附件的 HTTP 响应标头内容处置

将 XML 文档写入浏览器的响应流，并使浏览器显示另存为"对话框.

Write an XML document to a browser's response stream and cause the browser to display a "Save As" dialog.

考虑以下 download() 方法:

  HttpServletResponse response = getResponse();

  BufferedWriter bw = new BufferedWriter( new OutputStreamWriter(
      response.getOutputStream() ) );

  String filename = "domain.xml";
  String mimeType = new MimetypesFileTypeMap().getContentType( filename );

  // Prints "application/octet-stream"
  System.out.println( "mimeType: " + mimeType );

  // response.setContentType( "text/xml;charset=UTF-8" );
  response.setContentType( mimeType );
  response.setHeader( "Content-Disposition", "attachment;filename="
      + filename );

  bw.write( getDomainDocument() );
  bw.flush();
  bw.close();

在 Firefox 中，XML 内容显示在浏览器窗口中.在 IE 7 中，不显示 XML 内容——您必须查看文档源.这两种情况都不是想要的结果.

In Firefox, the XML content is displayed in the browser window. In IE 7, the XML content is not displayed -- you have to view the document source. Neither situation is the desired result.

网页使用以下按钮代码:

The web page uses the following code for the button:

    <a4j:commandButton action="#{domainContent.download}" value="Create Domain" reRender="error" />

生成的 XML 不以 <?xml version="1.0"?> 开头，而 XML 内容类似于:

The XML that is generated does not start with <?xml version="1.0"?>, rather the XML content resembles:

<schema xmlns="http://www.jaspersoft.com/2007/SL/XMLSchema" version="1.0">
  <items>
    <item description="EDT Class Code" descriptionId="" label="EDT Class Code" labelId="" resourceId="as_pay_payrolldeduction.edtclass"/>
  </items>
  <resources>
    <jdbcTable datasourceId="JNDI" id="as_pay_payrolldeduction" tableName="as_pay.payrolldeduction">
      <fieldList>
        <field id="payamount" type="java.math.BigDecimal"/>
      </fieldList>
    </jdbcTable>
  </resources>
</schema>

更新 #1

注意以下代码行:

Update #1

Note the following line of code:

response.setHeader( "Content-Disposition", "attachment;filename=" + filename );

更新 #2

使用 是问题所在；常规 按预期执行.使用 可以防止 刷新任何错误消息.

Update #2

Using <a4j:commandButton ... /> is the problem; a regular <h:commandButton .../> performs as expected. Using the <h:commandBUtton .../> prevents the <a4j:outputPanel .../> from refreshing any error messages.

相关Seam 消息.

以下 MIME 类型不会触发另存为"对话框:

The following mime types do not trigger the "Save As" dialog:

• 应用程序/八位字节流"
• 文本/xml"
• 文本/纯文本"

哪些更改会导致 a4j:commandButton 触发另存为"对话框，以便提示用户保存 XML 文件(作为 domain.xml)?

What changes will cause the a4j:commandButton to trigger a "Save As" dialog box so that the user is prompted to save the XML file (as domain.xml)?

谢谢.