Question

我的p：fileUpload有问题。在我的Bean中，它在我加载文件时检索空值。我使用PrimeFaces3.5

这是我的.xhtml

    xmlns:f="http://xmlns.jcp.org/jsf/core"
    xmlns:p="http://primefaces.org/ui">
    <h:head>
    <title>Facelet Title</title>
    </h:head>
    <h:body>
    <h:form enctype="multipart/form-data">  
        <p:messages showDetail="true"/> 
        <p:panelGrid columns="2">
            <h:outputLabel for="image" value="Select Picture" />
            <p:fileUpload value="#{uploadImage.file}" mode="advance" allowTypes="/(\.|\/)(gif|jpe?g|png)$/"/> 

                <p:commandButton value="Submit" ajax="false" 
                                 action="#{uploadImage.test1()}"/>
        </p:panelGrid>
        </h:form>
    </h:body>
    </html>

这是UploadImage.java

    package AS_2;
    import java.io.Serializable;
    import javax.faces.application.FacesMessage;
    import javax.faces.bean.ManagedBean;
    import javax.faces.bean.SessionScoped;
    import javax.faces.context.FacesContext;
    import org.primefaces.event.FileUploadEvent;
    import org.primefaces.model.UploadedFile;

    /**
     *
     * @author Mac
     */
    @ManagedBean
    @SessionScoped
    public class UploadImage implements Serializable{
    private UploadedFile file;

        public UploadedFile getFile() {
            return file;
        }

        public void setFile(UploadedFile file) {
            this.file = file;
        }
        /**
         * Creates a new instance of UploadImage
         */

        public void test1() {
        try {
             if (file != null) {
            FacesMessage msg = new FacesMessage("Succesful is uploaded.");
            FacesContext.getCurrentInstance().addMessage(null, msg);
             } else {
            FacesMessage msg = new FacesMessage("failure to upload");
            FacesContext.getCurrentInstance().addMessage(null, msg);
            }
        } catch (Exception e) {
        e.printStackTrace();
           }
        }
        public UploadImage() {
        }

    }

web.xml就像是：

 <?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.1" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd">
    <context-param>
        <param-name>javax.faces.PROJECT_STAGE</param-name>
        <param-value>Development</param-value>
    </context-param>
    <context-param>
        <param-name>javax.faces.CONFIG_FILES</param-name>
        <param-value>/WEB-INF/faces-config.xml</param-value>
    </context-param>
    <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>*.xhtml</url-pattern> 
    </servlet-mapping>
    <session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>
    <welcome-file-list>
        <welcome-file>faces/mainPage.xhtml</welcome-file>
    </welcome-file-list>
    <filter>
        <filter-name>PrimeFaces FileUpload Filter</filter-name>
        <filter-class>org.primefaces.webapp.filter.FileUploadFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>PrimeFaces FileUpload Filter</filter-name>
        <servlet-name>Faces Servlet</servlet-name>
        <dispatcher>FORWARD</dispatcher>
    </filter-mapping>
    <filter>
        <filter-name>Extensions Filter</filter-name>
        <filter-class>org.apache.myfaces.webapp.filter.ExtensionsFilter</filter-class> 
    </filter>
    <filter-mapping>
        <filter-name>Extensions Filter</filter-name>
        <servlet-name>Faces Servlet</servlet-name>
    </filter-mapping>
    <filter-mapping>
    <filter-name>Extensions Filter</filter-name>
    <url-pattern>/faces/myFacesExtensionResource/*</url-pattern>
    </filter-mapping>
     <filter-mapping>
    <filter-name>Extensions Filter</filter-name>
    <url-pattern>*.jsf</url-pattern>
    </filter-mapping>
    <filter-mapping>
    <filter-name>Extensions Filter</filter-name>
    <url-pattern>*.xhtml</url-pattern>
    </filter-mapping>
  </web-app>

这是我的faces-config.xml

    <?xml version='1.0' encoding='UTF-8'?>
<faces-config version="2.2"
    xmlns="http://xmlns.jcp.org/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-facesconfig_2_2.xsd">
    <render-kit>
        <renderer>
            <component-family>org.primefaces.component</component-family>
            <renderer-type>org.primefaces.component.FileUploadRenderer</renderer-type>
            <renderer-class>AS_2.MyFileUploadRenderer</renderer-class>
        </renderer>
    </render-kit>

</faces-config>

请告诉我这件事。

Answer 1

<p:fileUpload value="#{uploadImage.file}" 
mode="advance" allowTypes="/(\.|\/)(gif|jpe?g|png)$/"/>

在您的代码中，您遗漏了fileUploadListener。将上面的代码添加到：

 <p:fileUpload value="#{uploadImage.file}" 
   fileUploadListener="#{uploadImage.handleFileUpload}"
   mode="advance" allowTypes="/(\.|\/)(gif|jpe?g|png)$/"/>

然后在UploadImageBean，

public void handleFileUpload(FileUploadEvent event) {  
        this.file=event.getFile();
    }

您不能只在value中拥有p:fileUpload，还需要fileUploadListener。我希望有所帮助。

Answer 2

您已在web.xml文件中注释了文件上传过滤器。

取消注释这些行。

<filter>
   <filter-name>PrimeFaces FileUpload Filter</filter-name>
   <filter-class>org.primefaces.webapp.filter.FileUploadFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>PrimeFaces FileUpload Filter</filter-name>
    <servlet-name>Faces Servlet</servlet-name>
    <dispatcher>FORWARD</dispatcher>
</filter-mapping>

此外，如果您使用高级模式，请不要使用value属性，因为您在侦听器中管理上传的文件。

p：fileUpload返回null值

2 个答案: