Response.setContentType(MIME)的作用是时客户端的浏览器区分不同种类的数据，并根据不同的MIME调用浏览器内不同的程序嵌入模块来处理相应的数据。
MIME的作用：
由于MIME类型与文档的后缀相关，因此服务器使用文档的后缀来区分不同文件的MIME类型，服务器中必须定义文档后缀和MIME类型之间的对应关系。而客户程序从服务器上接收数据的时候，它只是从服务器接受数据流，并不了解文档的名字，因此服务器必须使用附加信息来告诉客户程序数据的MIME类型。服务器在发送真正的数据之前，就要先发送标志数据的MIME类型的信息，这个信息使用Content-type关键字进行定义，例如对于HTML文档，服务器将首先发送以下两行MIME标识信息,这个标识并不是真正的数据文件的一部分。
Content-type:text/html
注意，第二行为一个空行，这是必须的，使用这个空行的目的是将MIME信息与真正的数据内容分隔开。
MIME信息头有：
MIME-Version:
Content-Type:(常用。 该实体头的作用是让服务器告诉浏览器它发送的数据属于什么文件类型。)
Content-Transfer-Encoding:
Content-ID:
Content-Disposition: (常用。 当Content-Type 的类型为要下载的类型时 , 这个信息头会告诉浏览器这个文件的名字和类型。参考www.wityx.com)
一般在Servlet中，我们会首先设置请求以及响应的内容类型和编码方式：
response.setContentType(“text/html;charset=UTF-8”);
response.setCharacterEncoding(“UTF-8”);
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类型大全
格式前面为后辍名，后面为对应的MIME型。
{".323", "text/h323" }, {".3gp", "video/3gpp" }, {".aab", "application/x-authoware-bin" }, {".aam", "application/x-authoware-map" }, {".aas", "application/x-authoware-seg" }, {".acx", "application/internet-property-stream" }, {".ai", "application/postscript" }, {".aif", "audio/x-aiff" }, {".aifc", "audio/x-aiff" }, {".aiff", "audio/x-aiff" }, {".als", "audio/X-Alpha5" }, {".amc", "application/x-mpeg" }, {".ani", "application/octet-stream" }, {".apk", "application/vnd.android.package-archive" }, {".asc", "text/plain" }, {".asd", "application/astound" }, {".asf", "video/x-ms-asf" }, {".asn", "application/astound" }, {".asp", "application/x-asap" }, {".asr", "video/x-ms-asf" }, {".asx", "video/x-ms-asf" }, {".au", "audio/basic" }, {".avb", "application/octet-stream" }, {".avi", "video/x-msvideo" }, {".awb", "audio/amr-wb" }, {".axs", "application/olescript" }, {".bas", "text/plain" }, {".bcpio", "application/x-bcpio" }, { ".bin", "application/octet-stream" }, {".bld", "application/bld" }, {".bld2", "application/bld2" }, {".bmp", "image/bmp" }, {".bpk", "application/octet-stream" }, {".bz2", "application/x-bzip2" }, {".c", "text/plain" }, {".cal", "image/x-cals" }, {".cat", "application/vnd.ms-pkiseccat" }, {".ccn", "application/x-cnc" }, {".cco", "application/x-cocoa" }, {".cdf", "application/x-cdf" }, {".cer", "application/x-x509-ca-cert" }, {".cgi", "magnus-internal/cgi" }, {".chat", "application/x-chat" }, {".class", "application/octet-stream" }, {".clp", "application/x-msclip" }, {".cmx", "image/x-cmx" }, {".co", "application/x-cult3d-object" }, {".cod", "image/cis-cod" }, {".conf", "text/plain" }, {".cpio", "application/x-cpio" }, {".cpp", "text/plain" }, {".cpt", "application/mac-compactpro" }, {".crd", "application/x-mscardfile" }, {".crl", "application/pkix-crl" }, {".crt", "application/x-x509-ca-cert" }, {".csh", "application/x-csh" }, {".csm", "chemical/x-csml" }, { ".csml","chemical/x-csml" }, {".css", "text/css" }, {".cur", "application/octet-stream" }, {".dcm", "x-lml/x-evm" }, {".dcr", "application/x-director" }, {".dcx", "image/x-dcx" }, {".der", "application/x-x509-ca-cert" }, {".dhtml", "text/html" }, { ".dir","application/x-director" }, {".dll", "application/x-msdownload" }, {".dmg", "application/octet-stream" }, {".dms", "application/octet-stream" }, {".doc", "application/msword" }, {".docx","application/vnd.openxmlformats-officedocument.wordprocessingml.document"}, {".dot", "application/msword" }, {".dvi", "application/x-dvi" }, {".dwf", "drawing/x-dwf" }, {".dwg", "application/x-autocad" }, {".dxf", "application/x-autocad" }, {".dxr", "application/x-director" }, {".ebk", "application/x-expandedbook" }, {".emb", "chemical/x-embl-dl-nucleotide" }, {".embl", "chemical/x-embl-dl-nucleotide" }, {".eps", "application/postscript" }, {".epub", "application/epub+zip" }, {".eri", "image/x-eri" }, {".es", "audio/echospeech" }, {".esl", "audio/echospeech" }, {".etc", "application/x-earthtime" }, {".etx", "text/x-setext" }, {".evm", "x-lml/x-evm" }, {".evy", "application/envoy" }, {".exe", "application/octet-stream" }, {".fh4", "image/x-freehand" }, {".fh5", "image/x-freehand" }, {".fhc", "image/x-freehand" }, {".fif", "application/fractals" }, {".flr", "x-world/x-vrml" }, {".flv", "flv-application/octet-stream" }, {".fm", "application/x-maker" }, {".fpx", "image/x-fpx" }, {".fvi", "video/isivideo" }, {".gau", "chemical/x-gaussian-input" }, {".gca", "application/x-gca-compressed" }, {".gdb", "x-lml/x-gdb" }, {".gif", "image/gif" }, {".gps", "application/x-gps" }, {".gtar", "application/x-gtar" }, {".gz", "application/x-gzip" }, {".h", "text/plain" }, {".hdf", "application/x-hdf" }, {".hdm", "text/x-hdml" }, {".hdml", "text/x-hdml" }, {".hlp", "application/winhlp" }, {".hqx", "application/mac-binhex40" }, {".hta", "application/hta" }, {".htc", "text/x-component" }, {".htm", "text/html" }, {".html", "text/html" }, { ".hts","text/html" }, {".htt", "text/webviewhtml" }, {".ice", "x-conference/x-cooltalk" }, {".ico", "image/x-icon" }, {".ief", "image/ief" }, {".ifm", "image/gif" }, {".ifs", "image/ifs" }, {".iii", "application/x-iphone" }, {".imy", "audio/melody" }, {".ins", "application/x-internet-signup" }, {".ips", "application/x-ipscript" }, {".ipx", "application/x-ipix" }, {".isp", "application/x-internet-signup" }, {".it", "audio/x-mod" }, {".itz", "audio/x-mod" }, {".ivr", "i-world/i-vrml" }, {".j2k", "image/j2k" }, {".jad", "text/vnd.sun.j2me.app-descriptor" }, {".jam", "application/x-jam" }, {".jar", "application/java-archive" }, {".java", "text/plain" }, {".jfif", "image/pipeg" }, {".jnlp", "application/x-java-jnlp-file" }, {".jpe", "image/jpeg" }, {".jpeg", "image/jpeg" }, {".jpg", "image/jpeg" }, {".jpz", "image/jpeg" }, {".js", "application/x-javascript" }, {".jwc", "application/jwc" }, {".kjx", "application/x-kjx" }, {".lak", "x-lml/x-lak" }, {".latex", "application/x-latex" }, { ".lcc","application/fastman" }, {".lcl", "application/x-digitalloca" }, {".lcr", "application/x-digitalloca" }, {".lgh", "application/lgh" }, {".lha", "application/octet-stream" }, {".lml", "x-lml/x-lml" }, {".lmlpack", "x-lml/x-lmlpack" }, {".log", "text/plain" }, {".lsf", "video/x-la-asf" }, {".lsx", "video/x-la-asf" }, {".lzh", "application/octet-stream" }, {".m13", "application/x-msmediaview" }, {".m14", "application/x-msmediaview" }, {".m15", "audio/x-mod" }, {".m3u", "audio/x-mpegurl" }, {".m3url", "audio/x-mpegurl" }, {".m4a", "audio/mp4a-latm" }, {".m4b", "audio/mp4a-latm" }, {".m4p", "audio/mp4a-latm" }, {".m4u", "video/vnd.mpegurl" }, {".m4v", "video/x-m4v" }, {".ma1", "audio/ma1" }, {".ma2", "audio/ma2" }, {".ma3", "audio/ma3" }, {".ma5", "audio/ma5" }, {".man", "application/x-troff-man" }, {".map", "magnus-internal/imagemap" }, {".mbd", "application/mbedlet" }, {".mct", "application/x-mascot" }, {".mdb", "application/x-msaccess" }, {".mdz", "audio/x-mod" }, {".me", "application/x-troff-me" }, {".mel", "text/x-vmel" }, {".mht", "message/rfc822" }, {".