将bean属性绑定到在JSF中不起作用的元素值

问题描述 投票：1回答：1

我试图在JSF中创建一个表单来向我的数据库添加一个事件。我遇到的问题是bean属性没有更新，因此我总是得到空值。我错过了什么，或者我做错了什么。

我尝试使用h:commandButton而不是p:commandButton，但结果是一样的。我也尝试将bean的范围设置为session和request，但也无济于事。

这是JSF页面。

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

<h:head>
    <title>Event</title>
</h:head>

<h:body>

    <ui:include src="/WEB-INF/components/header.xhtml"/>

    <h:form>
        <p:panel id="panel" header="Event" style="margin-bottom:10px; align-content: center">

            <p:growl id="messages" showDetail="true"/>

            <h:panelGrid columns="2" cellpadding="5">
                <p:outputLabel value="Name: "><p:outputLabel style="color: red" value="*"/></p:outputLabel>
                <p:inputText name="name" id="name" required="true" value="#{eventUtilBean.name}"/>

                <p:outputLabel value="Description: "><p:outputLabel style="color: red" value="*"/></p:outputLabel>
                <p:inputTextarea id="description" name="description" rows="8" cols="100" counter="display"
                                 maxlength="1000" value="#{eventUtilBean.description}"
                                 counterTemplate="{0} characters remaining." autoResize="true" required="true"/>
                <br/>
                <h:outputText id="display"/>

                <p:outputLabel value="Time: "><p:outputLabel style="color: red"
                                                                           value="*"/></p:outputLabel>
                <p:calendar value="#{eventUtilBean.today}" mindate="#{eventUtilBean.today}" showOn="button"
                            pattern="dd/MM/yyyy HH:mm:ss"/>

                <p:outputLabel value="Picture: "><p:outputLabel style="color: red" value="*"/></p:outputLabel>
                <p:inputText name="picture" id="picture" required="true" value="#{eventUtilBean.pictureURL}"/>

                <p:outputLabel value="Category: "><p:outputLabel style="color: red" value="*"/></p:outputLabel>
                <p:selectOneMenu id="selectOneEventCategoryMenu" style="width:125px" value="#{eventUtilBean.category}">
                    <f:selectItems value="#{eventUtilBean.eventCategories}" var="eventCategory"
                                   itemValue="#{eventCategory.id}" itemLabel="#{eventCategory.name}"/>
                </p:selectOneMenu>

                <p:commandButton action="#{eventUtilBean.addEvent}" process="@this" value="Add event">
                    <f:ajax render="message"/>
                </p:commandButton>

            </h:panelGrid>
            <p:outputLabel id="message" value="#{eventUtilBean.message}"/>
        </p:panel>

    </h:form>

</h:body>
</html>

托管bean：

package beans;

import dao.EventCategoryDAO;
import dao.EventPostDAO;
import dao.PostDAO;
import model.EventCategory;
import model.EventPost;

import javax.annotation.PostConstruct;
import javax.faces.bean.ManagedBean;
import javax.faces.context.FacesContext;
import java.util.Date;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

@ManagedBean(name = "eventUtilBean")
public class EventUtilBean {

    private Date today = new Date();
    private List<EventCategory> eventCategories;
    private int category;
    private String message;
    private String name;
    private String description;
    private String pictureURL;
    private List<EventPost> allEvents;
    private static int i = 0;

    public Date getToday() {
        return new Date();
    }

    @PostConstruct
    private void init() {
        eventCategories = EventCategoryDAO.getAll();
        allEvents = EventPostDAO.getAllEventPosts(false);
        allEvents.addAll(EventPostDAO.getAllEventPosts(true));
        allEvents =
                allEvents.stream().sorted((e1, e2) -> e2.getTimestamp().compareTo(e1.getTimestamp())).collect(Collectors.toList());
        System.out.println("called");
    }

    public void setToday(Date today) {
        this.today = today;
    }

    public List<EventCategory> getEventCategories() {
        return eventCategories;
    }

    public void setEventCategories(List<EventCategory> eventCategories) {
        this.eventCategories = eventCategories;
    }

