mimetype

<!--一些特殊后缀文件的处理x-msdownload表示下载,vnd.ms-word表示当前位置打开-->

JSP文件下载及出现getOutputStream() has already been called for this response的解决方法

http://iamin.blogdriver.com/iamin/1072546.html

一、采用RequestDispatcher的方式进行

1、web.xml文件中增加
  <mime-mapping>
    <extension>doc</extension>
    <mime-type>application/vnd.ms-word</mime-type>
  </mime-mapping>


2、程序如下：

<%@page language="java" import="java.net.*" pageEncoding="gb2312"%>
<%
    response.setContentType("application/x-download");//设置为下载application/x-download
    String filenamedownload = "/系统解决方案.doc";//即将下载的文件的相对路径
    String filenamedisplay = "系统解决方案.doc";//下载文件时显示的文件保存名称
    filenamedisplay = URLEncoder.encode(filenamedisplay,"UTF-8");
    response.addHeader("Content-Disposition","attachment;filename=" + filenamedisplay);
   
    try
    {
        RequestDispatcher dispatcher = application.getRequestDispatcher(filenamedownload);
        if(dispatcher != null)
        {
            dispatcher.forward(request,response);
        }
        response.flushBuffer();
    }
    catch(Exception e)
    {
        e.printStackTrace();
    }
    finally
    {
   
    }
%>


二、采用文件流输出的方式下载

1、web.xml文件中增加
  <mime-mapping>
    <extension>doc</extension>
    <mime-type>application/vnd.ms-word</mime-type>
  </mime-mapping>


2、程序如下：

<%@page language="java" contentType="application/x-msdownload" import="java.io.*,java.net.*" pageEncoding="gb2312"%><%
    //关于文件下载时采用文件流输出的方式处理：
    //加上response.reset()，并且所有的％>后面不要换行，包括最后一个；
    //因为Application Server在处理编译jsp时对于％>和<％之间的内容一般是原样输出，而且默认是PrintWriter，
    //而你却要进行流输出：ServletOutputStream，这样做相当于试图在Servlet中使用两种输出机制，
    //就会发生：getOutputStream() has already been called for this response的错误
    //详细请见《More Java Pitfill》一书的第二部分 Web层Item 33：试图在Servlet中使用两种输出机制 270
    //而且如果有换行，对于文本文件没有什么问题，但是对于其它格式，比如AutoCAD、Word、Excel等文件
    //下载下来的文件中就会多出一些换行符0x0d和0x0a，这样可能导致某些格式的文件无法打开，有些也可以正常打开。

    response.reset();//可以加也可以不加
    response.setContentType("application/x-download");//设置为下载application/x-download
    // /../../退WEB-INF/classes两级到应用的根目录下去，注意Tomcat与WebLogic下面这一句得到的路径不同，WebLogic中路径最后没有/
    System.out.println(this.getClass().getClassLoader().getResource("/").getPath());
    String filenamedownload = this.getClass().getClassLoader().getResource("/").getPath() + "/../../系统解决方案.doc";
    String filenamedisplay = "系统解决方案.doc";//系统解决方案.txt
    filenamedisplay = URLEncoder.encode(filenamedisplay,"UTF-8");
    response.addHeader("Content-Disposition","attachment;filename=" + filenamedisplay);

    OutputStream output = null;
    FileInputStream fis = null;
    try
    {
        output  = response.getOutputStream();
        fis = new FileInputStream(filenamedownload);

        byte[] b = new byte[1024];
        int i = 0;

        while((i = fis.read(b)) > 0)
        {
            output.write(b, 0, i);
        }
        output.flush();
    }
    catch(Exception e)
    {
        System.out.println("Error!");
        e.printStackTrace();
    }
    finally
    {
        if(fis != null)
        {
            fis.close();
            fis = null;
        }
        if(output != null)
        {
            output.close();
            output = null;
        }
    }
%>