mhtml", "message/rfc822" }, {".mi", "application/x-mif" }, {".mid", "audio/mid" }, {".midi", "audio/midi" }, {".mif", "application/x-mif" }, {".mil", "image/x-cals" }, {".mio", "audio/x-mio" }, {".mmf", "application/x-skt-lbs" }, {".mng", "video/x-mng" }, {".mny", "application/x-msmoney" }, {".moc", "application/x-mocha" }, {".mocha", "application/x-mocha" }, {".mod", "audio/x-mod" }, {".mof", "application/x-yumekara" }, {".mol", "chemical/x-mdl-molfile" }, {".mop", "chemical/x-mopac-input" }, {".mov", "video/quicktime" }, {".movie", "video/x-sgi-movie" }, {".mp2", "video/mpeg" }, {".mp3", "audio/mpeg" }, {".mp4", "video/mp4" }, {".mpa", "video/mpeg" }, {".mpc", "application/vnd.mpohun.certificate" }, {".mpe", "video/mpeg" }, {".mpeg", "video/mpeg" }, {".mpg", "video/mpeg" }, {".mpg4", "video/mp4" }, {".mpga", "audio/mpeg" }, {".mpn", "application/vnd.mophun.application" }, {".mpp", "application/vnd.ms-project" }, {".mps", "application/x-mapserver" }, {".mpv2", "video/mpeg" }, {".mrl", "text/x-mrml" }, {".mrm", "application/x-mrm" }, {".ms", "application/x-troff-ms" }, {".msg", "application/vnd.ms-outlook" }, {".mts", "application/metastream" }, {".mtx", "application/metastream" }, {".mtz", "application/metastream" }, {".mvb", "application/x-msmediaview" }, {".mzv", "application/metastream" }, {".nar", "application/zip" }, {".nbmp", "image/nbmp" }, {".nc", "application/x-netcdf" }, { ".ndb","x-lml/x-ndb" }, {".ndwn", "application/ndwn" }, {".nif", "application/x-nif" }, {".nmz", "application/x-scream" }, {".nokia-op-logo", "image/vnd.nok-oplogo-color" }, {".npx", "application/x-netfpx" }, {".nsnd", "audio/nsnd" }, {".nva", "application/x-neva1" }, {".nws", "message/rfc822" }, {".oda", "application/oda" }, {".ogg", "audio/ogg" }, {".oom", "application/x-AtlasMate-Plugin" }, {".p10", "application/pkcs10" }, {".p12", "application/x-pkcs12" }, {".p7b", "application/x-pkcs7-certificates" }, {".p7c", "application/x-pkcs7-mime" }, {".p7m", "application/x-pkcs7-mime" }, {".p7r", "application/x-pkcs7-certreqresp" }, {".p7s", "application/x-pkcs7-signature" }, {".pac", "audio/x-pac" }, {".pae", "audio/x-epac" }, {".pan", "application/x-pan" }, {".pbm", "image/x-portable-bitmap" }, {".pcx", "image/x-pcx" }, {".pda", "image/x-pda" }, {".pdb", "chemical/x-pdb" }, {".pdf", "application/pdf" }, {".pfr", "application/font-tdpfr" }, {".pfx", "application/x-pkcs12" }, {".pgm", "image/x-portable-graymap" }, {".pict", "image/x-pict" }, {".pko", "application/ynd.ms-pkipko" }, {".pm", "application/x-perl" }, {".pma", "application/x-perfmon" }, {".pmc", "application/x-perfmon" }, {".pmd", "application/x-pmd" }, {".pml", "application/x-perfmon" }, {".pmr", "application/x-perfmon" }, {".pmw", "application/x-perfmon" }, {".png", "image/png" }, {".pnm", "image/x-portable-anymap" }, {".pnz", "image/png" }, {".pot,", "application/vnd.ms-powerpoint" }, {".ppm", "image/x-portable-pixmap" }, {".pps", "application/vnd.ms-powerpoint" }, {".ppt", "application/vnd.ms-powerpoint" }, {".pptx","application/vnd.openxmlformats-officedocument.presentationml.presentation"}, {".pqf", "application/x-cprplayer" }, {".pqi", "application/cprplayer" }, {".prc", "application/x-prc" }, {".prf", "application/pics-rules" }, {".prop", "text/plain" }, {".proxy", "application/x-ns-proxy-autoconfig" }, {".ps", "application/postscript" }, {".ptlk", "application/listenup" }, {".pub", "application