Question

我正在使用spring webflow 1.0。我正在上传一个csv文件，解析它，并在继续之前显示结果。用户可以选择下载包含未通过验证的记录的csv文件。当我单击JSP中的链接下载此文件时，webflow将调用表单Action。表单操作通过从响应中获取输出流来写出文件：

HttpServletResponse response = ((ServletExternalContext) context.getExternalContext()).getResponse();

我不想离开我目前正在使用的jsp。我只想下载文件。换句话说，我不想过渡到另一个州。我只想提供动态呈现的文件。一切正常（我不会离开页面，我下载文件），但我的控制台出现以下错误：

_pEncydKfggPHJo8=org.springframework.webflow.engine.NoMatchingTransitionException: No transition was matched on the event(s) signaled by the [1] action(s) that executed in this action state 'downloadErrorReportAction' of flow 'myFlow'; transitions must be defined to handle action result outcomes -- possible flow configuration error? Note: the eventIds signaled were: 'array<String>[[null]]', while the supported set of transitional criteria for this action state is 'array<TransitionCriteria>[[empty]]'
    at org.springframework.webflow.engine.ActionState.doEnter(ActionState.java:187)
    at org.springframework.webflow.engine.State.enter(State.java:191)
    at org.springframework.webflow.engine.Transition.execute(Transition.java:212)
    at org.springframework.webflow.engine.TransitionableState.onEvent(TransitionableState.java:107)
    at org.springframework.webflow.engine.Flow.onEvent(Flow.java:534)
    Truncated. see log file for complete stacktrace

以下是我的webflow配置的相关部分。

<view-state id="showUploadResults" view="UploadResults3.0">
    <render-actions>
        <action bean="UploadResultsAction" method="transitionToWebflow"/>
        <action bean="UploadResultsAction" method="setupData"/>
    </render-actions>
    <transition on="submit" to="proceed"/>
    <transition on="downloadErrorReport" to="downloadErrorReportAction"/>
</view-state>

<action-state id="downloadErrorReportAction">
    <action bean="UploadResultsAction" method="downloadErrorReport" name="downloadErrorReport"/>
</action-state>

Answer 1

我能够通过定义视图状态并指定渲染操作来完成此操作。

<view-state id="downloadErrorReportAction">
        <render-actions>
            <action bean="uploadResultsAction" method="downloadErrorReport" name="downloadErrorReport"/>
        </render-actions>
    </view-state>

我还必须添加上一个操作中的相同转换，因为一旦单击下载链接，您将转换到另一个状态。所以最终的配置如下所示：

<view-state id="showUploadResults" view="UploadResults3.0">
   <render-actions>
      <action bean="UploadResultsAction" method="transitionToWebflow"/>
      <action bean="UploadResultsAction" method="setupData"/>
   </render-actions>
   <transition on="submit" to="proceed"/>
   <transition on="downloadErrorReport" to="downloadErrorReportAction"/>
</view-state>

<view-state id="downloadErrorReportAction">
     <render-actions>
         <action bean="uploadResultsAction" method="downloadErrorReport" name="downloadErrorReport"/>
     </render-actions>
    <transition on="submit" to="proceed"/>
</view-state>

Spring webflow 1.0 - 下载文件

1 个答案: