Populated UISelect components via Database

[Gregg Bolinger]

Here is how I deal with UISelect components and populating them with a database.

public class SomeBackingBean
{
   private List<IssueType> typeList;
 

public List getTypeList() {
 
        final ArrayList list = new ArrayList();
        final IssueTypeService typeService = (IssueTypeService)getAppContext().getBean("issueTypeService");
        typeList = typeService.getTypeList();
        for(IssueType t : typeList){
            list.add(new SelectItem(t.getId(), t.getType()));
        }
        return list;
    }
 

    public IssueType getType() {
        final IssueTypeService typeService = (IssueTypeService)getAppContext().getBean("issueTypeService");
        type = typeService.getTypeById(getVisit().getCurrentIssue().getIssueType().getId());
 
        return type;
    }
 
}

Now to discuss that second method. What happens when the page is posted back for whatever reason, validation error etc, is I have to know which value the select menu should be sitting on. So I have to get the value I stored in the bean and lookup that up in the database. Not a big deal really, just extra code. Here is the JSP section.

<h:selectOneMenu id="type" value="#{newIssueForm.visit.currentIssue.issueType.id}" styleClass="common-dropdown">
                <f:selectItem itemLabel="-Select Type of Issue-" itemValue="0"/>
                <f:selectItems value="#{newIssueForm.typeList}" />
            </h:selectOneMenu>

So you see, when the page is submitted I store the value in newIssueForm.visit.currentIssue.issueType.id where issueType is JavaBean IssueType and has a property called id. The selectItems calls the getTypeList method shown above to populate the list with all the values I need.

Now, I show all this to ask if this is the best way. Is there a cleaner, smoother, easier way to do this or am I going about it about the best way possible?

[Gregg Bolinger]

Ok, here is another way of handling this that I got through after some trial and error.

The following I placed in the constructor. I am currently looking for a better place to put this code.

selectOneMenu = new HtmlSelectOneMenu();
        final ArrayList list = new ArrayList();
        final IssueTypeService typeService = (IssueTypeService) getAppContext().getBean("issueTypeService");
        typeList = typeService.getTypeList();
        for (IssueType t : typeList) {
            list.add(new SelectItem(t.getId(), t.getType()));
        }
        UISelectItems items = new UISelectItems();
        items.setValue(list);
        selectOneMenu.getChildren().add(items);

I also have the following in the same backing bean

public HtmlSelectOneMenu getSelectOneMenu() {
        return selectOneMenu;
    }
 
    public void setSelectOneMenu(HtmlSelectOneMenu selectOneMenu) {
        this.selectOneMenu = selectOneMenu;
    }
 
 public Integer getTheType() {
        return theType;
    }
 
    public void setTheType(Integer theType) {
        this.theType = theType;
    }

<h:selectOneMenu value="#{testBean.theType}" binding="#{testBean.selectOneMenu}"/>

That seems to work as well. Not sure if it's really any better. But it uses component binding.

[Gregg Bolinger]

Ok, I was trying to get the JSP as simple as possible, so I was able to get rid of the value attribute. But at a cost.

Taking a bit from my code above, if I leave everything as is, I get an error that the value of selectOneMenu (whatever is chosen) is not a String and does not have a converter. Well, it's not a String, it's an Integer. Oddly, if I keep the value attribute with the getters and setters for it, I don't get this error. But with just the binding attribute I get this error. So I modified my code a bit to compinsate..

BEFORE

for (IssueType t : typeList) {
            list.add(new SelectItem(t.getId(), t.getType()));
        }

AFTER

for (IssueType t : typeList) {
            list.add(new SelectItem(String.valueOf(t.getId()), t.getType()));
        }

And everything works. Anyone know of a way to make a converter that works with this scenerio?