/x-mspublisher" }, {".pvx", "video/x-pv-pvx" }, {".qcp", "audio/vnd.qcelp" }, {".qt", "video/quicktime" }, {".qti", "image/x-quicktime" }, {".qtif", "image/x-quicktime" }, {".r3t", "text/vnd.rn-realtext3d" }, {".ra", "audio/x-pn-realaudio" }, { ".ram","audio/x-pn-realaudio" }, {".rar", "application/octet-stream" }, {".ras", "image/x-cmu-raster" }, {".rc", "text/plain" }, {".rdf", "application/rdf+xml" }, {".rf", "image/vnd.rn-realflash" }, {".rgb", "image/x-rgb" }, {".rlf", "application/x-richlink" }, {".rm", "audio/x-pn-realaudio" }, {".rmf", "audio/x-rmf" }, {".rmi", "audio/mid" }, {".rmm", "audio/x-pn-realaudio" }, {".rmvb", "audio/x-pn-realaudio" }, {".rnx", "application/vnd.rn-realplayer" }, {".roff", "application/x-troff" }, { ".rp","image/vnd.rn-realpix" }, {".rpm", "audio/x-pn-realaudio-plugin" }, {".rt", "text/vnd.rn-realtext" }, {".rte", "x-lml/x-gps" }, {".rtf", "application/rtf" }, {".rtg", "application/metastream" }, {".rtx", "text/richtext" }, {".rv", "video/vnd.rn-realvideo" }, {".rwc", "application/x-rogerwilco" }, {".s3m", "audio/x-mod" }, {".s3z", "audio/x-mod" }, {".sca", "application/x-supercard" }, {".scd", "application/x-msschedule" }, {".sct", "text/scriptlet" }, {".sdf", "application/e-score" }, {".sea", "application/x-stuffit" }, {".setpay", "application/set-payment-initiation" }, {".setreg", "application/set-registration-initiation" }, {".sgm", "text/x-sgml" }, {".sgml", "text/x-sgml" }, {".sh", "application/x-sh" }, {".shar", "application/x-shar" }, {".shtml", "magnus-internal/parsed-html" }, {".shw", "application/presentations" }, {".si6", "image/si6" }, {".si7", "image/vnd.stiwap.sis" }, {".si9", "image/vnd.lgtwap.sis" }, {".sis", "application/vnd.symbian.install" }, {".sit", "application/x-stuffit" }, {".skd", "application/x-Koan" }, {".skm", "application/x-Koan" }, {".skp", "application/x-Koan" }, {".skt", "application/x-Koan" }, {".slc", "application/x-salsa" }, {".smd", "audio/x-smd" }, {".smi", "application/smil" }, { ".smil","application/smil" }, {".smp", "application/studiom" }, {".smz", "audio/x-smd" }, {".snd", "audio/basic" }, {".spc", "application/x-pkcs7-certificates" }, {".spl", "application/futuresplash" }, {".spr", "application/x-sprite" }, {".sprite", "application/x-sprite" }, {".sdp", "application/sdp" }, {".spt", "application/x-spt" }, {".src", "application/x-wais-source" }, {".sst", "application/vnd.ms-pkicertstore" }, {".stk", "application/hyperstudio" }, {".stl", "application/vnd.ms-pkistl" }, {".stm", "text/html" }, {".svg", "image/svg+xml" }, {".sv4cpio", "application/x-sv4cpio" }, {".sv4crc", "application/x-sv4crc" }, {".svf", "image/vnd" }, {".svg", "image/svg+xml" }, {".svh", "image/svh" }, {".svr", "x-world/x-svr" }, {".swf", "application/x-shockwave-flash" }, {".swfl", "application/x-shockwave-flash" }, {".t", "application/x-troff" }, {".tad", "application/octet-stream" }, {".talk", "text/x-speech" }, {".tar", "application/x-tar" }, {".taz", "application/x-tar" }, {".tbp", "application/x-timbuktu" }, {".tbt", "application/x-timbuktu" }, {".tcl", "application/x-tcl" }, {".tex", "application/x-tex" }, {".texi", "application/x-texinfo" }, {".texinfo", "application/x-texinfo" }, {".tgz", "application/x-compressed" }, { ".thm","application/vnd.eri.thm" }, {".tif", "image/tiff" }, {".tiff", "image/tiff" }, {".tki", "application/x-tkined" }, {".tkined", "application/x-tkined" }, {".toc", "