Ajax Call get null value in backing bean in jsf - ajax

Question

I have two SelectoneMenu and one inputText. within inputText I called one Ajax event(blur). But this ajax method does not get selected value from SelectoneMenu. But I called the same method using CommandButton it will get selected values and worked fine.
Here is My Code:
<h:form id=HarvestRateForm>
<table width="670px;">
<tr>
<td width="100px;"><p:outputLabel value="Crushing Season" for="crushingSeason"/></td>
<td width="80px;">
<p:selectOneMenu id="crushingSeason" style="width: 110px;" value="#{harvestRateBean.selectedSeason}">
<f:selectItem itemValue="#{null}" itemLabel="Select"/>
<f:selectItems value="#{harvestRateBean.seasons}"/>
</p:selectOneMenu><p:growl for="crushingSeason"/>
</td>
<td width="60px;" align="right"><p:outputLabel value="Plant" for="plant"/></td>
<td width="80px;"><p:selectOneMenu id="plant" style="width: 85px;" value="#{harvestRateBean.selectedPlant}">
<f:selectItem itemValue="#{null}" itemLabel="Select"/>
<f:selectItems value="#{harvestRateBean.plants}"/>
</p:selectOneMenu><p:growl for="plant"/></td>
<td width="60px;" align="right"><p:outputLabel value="Plot No" for="plotNo"/></td>
<td><p:inputText id="plotNo" value="#{harvestRateBean.sapPlotNo}" size="16">
<p:ajax event="blur" listener="#{harvestRateBean.loadPlotDetails}"
update="HarvestRateForm:plotNo HarvestRateForm:ryotCode"/>
</p:inputText>
<p:growl for="plotNo"/>
</td>
</tr>
<tr>
<td><p:outputLabel value="Ryot No" for="ryotCode"/></td>
<td><p:inputText value="#{harvestRateBean.ryotNo}" size="15" id="ryotCode" readonly="true" style="background: transparent;background-color: #cccccc"/></td>
My Bean Class:
public class HarvestRateBean implements Serializable {
private Map<String, String> seasons;
private Map<String, String> plants;
private String selectedPlant;
private String selectedSeason;
private String sapPlotNo;
private String ryotNo;
public HarvestRateBean() {
seasons = new HashMap<String, String>();
plants = new HashMap<String, String>();
}
public Map<String, String> getSeasons() {
List<Season> season_list = loadSeason();
for (Iterator<Season> it = season_list.iterator(); it.hasNext();) {
Season season1 = it.next();
seasons.put(season1.getSeason(), season1.getSeason());
}
return seasons;
}
public void setSeasons(Map<String, String> seasons) {
this.seasons = seasons;
}
public List<Season> loadSeason() {
Session session = HibernateUtil.getSessionFactory().openSession();
List<Season> seasonlist = null;
try {
seasonlist = session.createCriteria(Season.class).list();
} catch (Exception ex) {
ex.printStackTrace();
} finally {
session.close();
HibernateUtil.getSessionFactory().close();
}
return seasonlist;
}
public Map<String, String> getPlants() {
List<Plant> plant_list = loadPlants();
for (Iterator<Plant> it = plant_list.iterator(); it.hasNext();) {
Plant plant = it.next();
plants.put(plant.getId().getPlant(), plant.getId().getPlant());
}
return plants;
}
public void setPlants(Map<String, String> plants) {
this.plants = plants;
}
public List<Plant> loadPlants() {
Session session = HibernateUtil.getSessionFactory().openSession();
List<Plant> plantlist = null;
try {
plantlist = session.createCriteria(Plant.class).list();
} catch (Exception ex) {
ex.printStackTrace();
} finally {
session.close();
}
return plantlist;
}
public String getSelectedPlant() {
return selectedPlant;
}
public void setSelectedPlant(String selectedPlant) {
this.selectedPlant = selectedPlant;
}
public String getSelectedSeason() {
return selectedSeason;
}
public void setSelectedSeason(String selectedSeason) {
this.selectedSeason = selectedSeason;
}
public String getSapPlotNo() {
return sapPlotNo;
}
public void setSapPlotNo(String sapPlotNo) {
this.sapPlotNo = sapPlotNo;
}
public String getRyotNo() {
return ryotNo;
}
public void setRyotNo(String ryotNo) {
this.ryotNo = ryotNo;
}
public void loadPlotDetails {
Session session = HibernateUtil.getSessionFactory().openSession();
List<HarvesterRate> rateList = null;
FacesContext context = FacesContext.getCurrentInstance();
try {
if (getSelectedSeason() == null || getSelectedSeason().isEmpty()) {
context.addMessage(null, new FacesMessage("Season is required", ""));
} else if (getSelectedPlant() == null || getSelectedPlant().isEmpty()) {
context.addMessage(null, new FacesMessage("Plant is required", ""));
} else if (getSapPlotNo() == null || getSapPlotNo().isEmpty()) {
context.addMessage(null, new FacesMessage("Plot No is required", ""));
} else {
rateList = session.createCriteria(HarvesterRate.class).add(Restrictions.eq("id.season", getSelectedSeason())).add(Restrictions.eq("id.plant", getSelectedPlant())).add(Restrictions.eq("id.plotNo", getSapPlotNo())).list();
if (rateList.size() > 0) {
for (Iterator<HarvesterRate> it = rateList.iterator(); it.hasNext();) {
HarvesterRate harvesterRate = it.next();
setSapPlotNo(harvestRate.getPlotNo());
setRyotNo(harvestRate.getVendorCode());
}
}
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
getSelectedSeason() and getSelectedPlant() always return null in ajax Call but I Called same method using CommandButton it return Selected value and everything works fine.

Answer 1

The <p:ajax> will by default process only the parent ClientBehavior component, which is in your particular case the <p:inputText>. In other words, the actual value of <p:ajax process> is #this. If you actually want to process the entire form, then you should be using #form as in
<p:inputText ...>
<p:ajax process="#form" ... />
</p:inputText>
The process attribute of <p:commandButton> defaults to #form, that's why it works therewith.
Or, if you have more input components in the form and intend to process only the input and those two dropdowns, then you can specify the (relative) client IDs space separated:
<p:inputText ...>
<p:ajax process="crushingSeason plant #this" ... />
</p:inputText>

Answer 2

Implement ajaxEvent in bean class
Ajax event is not like normal method rather than it invokes the listeners as input, you can configure the Blur action on a text field as following
In JSF page
<p:inputText id="name" value="#{loginBean.name}">
<f:ajax event="blur" listener="#{loginBean.ajaxEvent}" />
</p:inputText>
Ensure that the above must be inside in <h:form>
In ManagedBean class
public void ajaxEvent(AjaxBehaviorEvent e)
{
//Do your stuffs
}
Know more about JSF start from here