1.常见的content type：

.aiff = audio/aiff
.anv = application/x-anv
.asa = text/asa
.asf = video/x-ms-asf
.asp = text/asp
.asx = video/x-ms-asf
.au = audio/basic
.avi = video/avi
.awf = application/vnd.adobe.workflow
.biz = text/xml
.bmp = application/x-bmp
.bot = application/x-bot
.c4t = application/x-c4t
.c90 = application/x-c90
.cal = application/x-cals
.cat = application/vnd.ms-pki.seccat
.cdf = application/x-netcdf
.cdr = application/x-cdr
.cel = application/x-cel
.cer = application/x-x509-ca-cert
.cg4 = application/x-g4
.cgm = application/x-cgm
.cit = application/x-cit
.class = java/*
.cml = text/xml :客户端浏览器按XML格式进行解析文档
.cmp = application/x-cmp
.cmx = application/x-cmx
.cot = application/x-cot
.crl = application/pkix-crl
.crt = application/x-x509-ca-cert
.csi = application/x-csi
.css = text/css :客户端浏览器按CSS格式进行解析文档
.cut = application/x-cut
.dbf = application/x-dbf
.dbm = application/x-dbm
.dbx = application/x-dbx
.dcd = text/xml :客户端浏览器按XML格式进行解析文档
.dcx = application/x-dcx
.der = application/x-x509-ca-cert
.dgn = application/x-dgn
.dib = application/x-dib
.dll = application/x-msdownload
.doc = application/msword
.dot = application/msword
.drw = application/x-drw
.dtd = text/xml :客户端浏览器按XML格式进行解析文档
.dwf = Model/vnd.dwf
.dwf = application/x-dwf
.dwg = application/x-dwg
.dxb = application/x-dxb
.dxf = application/x-dxf
.edn = application/vnd.adobe.edn
.emf = application/x-emf
.eml = message/rfc822
.ent = text/xml :客户端浏览器按XML格式进行解析文档
.epi = application/x-epi
.eps = application/x-ps
.eps = application/postscript
.etd = application/x-ebx
.exe = application/x-msdownload
.fax = image/fax
.fdf = application/vnd.fdf
.fif = application/fractals
.fo = text/xml :客户端浏览器按XML格式进行解析文档
.frm = application/x-frm
.g4 = application/x-g4
.gbr = application/x-gbr
.gcd = application/x-gcd
.gif = image/gif
.gl2 = application/x-gl2
.gp4 = application/x-gp4
.hgl = application/x-hgl
.hmr = application/x-hmr
.hpg = application/x-hpgl
.hpl = application/x-hpl
.hqx = application/mac-binhex40
.hrf = application/x-hrf
.hta = application/hta
.htc = text/x-component
.htm = text/html :客户端浏览器按超文本格式进行解析文档
.html = text/html :客户端浏览器按超文本格式进行解析文档
.htt = text/webviewhtml
.htx = text/html :客户端浏览器按超文本格式进行解析文档
.icb = application/x-icb
.ico = image/x-icon
.ico = application/x-ico
.iff = application/x-iff
.ig4 = application/x-g4
.igs = application/x-igs
.iii = application/x-iphone
.img = application/x-img
.ins = application/x-internet-signup
.isp = application/x-internet-signup
.IVF = video/x-ivf
.java = java/*
.jfif = image/jpeg
.jpe = image/jpeg
.jpe = application/x-jpe
.jpeg = image/jpeg
.jpg = image/jpeg
.jpg = application/x-jpg
.js = application/x-javascript
.jsp = text/html :客户端浏览器按超文本格式进行解析文档
.la1 = audio/x-liquid-file
.lar = application/x-laplayer-reg
.latex = application/x-latex
.lavs = audio/x-liquid-secure
.lbm = application/x-lbm
.lmsff = audio/x-la-lms
.ls = application/x-javascript
.ltr = application/x-ltr
.m1v = video/x-mpeg
.m2v = video/x-mpeg
.m3u = audio/mpegurl
.m4e = video/mpeg4
.mac = application/x-mac
.man = application/x-troff-man
.math = text/xml
.mdb = application/msaccess
.mdb = application/x-mdb
.mfp = application/x-shockwave-flash
.mht = message/rfc822
.mhtml = message/rfc822
.mi = application/x-mi
.mid = audio/mid
.midi = audio/mid
.mil = application/x-mil
.mml = text/xml
.mnd = audio/x-musicnet-download
.mns = audio/x-musicnet-stream
.mocha = application/x-javascript
.movie = video/x-sgi-movie
.mp1 = audio/mp1
.mp2 = audio/mp2
.mp2v = video/mpeg
.mp3 = audio/mp3
.mp4 = video/mpeg4
.mpa = video/x-mpg
.mpd = application/vnd.ms-project
.mpe = video/x-mpeg
.mpeg = video/mpg
.mpg = video/mpg
.mpga = audio/rn-mpeg
.mpp = application/vnd.ms-project
.mps = video/x-mpeg
.mpt = application/vnd.ms-project
.mpv = video/mpg
.mpv2 = video/mpeg
.mpw = application/vnd.ms-project
.mpx = application/vnd.ms-project
.mtx = text/xml
.mxp = application/x-mmxp
.net = image/pnetvue
.nrf = application/x-nrf
.nws = message/rfc822
.odc = text/x-ms-odc
.out = application/x-out
.p10 = application/pkcs10
