Функция бина никогда не вызывается

Question

У меня есть кнопка в Facelet, и когда я нажимаю на нее, я хочу вызвать функцию бина.Но вместо вызова функции, страница перезагружается и падает, потому что функция никогда не вызывается.

Когда я нажимаю <h:commandButton action="#{trainingsplanBean.changeWeek}" value="OK" />, функция changeWeek НЕ вызывается и страница перезагружается.Из-за отсутствующих данных приложение вылетает.

Facelet (XHTML-файл):

<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE composition PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<ui:composition
    xmlns="http://www.w3.org/1999/xhtml"
    xmlns:ui="http://xmlns.jcp.org/jsf/facelets"
    template="../WEB-INF/templates/internalTemplate.xhtml"
    xmlns:h="http://xmlns.jcp.org/jsf/html"
    xmlns:p="http://primefaces.org/ui"
    xmlns:f="http://xmlns.jcp.org/jsf/core">

    <ui:define name="content">
        <p align="center">
            <b style="color: red;">Bitte nicht vergessen die durchgef&uuml;hrten &Auml;nderungen mit einem Klick auf den "Speichern" Button zu sichern!</b>
            &nbsp;&nbsp;
            <h:commandButton value="Speichern!" class="button">
                <f:actionListener binding="#{trainingsplanBean.save()}" />
                <f:actionListener binding="#{bereichLaufenBean.save()}" />
                <f:actionListener binding="#{bereichRadfahrenBean.save()}" />
            </h:commandButton>
        </p>

        <div style="overflow-x: auto;" align="center">
            <table cellspacing="0" cellpadding="5" id="plan_table">
                <thead>
                    <tr>
                        <th colspan="2" rowspan="2" class="kw_cell tp_table_border">
                            KW&nbsp;
                            <h:selectOneMenu id="kw" value="#{trainingsplanBean.kw}">
                                <f:selectItems value="#{trainingsplanBean.weeks}" />
                            </h:selectOneMenu>
                            /
                            <h:selectOneMenu id="year" value="#{trainingsplanBean.year}">
                                <f:selectItems value="#{trainingsplanBean.years}" />
                                <f:ajax execute="year" render="kw" listener="#{trainingsplanBean.prepareWeeks()}" />
                            </h:selectOneMenu>
                            <h:commandButton action="#{trainingsplanBean.changeWeek}" value="OK" />
                            <h:commandButton action="#{trainingsplanBean.today}" value="Heute" immediate="true" />
                            <br />
                            <h:commandButton action="#{trainingsplanBean.prevWeek}" value="vorige Woche" immediate="true" /> <h:commandButton action="#{trainingsplanBean.nextWeek}" value="folgende Woche" immediate="true" />
                        </th>

                        <th class="date_cell tp_table_border"><h:outputText value="#{trainingsplanBean.getDayOfWeek(1)}" /><br />MO</th>
                        <th class="date_cell tp_table_border"><h:outputText value="#{trainingsplanBean.getDayOfWeek(2)}" /><br />DI</th>
                        <th class="date_cell tp_table_border"><h:outputText value="#{trainingsplanBean.getDayOfWeek(3)}" /><br />MI</th>
                        <th class="date_cell tp_table_border"><h:outputText value="#{trainingsplanBean.getDayOfWeek(4)}" /><br />DO</th>
                        <th class="date_cell tp_table_border"><h:outputText value="#{trainingsplanBean.getDayOfWeek(5)}" /><br />FR</th>
                        <th class="date_cell tp_table_border"><h:outputText value="#{trainingsplanBean.getDayOfWeek(6)}" /><br />SA</th>
                        <th class="date_cell tp_table_border"><h:outputText value="#{trainingsplanBean.getDayOfWeek(7)}" /><br />SO</th>

                        <th rowspan="2" style="font-weight: bold;" class="tp_table_border">GESAMT</th>
                    </tr>
                </thead>
                <tbody>
                    <!-- Schwimmen -->
                    <tr>
                        <td rowspan="4" class="type_cell schwimmen">Schwimmen</td>
                        <td class="desc_cell schwimmen">Ist-Zeit</td>

                        <td class="schwimmen"><p:calendar value="#{trainingsplanBean.getDay(1).schwimmen.istdauer}" timeOnly="true" pattern="HH:mm" /></td>
                        <td class="schwimmen"><p:calendar value="#{trainingsplanBean.getDay(2).schwimmen.istdauer}" timeOnly="true" pattern="HH:mm" /></td>
                        <td class="schwimmen"><p:calendar value="#{trainingsplanBean.getDay(3).schwimmen.istdauer}" timeOnly="true" pattern="HH:mm" /></td>
                        <td class="schwimmen"><p:calendar value="#{trainingsplanBean.getDay(4).schwimmen.istdauer}" timeOnly="true" pattern="HH:mm" /></td>
                        <td class="schwimmen"><p:calendar value="#{trainingsplanBean.getDay(5).schwimmen.istdauer}" timeOnly="true" pattern="HH:mm" /></td>
                        <td class="schwimmen"><p:calendar value="#{trainingsplanBean.getDay(6).schwimmen.istdauer}" timeOnly="true" pattern="HH:mm" /></td>
                        <td class="schwimmen"><p:calendar value="#{trainingsplanBean.getDay(7).schwimmen.istdauer}" timeOnly="true" pattern="HH:mm" /></td>

                        <td class="schwimmen tp_table_border"><h:outputText value="#{trainingsplanBean.wochensumme_schwimmen_istdauer_str()}" /></td>
                    </tr>

and so on ...

Bean:

@ManagedBean(name = "trainingsplanBean", eager = true)
@ViewScoped
public class TrainingsplanBean implements Serializable {
    public void changeWeek() {
        for (int i = 1; i <= 7; i++) {
            Date date = Utilities.getDayOfWeek(year, kw, i);
            System.out.println("CHANGE WEEK : DAY " + i);
            try {
                Trainingstag tag = TrainingsplanService.inst().readTrainingstag(getCurrentUser(), date);
                System.out.println(tag);
                trainingstage[i - 1] = tag;
            } catch (DatabaseException ex) {
            }
        }
    }
}