=================================================
<mime-mapping>
        <extension>abs</extension>
        <mime-type>audio/x-mpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>ai</extension>
        <mime-type>application/postscript</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>aif</extension>
        <mime-type>audio/x-aiff</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>aifc</extension>
        <mime-type>audio/x-aiff</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>aiff</extension>
        <mime-type>audio/x-aiff</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>aim</extension>
        <mime-type>application/x-aim</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>art</extension>
        <mime-type>image/x-jg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>asf</extension>
        <mime-type>video/x-ms-asf</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>asx</extension>
        <mime-type>video/x-ms-asf</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>au</extension>
        <mime-type>audio/basic</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>avi</extension>
        <mime-type>video/x-msvideo</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>avx</extension>
        <mime-type>video/x-rad-screenplay</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>bcpio</extension>
        <mime-type>application/x-bcpio</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>bin</extension>
        <mime-type>application/octet-stream</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>bmp</extension>
        <mime-type>image/bmp</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>body</extension>
        <mime-type>text/html</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>cdf</extension>
        <mime-type>application/x-cdf</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>cer</extension>
        <mime-type>application/x-x509-ca-cert</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>class</extension>
        <mime-type>application/java</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>cpio</extension>
        <mime-type>application/x-cpio</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>csh</extension>
        <mime-type>application/x-csh</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>css</extension>
        <mime-type>text/css</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>dib</extension>
        <mime-type>image/bmp</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>doc</extension>
        <mime-type>application/msword</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>dtd</extension>
        <mime-type>text/plain</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>dv</extension>
        <mime-type>video/x-dv</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>dvi</extension>
        <mime-type>application/x-dvi</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>eps</extension>
        <mime-type>application/postscript</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>etx</extension>
        <mime-type>text/x-setext</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>exe</extension>
        <mime-type>application/octet-stream</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>gif</extension>
        <mime-type>image/gif</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>gtar</extension>
        <mime-type>application/x-gtar</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>gz</extension>
        <mime-type>application/x-gzip</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>hdf</extension>
        <mime-type>application/x-hdf</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>hqx</extension>
        <mime-type>application/mac-binhex40</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>htc</extension>
        <mime-type>text/x-component</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>htm</extension>
        <mime-type>text/html</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>html</extension>
        <mime-type>text/html</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>hqx</extension>
        <mime-type>application/mac-binhex40</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>ief</extension>
        <mime-type>image/ief</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>jad</extension>
        <mime-type>text/vnd.sun.j2me.app-descriptor</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>jar</extension>
        <mime-type>application/java-archive</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>java</extension>
        <mime-type>text/plain</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>jnlp</extension>
        <mime-type>application/x-java-jnlp-file</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>jpe</extension>
        <mime-type>image/jpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>jpeg</extension>
        <mime-type>image/jpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>jpg</extension>
        <mime-type>image/jpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>js</extension>
        <mime-type>text/javascript</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>jsf</extension>
        <mime-type>text/plain</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>jspf</extension>
        <mime-type>text/plain</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>kar</extension>
        <mime-type>audio/x-midi</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>latex</extension>
        <mime-type>application/x-latex</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>m3u</extension>
        <mime-type>audio/x-mpegurl</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mac</extension>
        <mime-type>image/x-macpaint</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>man</extension>
        <mime-type>application/x-troff-man</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>me</extension>
        <mime-type>application/x-troff-me</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mid</extension>
        <mime-type>audio/x-midi</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>midi</extension>
        <mime-type>audio/x-midi</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mif</extension>
        <mime-type>application/x-mif</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mov</extension>
        <mime-type>video/quicktime</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>movie</extension>
        <mime-type>video/x-sgi-movie</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mp1</extension>
        <mime-type>audio/x-mpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mp2</extension>
        <mime-type>audio/x-mpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mp3</extension>
        <mime-type>audio/x-mpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mpa</extension>
        <mime-type>audio/x-mpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mpe</extension>
        <mime-type>video/mpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mpeg</extension>
        <mime-type>video/mpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mpega</extension>
        <mime-type>audio/x-mpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mpg</extension>
        <mime-type>video/mpeg</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>mpv2</extension>