.p12 = application/x-pkcs12
.p7b = application/x-pkcs7-certificates
.p7c = application/pkcs7-mime
.p7m = application/pkcs7-mime
.p7r = application/x-pkcs7-certreqresp
.p7s = application/pkcs7-signature
.pc5 = application/x-pc5
.pci = application/x-pci
.pcl = application/x-pcl
.pcx = application/x-pcx
.pdf = application/pdf :客户端浏览器按PDF格式进行解析文档
.pdf = application/pdf
.pdx = application/vnd.adobe.pdx
.pfx = application/x-pkcs12
.pgl = application/x-pgl
.pic = application/x-pic
.pko = application/vnd.ms-pki.pko
.pl = application/x-perl
.plg = text/html
.pls = audio/scpls
.plt = application/x-plt
.png = image/png
.png = application/x-png
.pot = application/vnd.ms-powerpoint
.ppa = application/vnd.ms-powerpoint
.ppm = application/x-ppm
.pps = application/vnd.ms-powerpoint
.ppt = application/vnd.ms-powerpoint
.ppt = application/x-ppt
.pr = application/x-pr
.prf = application/pics-rules
.prn = application/x-prn
.prt = application/x-prt
.ps = application/x-ps
.ps = application/postscript
.ptn = application/x-ptn
.pwz = application/vnd.ms-powerpoint
.r3t = text/vnd.rn-realtext3d
.ra = audio/vnd.rn-realaudio
.ram = audio/x-pn-realaudio
.ras = application/x-ras
.rat = application/rat-file
.rdf = text/xml
.rec = application/vnd.rn-recording
.red = application/x-red
.rgb = application/x-rgb
.rjs = application/vnd.rn-realsystem-rjs
.rjt = application/vnd.rn-realsystem-rjt
.rlc = application/x-rlc
.rle = application/x-rle
.rm = application/vnd.rn-realmedia
.rmf = application/vnd.adobe.rmf
.rmi = audio/mid
.rmj = application/vnd.rn-realsystem-rmj
.rmm = audio/x-pn-realaudio
.rmp = application/vnd.rn-rn_music_package
.rms = application/vnd.rn-realmedia-secure
.rmvb = application/vnd.rn-realmedia-vbr
.rmx = application/vnd.rn-realsystem-rmx
.rnx = application/vnd.rn-realplayer
.rp = image/vnd.rn-realpix
.rpm = audio/x-pn-realaudio-plugin
.rsml = application/vnd.rn-rsml
.rt = text/vnd.rn-realtext
.rtf = application/msword
.rtf = application/x-rtf
.rv = video/vnd.rn-realvideo
.sam = application/x-sam
.sat = application/x-sat
.sdp = application/sdp
.sdw = application/x-sdw
.sit = application/x-stuffit
.slb = application/x-slb
.sld = application/x-sld
.slk = drawing/x-slk
.smi = application/smil
.smil = application/smil
.smk = application/x-smk
.snd = audio/basic
.sol = text/plain
.sor = text/plain
.spc = application/x-pkcs7-certificates
.spl = application/futuresplash
.spp = text/xml
.ssm = application/streamingmedia
.sst = application/vnd.ms-pki.certstore
.stl = application/vnd.ms-pki.stl
.stm = text/html
.sty = application/x-sty
.svg = text/xml
.swf = application/x-shockwave-flash :客户端浏览器按 Flash 格式进行解析文档
.tdf = application/x-tdf
.tg4 = application/x-tg4
.tga = application/x-tga
.tif = image/tiff
.tif = application/x-tif
.tiff = image/tiff
.tld = text/xml
.top = drawing/x-top
.torrent = application/x-bittorrent
.tsd = text/xml
.txt = text/plain :客户端浏览器按 纯文本 格式进行解析文档
.uin = application/x-icq
.uls = text/iuls
.vcf = text/x-vcard
.vda = application/x-vda
.vdx = application/vnd.visio
.vml = text/xml
.vpg = application/x-vpeg005
.vsd = application/vnd.visio
.vsd = application/x-vsd
.vss = application/vnd.visio
.vst = application/vnd.visio
.vst = application/x-vst
.vsw = application/vnd.visio
.vsx = application/vnd.visio
.vtx = application/vnd.visio
.vxml = text/xml
.wav = audio/wav
.wax = audio/x-ms-wax
.wb1 = application/x-wb1
.wb2 = application/x-wb2
.wb3 = application/x-wb3
.wbmp = image/vnd.wap.wbmp
.wiz = application/msword
.wk3 = application/x-wk3
.wk4 = application/x-wk4
.wkq = application/x-wkq
.wks = application/x-wks
.wm = video/x-ms-wm
.wma = audio/x-ms-wma
.wmd = application/x-ms-wmd
.wmf = application/x-wmf
.wml = text/vnd.wap.wml
.wmv = video/x-ms-wmv
.wmx = video/x-ms-wmx
.wmz = application/x-ms-wmz
.wp6 = application/x-wp6
.wpd = application/x-wpd
.wpg = application/x-wpg
.wpl = application/vnd.ms-wpl
.wq1 = application/x-wq1
.wr1 = application/x-wr1
.wri = application/x-wri
.wrk = application/x-wrk
.ws = application/x-ws
.ws2 = application/x-ws
.wsc = text/scriptlet
