jsf 2.0 Primefaces 多个 Fileupload 不记得上传的文件答案

【问题标题】：jsf 2.0 Primefaces multiple Fileupload does not remember uploaded filesjsf 2.0 Primefaces 多个 Fileupload 不记得上传的文件
【发布时间】：2013-12-16 13:38:29
【问题描述】：

我已经在这篇文章中修复了一些其他问题（fileuploadhandler 正在工作），我的代码如下：

豆：

@ManagedBean
@ViewScoped
public class TempBean implements Serializable{

    private static final long serialVersionUID = -70753689043016662L;
    private List<String> names; //to remember which files have been uploaded

    public void load(){
        System.out.println("@prerender");
    }

    public TempBean() {
        super();
        System.out.println("@constructor");
        names = new ArrayList<String>();
    }

    @PostConstruct
    public void pc(){
        System.out.println("@postconstruct");
    }

    public void handleFileUpload(FileUploadEvent event) { 
        String filename = event.getFile().getFileName();
        System.out.println("INCOMING FILE: " + filename);
        names.add(filename);

        if(!names.isEmpty()){
            System.out.println("Files uploaded:");
            for(String n : names){
                System.out.println("# " + n);
            }
            System.out.println();
        }
   }  

    public List<String> getNames() {
        return names; 
    }

    public void setNames(List<String> names) {
        this.names = names;
    }

}

xhtml 页面：

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
        xmlns:f="http://java.sun.com/jsf/core"
        xmlns:h="http://java.sun.com/jsf/html"
        xmlns:ui="http://java.sun.com/jsf/facelets"
        xmlns:p="http://primefaces.org/ui" >

    <h:head> 
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    </h:head>

    <f:event type="preRenderView" listener="#{tempBean.load}" />
    <h:body>

        <h:form>
            <p:fileUpload
                fileUploadListener="#{tempBean.handleFileUpload}"
                mode="advanced" dragDropSupport="true" multiple="true" update=":overview" />
        </h:form>

        <h:panelGroup id="overview">
            <ui:repeat var="file" value="#{tempBean.names}">
                #{file} <br/>
            </ui:repeat>
        </h:panelGroup>

    </h:body>
</html>

我现在面临的问题（或我打开新问题的原因）是，当我上传多个（例如三个）文件时，只有一个文件附加到空列表中。当我再次重新上传剩余的两个文件时，只有其中一个被附加到列表中。

有趣的是每个文件都会调用handleFileUpload(...) ...

这是我同时上传三个文件时的控制台输出：

@constructor
@postconstruct
@prerender
INCOMING FILE: test1.jpe
INCOMING FILE: test3.jpe
Files uploaded:
INCOMING FILE: test2.jpe
# test3.jpe
-END OF LIST-
Files uploaded:
# test1.jpe
Files uploaded:
# test2.jpe
-END OF LIST-
-END OF LIST-
@prerender
@prerender
@prerender

如何使文件上传组件正常运行？这是 bug 还是 ajax 问题？

这是我的 web.xml：

<?xml version="1.0" encoding="UTF-8"?>
<web-app 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xmlns="http://java.sun.com/xml/ns/javaee" 
xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" 
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" 
id="WebApp_ID" version="3.0" >

  <display-name>TestProjekt</display-name>
  <welcome-file-list>
    <welcome-file>test.xhtml</welcome-file>
  </welcome-file-list>
  <servlet>
    <servlet-name>Faces Servlet</servlet-name>
    <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
  </servlet>

    <servlet-mapping>
        <servlet-name>Faces Servlet</servlet-name>
        <url-pattern>/faces/*</url-pattern>
    </servlet-mapping>
    <servlet-mapping>
        <servlet-name>Faces Servlet</servlet-name>
        <url-pattern>*.jsf</url-pattern>
    </servlet-mapping>
    <servlet-mapping>
        <servlet-name>Faces Servlet</servlet-name>
        <url-pattern>*.faces</url-pattern>
    </servlet-mapping>
    <servlet-mapping> 
        <servlet-name>Faces Servlet</servlet-name>
        <url-pattern>*.xhtml</url-pattern>
    </servlet-mapping>

