Two different SelectItems return single selected value - jsf

Question

I have a country class:
public class Country{
private Long id;
private String name;
}
and a person class that has two Country fields
public class Person{
private Country nationality;
private Country nationality2;
}
Now in JSF I use <f:selectItems> to return list of countries to select nationalities as following:
<h:form id="form1">
<h:selectOneMenu value="#{mybean.person.nationality.id}">
<f:selectItems value="#{mybean.countryList}" var="var" itemValue="#{var.id}"/>
</h:selectOneMenu>
<h:selectOneMenu value="#{mybean.person.nationality2.id}">
<f:selectItems value="#{mybean.countryList}" var="var" itemValue="#{var.id}"/>
</h:selectOneMenu>
<p:commandButton actionListener="#{mybean.save}" update="sometable #form"/>
</h:form>
Now the weird problem is that when I submit the form the value assigned to the second field (nationality2) is assigned to both nationality and nationality2 regardless of what has been selected for the first field. For example if the selected value for nationality is 1 and the selected value for nationality2 is 2, when I submit the form both fields have the value 2. Why is this occuring?
PS: JSF implementation is Mojarra 2.1.3

Answer 1

Your concrete problem is caused because you're setting copies of the same Country reference as selected value and then manipulating only the id property. All changes made in one reference get reflected in all other references as well.
E.g.
Country country = new Country();
person.setNationality1(country);
person.setNationality2(country);
country.setId(1); // Gets reflected in both nationalities!
You'd better set the whole Country entity as value instead of manipulating its properties. Create a Converter which converts between Country and id:
#FacesConverter(forClass=Country.class)
public class CountryConverter implements Converter {
#Override
public String getAsString(FacesContext context, UIComponent component, Object value) {
return (value instanceof Country) ? ((Country) value).getId() : null;
}
#Override
public Object getAsObject(FacesContext context, UIComponent component, String value) {
if (value == null || value.isEmpty()) {
return null;
}
if (!value.matches("\\d+")) {
throw new ConverterException(new FacesMessage("Invalid country ID: " + value));
}
Long countryId = Long.valueOf(value);
MyBean myBean = context.getApplication().evaluateExpressionGet(context, "#{myBean}", MyBean.class);
for (Country country : myBean.getCountries()) {
if (countryId.equals(country.getId())) {
return country;
}
}
throw new ConverterException(new FacesMessage("Unknown country ID: " + value));
}
}
and use it as follows:
<h:selectOneMenu value="#{mybean.person.nationality1}">
<f:selectItems value="#{mybean.countries}" var="country" itemValue="#{country}" itemLabel="#{country.name}" />
</h:selectOneMenu>
<h:selectOneMenu value="#{mybean.person.nationality2}">
<f:selectItems value="#{mybean.countries}" var="country" itemValue="#{country}" itemLabel="#{country.name}" />
</h:selectOneMenu>

Answer 2

Try to give your Second selectOneMenu another name for var. For Example:
<h:selectOneMenu value="#{mybean.person.nationality2.id}">
<f:selectItems value="#{mybean.countryList}" var="var2" itemValue="#{var2.code}"/>
</h:selectOneMenu>
Otherwise you overwrite your changes in the (first) variable var by changing the second selectOneMenu.
EDIT:
If it does not solve the problem, try for tests to create a second countryList (countryList2) and attach it to the second selectOneMenu.
If the value still stays the same, the failure must be in the getters or setters.