.wsdl = text/xml
.wvx = video/x-ms-wvx
.xdp = application/vnd.adobe.xdp
.xdr = text/xml
.xfd = application/vnd.adobe.xfd
.xfdf = application/vnd.adobe.xfdf
.xhtml = text/html
.xls = application/vnd.ms-excel
.xls = application/x-xls
.xlw = application/x-xlw
.xml = text/xml
.xpl = audio/scpls
.xq = text/xml
.xql = text/xml
.xquery = text/xml
.xsd = text/xml
.xsl = text/xml
.xslt = text/xml
.xwd = application/x-xwd
.x_b = application/x-x_b
.x_t = application/x-x_t

2.利用python处理成switch语句分支

import io

file = open('content.txt')
text = ''

while(True):
    line = file.readline()
    words = line.split('=')
    if (len(words) > 1):
        w_cases = words[0].replace('.', '').replace(' ', '')
        w_retrun = words[1].replace(' ', '').replace('\n', '')
        text += 'case "' + w_cases + '":\r\nreturn "' + w_retrun + '";\r\n'
    if not line:
        break;

print(text)

file.close()

w_file = open(r't.txt', 'w')
w_file.write(text)
w_file.close()

3.生成getContentType方法

/**
 * 根据文件后缀设置 content type
 *
 * @param ext 需要小写
 * @return
 */
private String getContentType(String ext) {
    switch (ext) {
        case "aiff":
            return "audio/aiff";
        case "anv":
            return "application/x-anv";
        case "asa":
            return "text/asa";
        case "asf":
            return "video/x-ms-asf";
        case "asp":
            return "text/asp";
        case "asx":
            return "video/x-ms-asf";
        case "au":
            return "audio/basic";
        case "avi":
            return "video/avi";
        case "awf":
            return "application/vnd.adobe.workflow";
        case "biz":
            return "text/xml";
        case "bmp":
            return "application/x-bmp";
        case "bot":
            return "application/x-bot";
        case "c4t":
            return "application/x-c4t";
        case "c90":
            return "application/x-c90";
        case "cal":
            return "application/x-cals";
        case "cat":
            return "application/vnd.ms-pki.seccat";
        case "cdf":
            return "application/x-netcdf";
        case "cdr":
            return "application/x-cdr";
        case "cel":
            return "application/x-cel";
        case "cer":
            return "application/x-x509-ca-cert";
        case "cg4":
            return "application/x-g4";
        case "cgm":
            return "application/x-cgm";
        case "cit":
            return "application/x-cit";
        case "class":
            return "java/*";
        case "cml":
            return "text/xml:客户端浏览器按XML格式进行解析文档";
        case "cmp":
            return "application/x-cmp";
        case "cmx":
            return "application/x-cmx";
        case "cot":
            return "application/x-cot";
        case "crl":
            return "application/pkix-crl";
        case "crt":
            return "application/x-x509-ca-cert";
        case "csi":
            return "application/x-csi";
        case "css":
            return "text/css:客户端浏览器按CSS格式进行解析文档";
        case "cut":
            return "application/x-cut";
        case "dbf":
            return "application/x-dbf";
        case "dbm":
            return "application/x-dbm";
        case "dbx":
            return "application/x-dbx";
        case "dcd":
            return "text/xml:客户端浏览器按XML格式进行解析文档";
        case "dcx":
            return "application/x-dcx";
        case "der":
            return "application/x-x509-ca-cert";
        case "dgn":
            return "application/x-dgn";
        case "dib":
            return "application/x-dib";
        case "dll":
            return "application/x-msdownload";
        case "doc":
            return "application/msword";
        case "dot":
            return "application/msword";
        case "drw":
            return "application/x-drw";
        case "dtd":
            return "text/xml:客户端浏览器按XML格式进行解析文档";
        case "dwf":
            return "application/x-dwf";
        case "dwg":
            return "application/x-dwg";
        case "dxb":
            return "application/x-dxb";
        case "dxf":
            return "application/x-dxf";
        case "edn":
            return "application/vnd.adobe.edn";
        case "emf":
            return "application/x-emf";
        case "eml":
            return "message/rfc822";
        case "ent":
            return "text/xml:客户端浏览器按XML格式进行解析文档";
        case "epi":
            return "application/x-epi";
        case "eps":
            return "application/postscript";
        case "etd":
            return "application/x-ebx";
        case "exe":
            return "application/x-msdownload";
        case "fax":
            return "image/fax";
        case "fdf":
            return "application/vnd.fdf";
        case "fif":
            return "application/fractals";
        case "fo":
            return "text/xml:客户端浏览器按XML格式进行解析文档";
        case "frm":
            return "application/x-frm";
        case "g4":
            return "application/x-g4";
        case "gbr":
            return "application/x-gbr";
        case "gcd":
            return "application/x-gcd";
        case "gif":
            return "image/gif";
        case "gl2":
            return "application/x-gl2";
        case "gp4":
            return "application/x-gp4";
        case "hgl":
            return "application/x-hgl";
        case "hmr":
            return "application/x-hmr";
        case "hpg":
            return "application/x-hpgl";
        case "hpl":
            return "application/x-hpl";
        case "hqx":
            return "application/mac-binhex40";
        case "hrf":
            return "application/x-hrf";
        case "hta":
            return "application/hta";
        case "htc":
            return "text/x-component";
        case "htm":
            return "text/html:客户端浏览器按超文本格式进行解析文档";
        case "html":
            return "text/html:客户端浏览器按超文本格式进行解析文档";
        case "htt":
            return "text/webviewhtml";
        case "htx":
            return "text/html:客户端浏览器按超文本格式进行解析文档";
        case "icb":
            return "application/x-icb";
        case "ico":
            return "image/x-icon";
        case "iff":
            return "application/x-iff";
        case "ig4":
            return "application/x-g4";
        case "igs":
            return "application/x-igs";
        case "iii":
            return "application/x-iphone";
        case "img":
            return "application/x-img";
        case "ins":
            return "application/x-internet-signup";
        case "isp":
            return "application/x-internet-signup";
        case "IVF":
            return "video/x-ivf";
        case "java":
            return "java/*";
        case "jfif":
            return "image/jpeg";
        case "jpe":
            return "image/jpeg";
        case "jpeg":
            return "image/jpeg";
        case "jpg":
            return "image/jpeg";
        case "js":
            return "application/x-javascript";
        case "jsp":
            return "text/html:客户端浏览器按超文本格式进行解析文档";
        case "la1":
            return "audio/x-liquid-file";
        case "lar":
            return "application/x-laplayer-reg";
        case "latex":
            return "application/x-latex";
        case "lavs":
            return "audio/x-liquid-secure";
        case "lbm":
            return "application/x-lbm";
        case "lmsff":
            return "audio/x-la-lms";
        case "ls":
            return "application/x-javascript";
        case "ltr":
            return "application/x-ltr";
        case "m1v":
            return "video/x-mpeg";
        case "m2v":
            return "video/x-mpeg";
        case "m3u":
            return "audio/mpegurl";
        case "m4e":
            return "video/mpeg4";
        case "mac":
            return "application/x-mac";
        case "man":
            return "application/x-troff-man";
        case "math":
            return "text/xml";
        case "mdb":
            return "application/x-mdb";
        case "mfp":
            return "application/x-shockwave-flash";
        case "mht":
            return "message/rfc822";
        case "mhtml":
            return "message/rfc822";
        case "mi":
            return "application/x-mi";
        case "mid":
            return "audio/mid";
        case "midi":
            return "audio/mid";
        case "mil":
            return "application/x-mil";
        case "mml":
            return "text/xml";
        case "mnd":
            return "audio/x-musicnet-download";
        case "mns":
            return "audio/x-musicnet-stream";
        case "mocha":
            return "application/x-javascript";
        case "movie":
            return "video/x-sgi-movie";
        case "mp1":
            return "audio/mp1";
        case "mp2":
            return "audio/mp2";
        case "mp2v":
            return "video/mpeg";
        case "mp3":
            return "audio/mp3";
        case "mp4":
            return "video/mpeg4";
        case "mpa":
            return "video/x-mpg";
        case "mpd":
            return "application/vnd.ms-project";
        case "mpe":
            return "video/x-mpeg";
        case "mpeg":
            return "video/mpg";
        case "mpg":
            return "video/mpg";
        case "mpga":
            return "audio/rn-mpeg";
        case "mpp":
            return "application/vnd.ms-project";
        case "mps":
            return "video/x-mpeg";
        case "mpt":
            return "application/vnd.ms-project";
        case "mpv":
            return "video/mpg";
        case "mpv2":
            return "video/mpeg";
        case "mpw":
            return "application/vnd.ms-project";
        case "mpx":
            return "application/vnd.ms-project";
        case "mtx":
            return "text/xml";
        case "mxp":
            return "application/x-mmxp";
        case "net":
            return "image/pnetvue";
        case "nrf":
            return "application/x-nrf";
        case "nws":
            return "message/rfc822";
        case "odc":
            return "text/x-ms-odc";
        case "out":
            return "application/x-out";
        case "p10":
            return "application/pkcs10";
        case "p12":
            return "application/x-pkcs12";
        case "p7b":
            return "application/x-pkcs7-certificates";
        case "p7c":
            return "application/pkcs7-mime";
        case "p7m":
            return "application/pkcs7-mime";
        case "p7r":
            return "application/x-pkcs7-certreqresp";
        case "p7s":
            return "application/pkcs7-signature";
        case "pc5":
            return "application/x-pc5";
        case "pci":
            return "application/x-pci";
        case "pcl":
            return "application/x-pcl";
        case "pcx":
            return "application/x-pcx";
        case "pdf":
            return "application/pdf";
        case "pdx":
            return "application/vnd.adobe.pdx";
        case "pfx":
            return "application/x-pkcs12";
        case "pgl":
            return "application/x-pgl";
        case "pic":
            return "application/x-pic";
        case "pko":
            return "application/vnd.ms-pki.pko";
        case "pl":
            return "application/x-perl";
        case "plg":
            return "text/html";
        case "pls":
            return "audio/scpls";
        case "plt":
            return "application/x-plt";
        case "png":
            return "image/png";
        case "pot":
            return "application/vnd.ms-powerpoint";
        case "ppa":
            return "application/vnd.ms-powerpoint";
        case "ppm":
            return "application/x-ppm";
        case "pps":
            return "application/vnd.ms-powerpoint";
        case "ppt":
            return "application/x-ppt";
        case "pr":
            return "application/x-pr";
        case "prf":
            return "application/pics-rules";
        case "prn":
            return "application/x-prn";
        case "prt":
            return "application/x-prt";
        case "ps":
            return "application/x-ps";
        case "ptn":
            return "application/x-ptn";
        case "pwz":
            return "application/vnd.ms-powerpoint";
        case "r3t":
            return "text/vnd.rn-realtext3d";
        case "ra":
            return "audio/vnd.rn-realaudio";
        case "ram":
            return "audio/x-pn-realaudio";
        case "ras":
            return "application/x-ras";
        case "rat":
            return "application/rat-file";
        case "rdf":
            return "text/xml";
        case "rec":
            return "application/vnd.rn-recording";
        case "red":
            return "application/x-red";
        case "rgb":
            return "application/x-rgb";
        case "rjs":
            return "application/vnd.rn-realsystem-rjs";
        case "rjt":
            return "application/vnd.rn-realsystem-rjt";
        case "rlc":
            return "application/x-rlc";
        case "rle":
            return "application/x-rle";
        case "rm":
            return "application/vnd.rn-realmedia";
        case "rmf":
            return "application/vnd.adobe.rmf";
        case "rmi":
            return "audio/mid";
        case "rmj":
            return "application/vnd.rn-realsystem-rmj";
        case "rmm":
            return "audio/x-pn-realaudio";
        case "rmp":
            return "application/vnd.rn-rn_music_package";
        case "rms":
            return "application/vnd.rn-realmedia-secure";
        case "rmvb":
            return "application/vnd.rn-realmedia-vbr";
        case "rmx":
            return "application/vnd.rn-realsystem-rmx";
        case "rnx":
            return "application/vnd.rn-realplayer";
        case "rp":
            return "image/vnd.rn-realpix";
        case "rpm":
            return "audio/x-pn-realaudio-plugin";
        case "rsml":
            return "application/vnd.rn-rsml";
        case "rt":
            return "text/vnd.rn-realtext";
        case "rtf":
            return "application/x-rtf";
        case "rv":
            return "video/vnd.rn-realvideo";
        case "sam":
            return "application/x-sam";
        case "sat":
            return "application/x-sat";
        case "sdp":
            return "application/sdp";
        case "sdw":
            return "application/x-sdw";
        case "sit":
            return "application/x-stuffit";
        case "slb":
            return "application/x-slb";
        case "sld":
            return "application/x-sld";
        case "slk":
            return "drawing/x-slk";
        case "smi":
            return "application/smil";
        case "smil":
            return "application/smil";
        case "smk":
            return "application/x-smk";
        case "snd":
            return "audio/basic";
        case "sol":
            return "text/plain";
        case "sor":
            return "text/plain";
        case "spc":
            return "application/x-pkcs7-certificates";
        case "spl":
            return "application/futuresplash";
        case "spp":
            return "text/xml";
        case "ssm":
            return "application/streamingmedia";
        case "sst":
            return "application/vnd.ms-pki.certstore";
        case "stl":
            return "application/vnd.ms-pki.stl";
        case "stm":
            return "text/html";
        case "sty":
            return "application/x-sty";
        case "svg":
            return "text/xml";
        case "swf":
            return "application/x-shockwave-flash:客户端浏览器按Flash格式进行解析文档";
        case "tdf":
            return "application/x-tdf";
        case "tg4":
            return "application/x-tg4";
        case "tga":
            return "application/x-tga";
        case "tif":
            return "image/tiff";
        case "tiff":
            return "image/tiff";
        case "tld":
            return "text/xml";
        case "top":