    <context-param>
        <param-name>javax.servlet.jsp.jstl.fmt.localizationContext</param-name>
        <param-value>resources.application</param-value>
    </context-param>
    <context-param>
        <description>State saving method: 'client' or 'server' (=default). See JSF Specification 2.5.2</description>
        <param-name>javax.faces.STATE_SAVING_METHOD</param-name>
        <param-value>client</param-value>
    </context-param>
    <context-param>
        <param-name>facelets.SKIP_COMMENTS</param-name>
        <param-value>true</param-value>
    </context-param>

    <context-param>
        <param-name>primefaces.UPLOADER</param-name>
        <param-value>commons</param-value>
    </context-param>

  <context-param>
    <description>
    This parameter tells MyFaces if javascript code should be allowed in
    the rendered HTML output.
    If javascript is allowed, command_link anchors will have javascript code
    that submits the corresponding form.
    If javascript is not allowed, the state saving info and nested parameters
    will be added as url parameters.
    Default is 'true'</description>
    <param-name>org.apache.myfaces.ALLOW_JAVASCRIPT</param-name>
    <param-value>true</param-value>
  </context-param>

      <context-param> 
        <description> 
        If true, rendered HTML code will be formatted, so that it is 'human-readable'
        i.e. additional line separators and whitespace will be written, that do not
        influence the HTML code.
        Default is 'true'</description>
        <param-name>org.apache.myfaces.PRETTY_HTML</param-name>
        <param-value>true</param-value>
      </context-param>

      <context-param>
        <param-name>org.apache.myfaces.DETECT_JAVASCRIPT</param-name>
        <param-value>false</param-value>
      </context-param>

      <context-param>
        <description>
        If true, a javascript function will be rendered that is able to restore the
        former vertical scroll on every request. Convenient feature if you have pages
        with long lists and you do not want the browser page to always jump to the top
        if you trigger a link or button action that stays on the same page.
        Default is 'false'
        </description>
        <param-name>org.apache.myfaces.AUTO_SCROLL</param-name>
        <param-value>true</param-value>
      </context-param>


    <filter> 
        <filter-name>PrimeFaces FileUpload Filter</filter-name>
        <filter-class>org.primefaces.webapp.filter.FileUploadFilter</filter-class>
        <init-param>
            <param-name>uploadDirectory</param-name>
            <param-value>C:\tmp</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>PrimeFaces FileUpload Filter</filter-name>
        <servlet-name>Faces Servlet</servlet-name>
    </filter-mapping>

</web-app>

还有我的 faces.config：

<?xml version="1.0" encoding="UTF-8"?>
<faces-config
    xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-facesconfig_2_0.xsd"
    version="2.0"> 

</faces-config>

【问题讨论】：

只有我有这个问题吗？
究竟哪个 JSF impl/version 和哪个 PF 版本？请不要说“JSF 2.0”。这是一个规范版本，它没有详细说明正在使用的实现及其（子）版本。另请参阅stackoverflow.com/tags/jsf/info 的顶部部分
嗨，我目前正在使用 PF 4.0（社区下载）和 JSF 2.0 Apache Myfaces-2.2.0-20130426。 (雄猫 7)
好的，您的faces-config.xml 的根声明到底是什么样的？你们在web.xml 中声明的PrimeFaces 文件上传配置到底是什么？
嗨，刚刚尝试使用 MyFaces 2.2.0 beta 重现它，目前在 myfaces.apache.org/download.html 上可用我无法重现它，它对我来说很好用。我找不到你在那里使用的 20130426 版本，但日期表明是早期的 alpha 版本。我建议选择最新的可用版本（2.2.0 测试版）并尝试一下。

标签： ajax file-upload jsf-2 primefaces drag-and-drop

【解决方案1】：

这是由您的 JSF 实现 MyFaces 2.2.0-20130426 中的错误引起的。

当我尝试 MyFaces 2.2.0-beta（目前在 myfaces.apache.org 提供）和 Mojarra 2.2.4（目前在 javaserverfaces.java.net 提供）时，它对我有用。

正如 cmets 在该问题上所证实的那样，它也适用于您。

【讨论】：