Java 如何获取Multipart文件的真实扩展名类型
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时间：2020-08-11 14:27:46 来源:igfitidea点击:
How to get the real extension type of Multipart file
提问by Vipul Jain
I have checked answer here, but here first they are saving it to some place and then reading it's stream and trying to check Mime type of that file
我在这里检查了答案，但首先他们将它保存到某个地方，然后读取它的流并尝试检查该文件的 Mime 类型
Get real file extension -Java code
But I want to know the file type before even saving it to the hard disk or at some place.
但我想在将文件保存到硬盘或某个地方之前知道文件类型。
I know I can do it in these 2 more ways
我知道我可以通过另外两种方式做到这一点
File savedFile = new File(fileHandler.createTodayFolder(fileLocation) + "/" + name);
Path path = Paths.get(file.get);
Tika tika = new Tika();
String checkType = tika.detect(path.toFile());
and
和
Path path = Paths.get(savedFile.getPath());
Files.probeContentType(path)
But in these both cases they are using somefile which is already at some location in hard disk. I want code something like this
但是在这两种情况下，他们都使用了一些已经在硬盘某个位置的文件。我想要这样的代码
public @ResponseBody ResponseEntity<?> importResume(@RequestParam(value = "name", required = false) String name,
@RequestParam("file") MultipartFile file) {
if (file!=DESIRED_TYPE)
{
return Exception;
}
}
Is there any way of doing this ???
有没有办法做到这一点？？？
回答by inigoD
You can map the mimetype to a existing extension by making a map...
您可以通过制作地图将 mimetype 映射到现有扩展...
You can use apache.mime.types for create one like it's done here:
您可以使用 apache.mime.types 来创建一个，就像在这里完成的一样：
public class MimeTypes {
public static final String MIME_APPLICATION_ANDREW_INSET = "application/andrew-inset";
public static final String MIME_APPLICATION_JSON = "application/json";
public static final String MIME_APPLICATION_ZIP = "application/zip";
public static final String MIME_APPLICATION_X_GZIP = "application/x-gzip";
public static final String MIME_APPLICATION_TGZ = "application/tgz";
public static final String MIME_APPLICATION_MSWORD = "application/msword";
public static final String MIME_APPLICATION_POSTSCRIPT = "application/postscript";
public static final String MIME_APPLICATION_PDF = "application/pdf";
public static final String MIME_APPLICATION_JNLP = "application/jnlp";
public static final String MIME_APPLICATION_MAC_BINHEX40 = "application/mac-binhex40";
public static final String MIME_APPLICATION_MAC_COMPACTPRO = "application/mac-compactpro";
public static final String MIME_APPLICATION_MATHML_XML = "application/mathml+xml";
public static final String MIME_APPLICATION_OCTET_STREAM = "application/octet-stream";
public static final String MIME_APPLICATION_ODA = "application/oda";
public static final String MIME_APPLICATION_RDF_XML = "application/rdf+xml";
public static final String MIME_APPLICATION_JAVA_ARCHIVE = "application/java-archive";
public static final String MIME_APPLICATION_RDF_SMIL = "application/smil";
public static final String MIME_APPLICATION_SRGS = "application/srgs";
public static final String MIME_APPLICATION_SRGS_XML = "application/srgs+xml";
public static final String MIME_APPLICATION_VND_MIF = "application/vnd.mif";
public static final String MIME_APPLICATION_VND_MSEXCEL = "application/vnd.ms-excel";
public static final String MIME_APPLICATION_VND_MSPOWERPOINT= "application/vnd.ms-powerpoint";
public static final String MIME_APPLICATION_VND_RNREALMEDIA = "application/vnd.rn-realmedia";
public static final String MIME_APPLICATION_X_BCPIO = "application/x-bcpio";
public static final String MIME_APPLICATION_X_CDLINK = "application/x-cdlink";
public static final String MIME_APPLICATION_X_CHESS_PGN = "application/x-chess-pgn";
public static final String MIME_APPLICATION_X_CPIO = "application/x-cpio";
public static final String MIME_APPLICATION_X_CSH = "application/x-csh";
public static final String MIME_APPLICATION_X_DIRECTOR = "application/x-director";
public static final String MIME_APPLICATION_X_DVI = "application/x-dvi";
public static final String MIME_APPLICATION_X_FUTURESPLASH = "application/x-futuresplash";
public static final String MIME_APPLICATION_X_GTAR = "application/x-gtar";
public static final String MIME_APPLICATION_X_HDF = "application/x-hdf";
public static final String MIME_APPLICATION_X_JAVASCRIPT = "application/x-javascript";
public static final String MIME_APPLICATION_X_KOAN = "application/x-koan";
public static final String MIME_APPLICATION_X_LATEX = "application/x-latex";
public static final String MIME_APPLICATION_X_NETCDF = "application/x-netcdf";
public static final String MIME_APPLICATION_X_OGG = "application/x-ogg";
public static final String MIME_APPLICATION_X_SH = "application/x-sh";
public static final String MIME_APPLICATION_X_SHAR = "application/x-shar";
public static final String MIME_APPLICATION_X_SHOCKWAVE_FLASH = "application/x-shockwave-flash";
public static final String MIME_APPLICATION_X_STUFFIT = "application/x-stuffit";
public static final String MIME_APPLICATION_X_SV4CPIO = "application/x-sv4cpio";
public static final String MIME_APPLICATION_X_SV4CRC = "application/x-sv4crc";
public static final String MIME_APPLICATION_X_TAR = "application/x-tar";
public static final String MIME_APPLICATION_X_RAR_COMPRESSED= "application/x-rar-compressed";
public static final String MIME_APPLICATION_X_TCL = "application/x-tcl";
public static final String MIME_APPLICATION_X_TEX = "application/x-tex";
public static final String MIME_APPLICATION_X_TEXINFO = "application/x-texinfo";
public static final String MIME_APPLICATION_X_TROFF = "application/x-troff";
public static final String MIME_APPLICATION_X_TROFF_MAN = "application/x-troff-man";
public static final String MIME_APPLICATION_X_TROFF_ME = "application/x-troff-me";
public static final String MIME_APPLICATION_X_TROFF_MS = "application/x-troff-ms";
public static final String MIME_APPLICATION_X_USTAR = "application/x-ustar";
public static final String MIME_APPLICATION_X_WAIS_SOURCE = "application/x-wais-source";
public static final String MIME_APPLICATION_VND_MOZZILLA_XUL_XML = "application/vnd.mozilla.xul+xml";
public static final String MIME_APPLICATION_XHTML_XML = "application/xhtml+xml";
public static final String MIME_APPLICATION_XSLT_XML = "application/xslt+xml";
public static final String MIME_APPLICATION_XML = "application/xml";
public static final String MIME_APPLICATION_XML_DTD = "application/xml-dtd";
