.class);
        categorySelection = categoryBean.categoryItemsBySector(sector);

        return "EditActivity";
}

CategoryControllerConverter

...    
    @Override
    public String getAsString(FacesContext facesContext, UIComponent component, Object object) {
        if (object == null) {
            return null;
        }
        if (object instanceof Category) {
            Category o = (Category) object;
            return getStringKey(o.getIdCategory());
        }
        else {
            Category tmp = new Category();
            return getStringKey(tmp.getIdCategory());                
        }
    }