Question

I have a problem regarding jsf autocomplete elements. I want my page to have an autocomplete element and after a user selects a value from the field, another field is automatically created. The maksimum number of autocomplete field is 3, so after the 3rd one, the 4th one is disabled:

<h:outputLabel for="fieldsOfStudy" value="#{amsg.fieldsOfStudy}"/>

<p:outputPanel id="fieldsOfStudy" autoUpdate="true" layout="block">
     <ui:repeat value="#{cc.attrs.offer.fieldsOfStudy}" var="studyField" varStatus="status">

          <h:panelGroup id="studyField" layout="block">
              <h:outputText value="#{amsg.handleGetObject(enumHelper.toMessageKey(studyField))}"/>
              <p:commandLink action="#{cc.attrs.offer.removeFieldOfStudy(status.index)}" process="@this"
                       update="@([id$=fieldsOfStudyAutocomplete])" styleClass="ui-icon ui-icon-close"/>
          </h:panelGroup>

     </ui:repeat>
</p:outputPanel>

<h:message for="fieldsOfStudy" errorClass="error"/>

<h:panelGroup id="fieldsOfStudyAutocomplete">
     <p:autoComplete value="#{offerBean.selectedFieldOfStudy}" dropdown="true" required="#{empty cc.attrs.offer.fieldsOfStudy}"
                       completeMethod="#{offerBean.completeFieldsOfStudy}" disabled="#{cc.attrs.offer.fieldsOfStudy.size() &gt;= 3}"
                       itemValue="#{p}" var="p" itemLabel="#{amsg.handleGetObject(enumHelper.toMessageKey(p))}" styleClass="xLargeInput">
              <p:ajax event="itemSelect" process="@this" update="@this"/>
     </p:autoComplete>
</h:panelGroup>

Everything works good like this, but the problem is that every time a user presses the Save button if the “Field of study” list has 1 selected element from the autocomplete there will be another one in the list with a null value. If there are 2 selected “field of studies” the 3rd one will be also created but ill have a null value. If there are 3 selected “fields of studies”, then there wont be any 4th element in the list.

Is there any way I can set the autocomplete to ignore null fields? In other words, if a user doesnt select anything from the autocomplete, how not to pass null values to the DTO?

Answer 1

I found a way. When setting up the value in the bean you can easily put an if statement like this:

public void setSelectedFieldOfStudy(FieldOfStudy selectedFieldOfStudy) {
    if (selectedFieldOfStudy != null) {
        this.emptyOffer.getFieldsOfStudy().add(selectedFieldOfStudy);
    }
}