public static final String MIME_IMAGE_BMP = "image/bmp";
public static final String MIME_IMAGE_CGM = "image/cgm";
public static final String MIME_IMAGE_GIF = "image/gif";
public static final String MIME_IMAGE_IEF = "image/ief";
public static final String MIME_IMAGE_JPEG = "image/jpeg";
public static final String MIME_IMAGE_TIFF = "image/tiff";
public static final String MIME_IMAGE_PNG = "image/png";
public static final String MIME_IMAGE_SVG_XML = "image/svg+xml";
public static final String MIME_IMAGE_VND_DJVU = "image/vnd.djvu";
public static final String MIME_IMAGE_WAP_WBMP = "image/vnd.wap.wbmp";
public static final String MIME_IMAGE_X_CMU_RASTER = "image/x-cmu-raster";
public static final String MIME_IMAGE_X_ICON = "image/x-icon";
public static final String MIME_IMAGE_X_PORTABLE_ANYMAP = "image/x-portable-anymap";
public static final String MIME_IMAGE_X_PORTABLE_BITMAP = "image/x-portable-bitmap";
public static final String MIME_IMAGE_X_PORTABLE_GRAYMAP = "image/x-portable-graymap";
public static final String MIME_IMAGE_X_PORTABLE_PIXMAP = "image/x-portable-pixmap";
public static final String MIME_IMAGE_X_RGB = "image/x-rgb";
public static final String MIME_AUDIO_BASIC = "audio/basic";
public static final String MIME_AUDIO_MIDI = "audio/midi";
public static final String MIME_AUDIO_MPEG = "audio/mpeg";
public static final String MIME_AUDIO_X_AIFF = "audio/x-aiff";
public static final String MIME_AUDIO_X_MPEGURL = "audio/x-mpegurl";
public static final String MIME_AUDIO_X_PN_REALAUDIO = "audio/x-pn-realaudio";
public static final String MIME_AUDIO_X_WAV = "audio/x-wav";
public static final String MIME_CHEMICAL_X_PDB = "chemical/x-pdb";
public static final String MIME_CHEMICAL_X_XYZ = "chemical/x-xyz";
public static final String MIME_MODEL_IGES = "model/iges";
public static final String MIME_MODEL_MESH = "model/mesh";
public static final String MIME_MODEL_VRLM = "model/vrml";
public static final String MIME_TEXT_PLAIN = "text/plain";
public static final String MIME_TEXT_RICHTEXT = "text/richtext";
public static final String MIME_TEXT_RTF = "text/rtf";
public static final String MIME_TEXT_HTML = "text/html";
public static final String MIME_TEXT_CALENDAR = "text/calendar";
public static final String MIME_TEXT_CSS = "text/css";
public static final String MIME_TEXT_SGML = "text/sgml";
public static final String MIME_TEXT_TAB_SEPARATED_VALUES = "text/tab-separated-values";
public static final String MIME_TEXT_VND_WAP_XML = "text/vnd.wap.wml";
public static final String MIME_TEXT_VND_WAP_WMLSCRIPT = "text/vnd.wap.wmlscript";
public static final String MIME_TEXT_X_SETEXT = "text/x-setext";
public static final String MIME_TEXT_X_COMPONENT = "text/x-component";
public static final String MIME_VIDEO_QUICKTIME = "video/quicktime";
public static final String MIME_VIDEO_MPEG = "video/mpeg";
public static final String MIME_VIDEO_VND_MPEGURL = "video/vnd.mpegurl";
public static final String MIME_VIDEO_X_MSVIDEO = "video/x-msvideo";
public static final String MIME_VIDEO_X_MS_WMV = "video/x-ms-wmv";
public static final String MIME_VIDEO_X_SGI_MOVIE = "video/x-sgi-movie";
public static final String MIME_X_CONFERENCE_X_COOLTALK = "x-conference/x-cooltalk";
