/**
* <!-- START SNIPPET: description -->
*
* A custom Result type for sending raw data (via an InputStream) directly to the
* HttpServletResponse. Very useful for allowing users to download content.
*
* <!-- END SNIPPET: description -->
* <p/>
* <b>This result type takes the following parameters:</b>
*
* <!-- START SNIPPET: params -->
*
* <ul>
*
* <li><b>contentType</b> - the stream mime-type as sent to the web browser
* (default = <code>text/plain</code>).</li>
*
* <li><b>contentLength</b> - the stream length in bytes (the browser displays a
* progress bar).</li>
比如这段 是那个窗口可以显示
show view 里面的那个窗口啊 突然找不到了