In a recent JSF project I found some difficulties how to use select items with persistent objects. I dont know where to put it, here or in the wiki .. so I just try here .
I want to share a solution which is based on http://wiki.jboss.org/wiki/Wiki.jsp?page=SelectItems.

Just add the interfaces and classes and you should be able to use select menus based on User objects:

package com.innflow.bj2.webapp.util.si;

import java.io.Serializable;
import java.util.List;
import java.util.Locale;
import java.util.Map;

import javax.faces.convert.Converter;

/**
 *
 * @author Rene Guenther rene.guenther@innflow.com
 *
 * @param <T>
 */
public interface BaseSIIntf<T> extends Serializable {
public Map<String, T> getSelectItems(Locale locale);

public Map<String, T> getSelectItems();

public List<T> getAllObjects();

public Converter getConverter();
}

package com.innflow.bj2.webapp.util.si;

import java.text.Collator;
import java.util.Comparator;
import java.util.Locale;

import com.innflow.bj2.model.LabelValueGeneric;
import com.innflow.bj2.webapp.action.BasePage;

/**
 *
 * @author Rene Guenther rene.guenther@innflow.com
 *
 */
public class BaseSI extends BasePage{
/**
* Class to compare LabelValues using their labels with locale-sensitive
* behaviour.
*/
public class LabelValueComparator implements Comparator<Object> {
private Comparator<Object> c;

/**
* Creates a new LabelValueComparator object.
*
* @param locale
* The Locale used for localized String comparison.
*/
public LabelValueComparator(Locale locale) {
c = Collator.getInstance(locale);
}

/**
* Compares the localized labels of two LabelValues.
*
* @param o1
* The first LabelValue to compare.
* @param o2
* The second LabelValue to compare.
*
* @return The value returned by comparing the localized labels.
*/
public final int compare(Object o1, Object o2) {
LabelValueGeneric lhs = (LabelValueGeneric) o1;
LabelValueGeneric rhs = (LabelValueGeneric) o2;

return c.compare(lhs.getLabel(), rhs.getLabel());
}
}
}

package com.innflow.bj2.webapp.util.si;

import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;

import javax.annotation.Resource;
import javax.faces.convert.Converter;

import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Controller;

import com.innflow.bj2.model.LabelValueGeneric;
import com.innflow.bj2.model.User;
import com.innflow.bj2.service.UserManager;
import com.innflow.bj2.webapp.jsf.ReferenceConverter;

/**
 * @author Rene Guenther rene.guenther@innflow.com
 */
@Controller("userSI")
@Scope("request")
public class UserSI extends BaseSI implements BaseSIIntf<User> {

/**
*
*/
private static final long serialVersionUID = 5816369678066099896L;

private UserManager manager;

private Map<String, User> selectItems;

private List<User> allObjects;

@Resource(name = "userManager")
public void setManager(UserManager manager) {
this.manager = manager;
}

public Map<String, User> getSelectItems() {
return getSelectItems(getRequest().getLocale());
}

public Map<String, User> getSelectItems(Locale locale) {
if (this.selectItems == null) {
allObjects = manager.getUsers(null);
List<LabelValueGeneric<User>> objects = new ArrayList<LabelValueGeneric<User>>();
for (User user : allObjects) {
final String label = user.getUsername() + " ("
+ user.getFullName() + ")";
objects.add(new LabelValueGeneric<User>(label, user));
}
if (null == locale)
Collections.sort(objects);
else
Collections.sort(objects, new LabelValueComparator(locale));

Map<String, User> options = new LinkedHashMap<String, User>();
for (LabelValueGeneric<User> lv : objects) {
options.put(lv.getLabel(), lv.getValue());
}
this.selectItems = options;
}
return this.selectItems;
}

public List<User> getAllObjects() {
if (allObjects == null) {
allObjects = manager.getUsers(null);
}
return allObjects;
}

public Converter getConverter() {
return new ReferenceConverter<User>(getAllObjects());
}
}

package com.innflow.bj2.webapp.jsf;

import java.io.Serializable;
import java.util.List;

import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.convert.Converter;
import javax.faces.convert.ConverterException;

/**
 *
 *
 * <p>
 * Based on http://wiki.jboss.org/wiki/Wiki.jsp?page=SelectItems
 *
 * @param <T>
 */
public class ReferenceConverter<T> implements Serializable, Converter {

/**
*
*/
private static final long serialVersionUID = -1100627491163130596L;

private static final String EMPTY = "__EMPTY__";

private List<T> values;

public ReferenceConverter(List<T> vals) {
this.values = vals;
}

public String getAsString(FacesContext facesContext, UIComponent component,
Object obj) {
if (obj == null)
return EMPTY;
if ("-1".equals(obj))
return EMPTY;

String val = String.valueOf(obj.hashCode());
return val;
}

public Object getAsObject(FacesContext facesContext, UIComponent component,
String str) throws ConverterException {
if (str == null || str.length() == 0 || EMPTY.equals(str)) {
return null;
}

int hash = Integer.valueOf(str).intValue();
for (T val : values) {
if (val != null && val.hashCode() == hash) {
return val;
}
}

return null;
}

}

Example usage on xhtml page:

<h:outputLabel for="refUser" styleClass="desc"
value="#{text['user.user']}" />
<t:message for="refUser" styleClass="fieldError" />
<t:selectOneMenu value="#{userForm.refUser}" id="refUser"
styleClass="select" disabled="#{!userForm.roleAdmin}" converter="#{userSI.converter}">
<f:selectItems value="#{userSI.selectItems}" />
</t:selectOneMenu>