private static HashMap<String, String> mimeTypeMapping;
static {
mimeTypeMapping = new HashMap<String, String>(200) {
private void put1(String key, String value) {
if (put(key, value) != null) {
throw new IllegalArgumentException("Duplicated extension: " + key);
}
}
{
put1("xul", MIME_APPLICATION_VND_MOZZILLA_XUL_XML);
put1("json", MIME_APPLICATION_JSON);
put1("ice", MIME_X_CONFERENCE_X_COOLTALK);
put1("movie", MIME_VIDEO_X_SGI_MOVIE);
put1("avi", MIME_VIDEO_X_MSVIDEO);
put1("wmv", MIME_VIDEO_X_MS_WMV);
put1("m4u", MIME_VIDEO_VND_MPEGURL);
put1("mxu", MIME_VIDEO_VND_MPEGURL);
put1("htc", MIME_TEXT_X_COMPONENT);
put1("etx", MIME_TEXT_X_SETEXT);
put1("wmls", MIME_TEXT_VND_WAP_WMLSCRIPT);
put1("wml", MIME_TEXT_VND_WAP_XML);
put1("tsv", MIME_TEXT_TAB_SEPARATED_VALUES);
put1("sgm", MIME_TEXT_SGML);
put1("sgml", MIME_TEXT_SGML);
put1("css", MIME_TEXT_CSS);
put1("ifb", MIME_TEXT_CALENDAR);
put1("ics", MIME_TEXT_CALENDAR);
put1("wrl", MIME_MODEL_VRLM);
put1("vrlm", MIME_MODEL_VRLM);
put1("silo", MIME_MODEL_MESH);
put1("mesh", MIME_MODEL_MESH);
put1("msh", MIME_MODEL_MESH);
put1("iges", MIME_MODEL_IGES);
put1("igs", MIME_MODEL_IGES);
put1("rgb", MIME_IMAGE_X_RGB);
put1("ppm", MIME_IMAGE_X_PORTABLE_PIXMAP);
put1("pgm", MIME_IMAGE_X_PORTABLE_GRAYMAP);
put1("pbm", MIME_IMAGE_X_PORTABLE_BITMAP);
put1("pnm", MIME_IMAGE_X_PORTABLE_ANYMAP);
put1("ico", MIME_IMAGE_X_ICON);
put1("ras", MIME_IMAGE_X_CMU_RASTER);
put1("wbmp", MIME_IMAGE_WAP_WBMP);
put1("djv", MIME_IMAGE_VND_DJVU);
put1("djvu", MIME_IMAGE_VND_DJVU);
put1("svg", MIME_IMAGE_SVG_XML);
put1("ief", MIME_IMAGE_IEF);
put1("cgm", MIME_IMAGE_CGM);
put1("bmp", MIME_IMAGE_BMP);
put1("xyz", MIME_CHEMICAL_X_XYZ);
put1("pdb", MIME_CHEMICAL_X_PDB);
put1("ra", MIME_AUDIO_X_PN_REALAUDIO);
put1("ram", MIME_AUDIO_X_PN_REALAUDIO);
put1("m3u", MIME_AUDIO_X_MPEGURL);
put1("aifc", MIME_AUDIO_X_AIFF);
put1("aif", MIME_AUDIO_X_AIFF);
put1("aiff", MIME_AUDIO_X_AIFF);
put1("mp3", MIME_AUDIO_MPEG);
put1("mp2", MIME_AUDIO_MPEG);
put1("mp1", MIME_AUDIO_MPEG);
put1("mpga", MIME_AUDIO_MPEG);
put1("kar", MIME_AUDIO_MIDI);
put1("mid", MIME_AUDIO_MIDI);
put1("midi", MIME_AUDIO_MIDI);
put1("dtd", MIME_APPLICATION_XML_DTD);
put1("xsl", MIME_APPLICATION_XML);
put1("xml", MIME_APPLICATION_XML);
put1("xslt", MIME_APPLICATION_XSLT_XML);
put1("xht", MIME_APPLICATION_XHTML_XML);
put1("xhtml", MIME_APPLICATION_XHTML_XML);
put1("src", MIME_APPLICATION_X_WAIS_SOURCE);
put1("ustar", MIME_APPLICATION_X_USTAR);
put1("ms", MIME_APPLICATION_X_TROFF_MS);
put1("me", MIME_APPLICATION_X_TROFF_ME);
put1("man", MIME_APPLICATION_X_TROFF_MAN);
put1("roff", MIME_APPLICATION_X_TROFF);
put1("tr", MIME_APPLICATION_X_TROFF);
put1("t", MIME_APPLICATION_X_TROFF);
put1("texi", MIME_APPLICATION_X_TEXINFO);
put1("texinfo", MIME_APPLICATION_X_TEXINFO);
put1("tex", MIME_APPLICATION_X_TEX);
put1("tcl", MIME_APPLICATION_X_TCL);
put1("sv4crc", MIME_APPLICATION_X_SV4CRC);
put1("sv4cpio", MIME_APPLICATION_X_SV4CPIO);
put1("sit", MIME_APPLICATION_X_STUFFIT);
put1("swf", MIME_APPLICATION_X_SHOCKWAVE_FLASH);
put1("shar", MIME_APPLICATION_X_SHAR);
put1("sh", MIME_APPLICATION_X_SH);
put1("cdf", MIME_APPLICATION_X_NETCDF);