application/toc" }, {".toy", "image/toy" }, {".tr", "application/x-troff" }, { ".trk","x-lml/x-gps" }, {".trm", "application/x-msterminal" }, {".tsi", "audio/tsplayer" }, {".tsp", "application/dsptype" }, {".tsv", "text/tab-separated-values" }, {".ttf", "application/octet-stream" }, {".ttz", "application/t-time" }, {".txt", "text/plain" }, {".uls", "text/iuls" }, {".ult", "audio/x-mod" }, {".ustar", "application/x-ustar" }, {".uu", "application/x-uuencode" }, {".uue", "application/x-uuencode" }, {".vcd", "application/x-cdlink" }, {".vcf", "text/x-vcard" }, {".vdo", "video/vdo" }, {".vib", "audio/vib" }, {".viv", "video/vivo" }, {".vivo", "video/vivo" }, {".vmd", "application/vocaltec-media-desc" }, {".vmf", "application/vocaltec-media-file" }, {".vmi", "application/x-dreamcast-vms-info" }, {".vms", "application/x-dreamcast-vms" }, {".vox", "audio/voxware" }, {".vqe", "audio/x-twinvq-plugin" }, {".vqf", "audio/x-twinvq" }, {".vql", "audio/x-twinvq" }, {".vre", "x-world/x-vream" }, {".vrml", "x-world/x-vrml" }, {".vrt", "x-world/x-vrt" }, {".vrw", "x-world/x-vream" }, {".vts", "workbook/formulaone" }, {".wav", "audio/x-wav" }, {".wax", "audio/x-ms-wax" }, {".wbmp", "image/vnd.wap.wbmp" }, {".wcm", "application/vnd.ms-works" }, {".wdb", "application/vnd.ms-works" }, {".web", "application/vnd.xara" }, { ".wi","image/wavelet" }, {".wis", "application/x-InstallShield" }, {".wks", "application/vnd.ms-works" }, {".wm", "video/x-ms-wm" }, {".wma", "audio/x-ms-wma" }, {".wmd", "application/x-ms-wmd" }, {".wmf", "application/x-msmetafile" }, {".wml", "text/vnd.wap.wml" }, {".wmlc", "application/vnd.wap.wmlc" }, {".wmls", "text/vnd.wap.wmlscript" }, {".wmlsc", "application/vnd.wap.wmlscriptc" }, {".wmlscript", "text/vnd.wap.wmlscript" }, {".wmv", "audio/x-ms-wmv" }, {".wmx", "video/x-ms-wmx" }, { ".wmz","application/x-ms-wmz" }, {".wpng", "image/x-up-wpng" }, {".wps", "application/vnd.ms-works" }, {".wpt", "x-lml/x-gps" }, {".wri", "application/x-mswrite" }, {".wrl", "x-world/x-vrml" }, {".wrz", "x-world/x-vrml" }, {".ws", "text/vnd.wap.wmlscript" }, {".wsc", "application/vnd.wap.wmlscriptc" }, {".wv", "video/wavelet" }, {".wvx", "video/x-ms-wvx" }, {".wxl", "application/x-wxl" }, {".x-gzip", "application/x-gzip" }, {".xaf", "x-world/x-vrml" }, {".xar", "application/vnd.xara" }, {".xbm", "image/x-xbitmap" }, {".xdm", "application/x-xdma" }, {".xdma", "application/x-xdma" }, {".xdw", "application/vnd.fujixerox.docuworks" }, {".xht", "application/xhtml+xml" }, {".xhtm", "application/xhtml+xml" }, {".xhtml", "application/xhtml+xml" }, {".xla", "application/vnd.ms-excel" }, {".xlc", "application/vnd.ms-excel" }, {".xll", "application/x-excel" }, {".xlm", "application/vnd.ms-excel" }, {".xls", "application/vnd.ms-excel" }, {".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"}, {".xlt", "application/vnd.ms-excel" }, {".xlw", "application/vnd.ms-excel" }, {".xm", "audio/x-mod" }, {".xml","text/plain"}, {".xml","application/xml"},[1] {".xmz", "audio/x-mod" }, {".xof", "x-world/x-vrml" }, {".xpi", "application/x-xpinstall" }, {".xpm", "image/x-xpixmap" }, {".xsit", "text/xml" }, {".xsl", "text/xml" }, {".xul", "text/xul" }, {".xwd", "image/x-xwindowdump" }, {".xyz", "chemical/x-pdb" }, {".yz1", "application/x-yz1" }, {".z", "application/x-compress" },[1] {".zac", "application/x-zaurus-zac" }, {".zip", "application/zip" }, {".json", "application/json" },