        <mime-type>video/mpeg2</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>ms</extension>
        <mime-type>application/x-wais-source</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>nc</extension>
        <mime-type>application/x-netcdf</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>oda</extension>
        <mime-type>application/oda</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>pbm</extension>
        <mime-type>image/x-portable-bitmap</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>pct</extension>
        <mime-type>image/pict</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>pdf</extension>
        <mime-type>application/pdf</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>pgm</extension>
        <mime-type>image/x-portable-graymap</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>pic</extension>
        <mime-type>image/pict</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>pict</extension>
        <mime-type>image/pict</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>pls</extension>
        <mime-type>audio/x-scpls</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>png</extension>
        <mime-type>image/png</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>pnm</extension>
        <mime-type>image/x-portable-anymap</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>pnt</extension>
        <mime-type>image/x-macpaint</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>ppm</extension>
        <mime-type>image/x-portable-pixmap</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>ppt</extension>
        <mime-type>application/powerpoint</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>ps</extension>
        <mime-type>application/postscript</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>psd</extension>
        <mime-type>image/x-photoshop</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>qt</extension>
        <mime-type>video/quicktime</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>qti</extension>
        <mime-type>image/x-quicktime</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>qtif</extension>
        <mime-type>image/x-quicktime</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>ras</extension>
        <mime-type>image/x-cmu-raster</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>rgb</extension>
        <mime-type>image/x-rgb</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>rm</extension>
        <mime-type>application/vnd.rn-realmedia</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>roff</extension>
        <mime-type>application/x-troff</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>rtf</extension>
        <mime-type>application/rtf</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>rtx</extension>
        <mime-type>text/richtext</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>sh</extension>
        <mime-type>application/x-sh</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>shar</extension>
        <mime-type>application/x-shar</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>smf</extension>
        <mime-type>audio/x-midi</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>sit</extension>
        <mime-type>application/x-stuffit</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>snd</extension>
        <mime-type>audio/basic</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>src</extension>
        <mime-type>application/x-wais-source</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>sv4cpio</extension>
        <mime-type>application/x-sv4cpio</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>sv4crc</extension>
        <mime-type>application/x-sv4crc</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>swf</extension>
        <mime-type>application/x-shockwave-flash</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>t</extension>
        <mime-type>application/x-troff</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>tar</extension>
        <mime-type>application/x-tar</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>tcl</extension>
        <mime-type>application/x-tcl</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>tex</extension>
        <mime-type>application/x-tex</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>texi</extension>
        <mime-type>application/x-texinfo</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>texinfo</extension>
        <mime-type>application/x-texinfo</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>tif</extension>
        <mime-type>image/tiff</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>tiff</extension>
        <mime-type>image/tiff</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>tr</extension>
        <mime-type>application/x-troff</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>tsv</extension>
        <mime-type>text/tab-separated-values</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>txt</extension>
        <mime-type>text/plain</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>ulw</extension>
        <mime-type>audio/basic</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>ustar</extension>
        <mime-type>application/x-ustar</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>xbm</extension>
        <mime-type>image/x-xbitmap</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>xht</extension>
        <mime-type>application/xhtml+xml</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>xhtml</extension>
        <mime-type>application/xhtml+xml</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>xml</extension>
        <mime-type>text/xml</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>xpm</extension>
        <mime-type>image/x-xpixmap</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>xsl</extension>
        <mime-type>text/xml</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>xwd</extension>
        <mime-type>image/x-xwindowdump</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>wav</extension>
        <mime-type>audio/x-wav</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>svg</extension>
        <mime-type>image/svg+xml</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>svgz</extension>
        <mime-type>image/svg+xml</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>vsd</extension>
        <mime-type>application/x-visio</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>wbmp</extension>
        <mime-type>image/vnd.wap.wbmp</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>wml</extension>
        <mime-type>text/vnd.wap.wml</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>wmlc</extension>
        <mime-type>application/vnd.wap.wmlc</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>wmls</extension>
        <mime-type>text/vnd.wap.wmlscript</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>wmlscriptc</extension>
        <mime-type>application/vnd.wap.wmlscriptc</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>wrl</extension>
        <mime-type>x-world/x-vrml</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>Z</extension>
        <mime-type>application/x-compress</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>z</extension>
        <mime-type>application/x-compress</mime-type>
    </mime-mapping>
    <mime-mapping>
        <extension>zip</extension>
        <mime-type>application/zip</mime-type>
    </mime-mapping>