    public String addEvent() {
        System.out.println(name + " - " + description + " - " + pictureURL + " - " + category);
        if (name == null || name.equals("") || description == null || description.equals("") || pictureURL == null || pictureURL.equals("") || category < 1) {
            message = "Some fields were left empty.";
            return null;
        }
        EventPost post = EventPostDAO.addEventPost(name, description, pictureURL, today, category);
        if (post != null) {
            message = "You have successfully added a new event.";
            name = "";
            description = "";
            pictureURL = "";
            category = 0;
            allEvents.add(0, post);
        } else {
            message = "Error.";
        }
        return null;
    }

    private String mapContains(Map<String, String> map, List<String> keys) {
        for (String key : keys) {
            System.out.println(key + " - " + map.get(key));
            if (!map.containsKey(key)) {
                return "Greska. Niste unijeli " + key;
            }
        }
        return "OK";
    }

    public int getCategory() {
        return category;
    }

    public void setCategory(int category) {
        this.category = category;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public String getName() {
        System.out.println("get: " + name);
        return name;
    }

    public void setName(String name) {
        System.out.println("set: " + name);
        this.name = name;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public String getPictureURL() {
        return pictureURL;
    }

    public void setPictureURL(String pictureURL) {
        this.pictureURL = pictureURL;
    }

    public List<EventPost> getAllEvents() {
        return allEvents;
    }

    public void setAllEvents(List<EventPost> allEvents) {
        this.allEvents = allEvents;
    }

    public String updateDeleted() {
        Map<String, String> requestParamMap =
                FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap();
        if (requestParamMap.containsKey("eventId") && requestParamMap.containsKey("deleted")) {
            int eventId = Integer.parseInt(requestParamMap.get("eventId"));
            boolean deleted = Boolean.parseBoolean(requestParamMap.get("deleted"));
            PostDAO.updateDeleted(eventId, deleted);
            int index = allEvents.indexOf(new EventPost(eventId));
            if (index >= 0) {
                allEvents.get(index).setDeleted(deleted);
            }
        }
        return null;
    }

}

出于显而易见的原因，在此代码段中排除了get和set方法，以免混淆它。

我希望在用户输入一些值时更新值，这样当调用方法addEvent时，值会更新而不是null，但我得到的只是空值。

编辑：我已经更新了它包含整个bean的答案。

编辑2：截至目前已发生异常，我没有更改上面提供的代码。 Stacktrace如下：

06-Apr-2019 12:57:06.032 SEVERE [http-nio-8081-exec-50] com.sun.faces.context.AjaxExceptionHandlerImpl.handlePartialResponseError javax.faces.application.ViewExpiredException: viewId:/pages/body_add_event.xhtml - View /pages/body_add_event.xhtml could not be restored.
    at com.sun.faces.lifecycle.RestoreViewPhase.execute(RestoreViewPhase.java:210)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.RestoreViewPhase.doPhase(RestoreViewPhase.java:121)
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:198)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:646)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:668)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:791)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1417)
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.base/java.lang.Thread.run(Thread.java:844)

06-Apr-2019 12:57:06.044 SEVERE [http-nio-8081-exec-49] com.sun.faces.context.AjaxExceptionHandlerImpl.handlePartialResponseError javax.faces.application.ViewExpiredException: viewId:/pages/body_add_event.xhtml - View /pages/body_add_event.xhtml could not be restored.
    at com.sun.faces.lifecycle.RestoreViewPhase.execute(RestoreViewPhase.java:210)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.RestoreViewPhase.doPhase(RestoreViewPhase.java:121)
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:198)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:646)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:668)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:791)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1417)
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.base/java.lang.Thread.run(Thread.java:844)
jsf primefaces javabeans
1个回答
0
投票

ViewException只是因为会话已过期。重新加载应用程序，此错误将消失。

p：commandButton不仅应该处理@this，因为它只表示commandButton本身。尝试例如过程= “@形式”。

最新问题
© www.soinside.com 2019 - 2024. All rights reserved.