select one menu include search primefaces - primefaces

Question

primeFaces select oneMenu Show Cases has select advance .and it has one attribute ( converter ) .
primeFaces Code:
<p:selectOneMenu id="advanced" value="#{selectOneMenuView.theme}" converter="#{themeConverter}" panelStyle="width:180px"
effect="fade" var="t" style="width:160px" filter="true" filterMatchMode="startsWith">
<f:selectItems value="#{selectOneMenuView.themes}" var="theme" itemLabel="#{theme.displayName}" itemValue="#{theme}" />
<p:column style="width:10%">
<h:graphicImage name="showcase/images/themeswitcher/themeswitcher-#{t.name}.png" alt="#{t.name}" styleClass="ui-theme" />
</p:column>
<p:column>
<f:facet name="header">
<h:outputText value="Name"/>
</f:facet>
<h:outputText value="#{t.displayName}" />
</p:column>
<f:facet name="footer">
<p:separator />
<h:outputText value="#{selectOneMenuView.themes.size()} themes" style="font-weight:bold;"/>
</f:facet>
</p:selectOneMenu>
i'm looking for where's converter="#{themeConverter}" in the code (page.xhtml and manage Bean , class) i don't find it . they don't mention it(themeConverter) in other class whether annotation or class name or variable.
anybody has idea how use it ?
with example
thank you

Answer 1

ThemeConverter source code is right here:
https://github.com/primefaces/primefaces-showcase/blob/master/src/main/java/org/primefaces/showcase/convert/ThemeConverter.java
package org.primefaces.showcase.convert;
import javax.faces.application.FacesMessage;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.convert.Converter;
import javax.faces.convert.ConverterException;
import javax.faces.convert.FacesConverter;
import javax.inject.Inject;
import javax.inject.Named;
import org.primefaces.showcase.domain.Theme;
import org.primefaces.showcase.service.ThemeService;
#Named
#FacesConverter(value = "themeConverter", managed = true)
public class ThemeConverter implements Converter<Theme> {
#Inject private ThemeService themeService;
#Override
public Theme getAsObject(FacesContext context, UIComponent component, String value) {
if(value != null && value.trim().length() > 0) {
try {
return themeService.getThemes().get(Integer.parseInt(value));
} catch(NumberFormatException e) {
throw new ConverterException(new FacesMessage(FacesMessage.SEVERITY_ERROR, "Conversion Error", "Not a valid theme."));
}
}
else {
return null;
}
}
#Override
public String getAsString(FacesContext context, UIComponent component, Theme value) {
if(value != null) {
return String.valueOf(value.getId());
}
else {
return null;
}
}
}