JSF2上传文件总是不能得到或者后台事件不能触发

今天犯2了,以前还帮助别人解决过这样的问题.结果同样的问题却发生在自己身上,实在羞愧.所以写此文记下.

 

原因是忘记加入FileUploadFilter到web.xml . 

<filter>
    <filter-name>PrimeFaces FileUpload Filter</filter-name>
    <filter-class>org.primefaces.webapp.filter.FileUploadFilter</filter-class>
    <init-param>
      <param-name>thresholdSize</param-name>
      <param-value>20480</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>PrimeFaces FileUpload Filter</filter-name>
    <servlet-name>Faces Servlet</servlet-name>
  </filter-mapping>

 

当然如果你用的 simple 模式, 记得表单上加上 enctype="multipart/form-data" . 

<h:form enctype="multipart/form-data">  
  
    <p:messages showDetail="true"/>  
  
    <p:fileUpload value="#{fileUploadController.file}" mode="simple"/>  
  
    <p:commandButton value="Submit" ajax="false"  
                actionListener="#{fileUploadController.upload}"/>  
  
</h:form>