            return "drawing/x-top";
        case "torrent":
            return "application/x-bittorrent";
        case "tsd":
            return "text/xml";
        case "txt":
            return "text/plain:客户端浏览器按纯文本格式进行解析文档";
        case "uin":
            return "application/x-icq";
        case "uls":
            return "text/iuls";
        case "vcf":
            return "text/x-vcard";
        case "vda":
            return "application/x-vda";
        case "vdx":
            return "application/vnd.visio";
        case "vml":
            return "text/xml";
        case "vpg":
            return "application/x-vpeg005";
        case "vsd":
            return "application/x-vsd";
        case "vss":
            return "application/vnd.visio";
        case "vst":
            return "application/x-vst";
        case "vsw":
            return "application/vnd.visio";
        case "vsx":
            return "application/vnd.visio";
        case "vtx":
            return "application/vnd.visio";
        case "vxml":
            return "text/xml";
        case "wav":
            return "audio/wav";
        case "wax":
            return "audio/x-ms-wax";
        case "wb1":
            return "application/x-wb1";
        case "wb2":
            return "application/x-wb2";
        case "wb3":
            return "application/x-wb3";
        case "wbmp":
            return "image/vnd.wap.wbmp";
        case "wiz":
            return "application/msword";
        case "wk3":
            return "application/x-wk3";
        case "wk4":
            return "application/x-wk4";
        case "wkq":
            return "application/x-wkq";
        case "wks":
            return "application/x-wks";
        case "wm":
            return "video/x-ms-wm";
        case "wma":
            return "audio/x-ms-wma";
        case "wmd":
            return "application/x-ms-wmd";
        case "wmf":
            return "application/x-wmf";
        case "wml":
            return "text/vnd.wap.wml";
        case "wmv":
            return "video/x-ms-wmv";
        case "wmx":
            return "video/x-ms-wmx";
        case "wmz":
            return "application/x-ms-wmz";
        case "wp6":
            return "application/x-wp6";
        case "wpd":
            return "application/x-wpd";
        case "wpg":
            return "application/x-wpg";
        case "wpl":
            return "application/vnd.ms-wpl";
        case "wq1":
            return "application/x-wq1";
        case "wr1":
            return "application/x-wr1";
        case "wri":
            return "application/x-wri";
        case "wrk":
            return "application/x-wrk";
        case "ws":
            return "application/x-ws";
        case "ws2":
            return "application/x-ws";
        case "wsc":
            return "text/scriptlet";
        case "wsdl":
            return "text/xml";
        case "wvx":
            return "video/x-ms-wvx";
        case "xdp":
            return "application/vnd.adobe.xdp";
        case "xdr":
            return "text/xml";
        case "xfd":
            return "application/vnd.adobe.xfd";
        case "xfdf":
            return "application/vnd.adobe.xfdf";
        case "xhtml":
            return "text/html";
        case "xls":
            return "application/x-xls";
        case "xlw":
            return "application/x-xlw";
        case "xml":
            return "text/xml";
        case "xpl":
            return "audio/scpls";
        case "xq":
            return "text/xml";
        case "xql":
            return "text/xml";
        case "xquery":
            return "text/xml";
        case "xsd":
            return "text/xml";
        case "xsl":
            return "text/xml";
        case "xslt":
            return "text/xml";
        case "xwd":
            return "application/x-xwd";
        case "x_b":
            return "application/x-x_b";
        case "x_t":
            return "application/x-x_t";
        default:
            return "application/octet-stream";
    }
}