put1("nc", MIME_APPLICATION_X_NETCDF);
put1("latex", MIME_APPLICATION_X_LATEX);
put1("skm", MIME_APPLICATION_X_KOAN);
put1("skt", MIME_APPLICATION_X_KOAN);
put1("skd", MIME_APPLICATION_X_KOAN);
put1("skp", MIME_APPLICATION_X_KOAN);
put1("js", MIME_APPLICATION_X_JAVASCRIPT);
put1("hdf", MIME_APPLICATION_X_HDF);
put1("gtar", MIME_APPLICATION_X_GTAR);
put1("spl", MIME_APPLICATION_X_FUTURESPLASH);
put1("dvi", MIME_APPLICATION_X_DVI);
put1("dxr", MIME_APPLICATION_X_DIRECTOR);
put1("dir", MIME_APPLICATION_X_DIRECTOR);
put1("dcr", MIME_APPLICATION_X_DIRECTOR);
put1("csh", MIME_APPLICATION_X_CSH);
put1("cpio", MIME_APPLICATION_X_CPIO);
put1("pgn", MIME_APPLICATION_X_CHESS_PGN);
put1("vcd", MIME_APPLICATION_X_CDLINK);
put1("bcpio", MIME_APPLICATION_X_BCPIO);
put1("rm", MIME_APPLICATION_VND_RNREALMEDIA);
put1("ppt", MIME_APPLICATION_VND_MSPOWERPOINT);
put1("mif", MIME_APPLICATION_VND_MIF);
put1("grxml", MIME_APPLICATION_SRGS_XML);
put1("gram", MIME_APPLICATION_SRGS);
put1("smil", MIME_APPLICATION_RDF_SMIL);
put1("smi", MIME_APPLICATION_RDF_SMIL);
put1("rdf", MIME_APPLICATION_RDF_XML);
put1("ogg", MIME_APPLICATION_X_OGG);
put1("oda", MIME_APPLICATION_ODA);
put1("dmg", MIME_APPLICATION_OCTET_STREAM);
put1("lzh", MIME_APPLICATION_OCTET_STREAM);
put1("so", MIME_APPLICATION_OCTET_STREAM);
put1("lha", MIME_APPLICATION_OCTET_STREAM);
put1("dms", MIME_APPLICATION_OCTET_STREAM);
put1("bin", MIME_APPLICATION_OCTET_STREAM);
put1("mathml", MIME_APPLICATION_MATHML_XML);
put1("cpt", MIME_APPLICATION_MAC_COMPACTPRO);
put1("hqx", MIME_APPLICATION_MAC_BINHEX40);
put1("jnlp", MIME_APPLICATION_JNLP);
put1("ez", MIME_APPLICATION_ANDREW_INSET);
put1("txt", MIME_TEXT_PLAIN);
put1("ini", MIME_TEXT_PLAIN);
put1("c", MIME_TEXT_PLAIN);
put1("h", MIME_TEXT_PLAIN);
put1("cpp", MIME_TEXT_PLAIN);
put1("cxx", MIME_TEXT_PLAIN);
put1("cc", MIME_TEXT_PLAIN);
put1("chh", MIME_TEXT_PLAIN);
put1("java", MIME_TEXT_PLAIN);
put1("csv", MIME_TEXT_PLAIN);
put1("bat", MIME_TEXT_PLAIN);
put1("cmd", MIME_TEXT_PLAIN);
put1("asc", MIME_TEXT_PLAIN);
put1("rtf", MIME_TEXT_RTF);
put1("rtx", MIME_TEXT_RICHTEXT);
put1("html", MIME_TEXT_HTML);
put1("htm", MIME_TEXT_HTML);
put1("zip", MIME_APPLICATION_ZIP);
put1("rar", MIME_APPLICATION_X_RAR_COMPRESSED);
put1("gzip", MIME_APPLICATION_X_GZIP);
put1("gz", MIME_APPLICATION_X_GZIP);
put1("tgz", MIME_APPLICATION_TGZ);
put1("tar", MIME_APPLICATION_X_TAR);
put1("gif", MIME_IMAGE_GIF);
put1("jpeg", MIME_IMAGE_JPEG);
put1("jpg", MIME_IMAGE_JPEG);
put1("jpe", MIME_IMAGE_JPEG);
put1("tiff", MIME_IMAGE_TIFF);
put1("tif", MIME_IMAGE_TIFF);
put1("png", MIME_IMAGE_PNG);
put1("au", MIME_AUDIO_BASIC);
put1("snd", MIME_AUDIO_BASIC);
put1("wav", MIME_AUDIO_X_WAV);
put1("mov", MIME_VIDEO_QUICKTIME);
put1("qt", MIME_VIDEO_QUICKTIME);
put1("mpeg", MIME_VIDEO_MPEG);
put1("mpg", MIME_VIDEO_MPEG);
put1("mpe", MIME_VIDEO_MPEG);
put1("abs", MIME_VIDEO_MPEG);
put1("doc", MIME_APPLICATION_MSWORD);
put1("xls", MIME_APPLICATION_VND_MSEXCEL);
put1("eps", MIME_APPLICATION_POSTSCRIPT);
put1("ai", MIME_APPLICATION_POSTSCRIPT);
put1("ps", MIME_APPLICATION_POSTSCRIPT);
put1("pdf", MIME_APPLICATION_PDF);
put1("exe", MIME_APPLICATION_OCTET_STREAM);
put1("dll", MIME_APPLICATION_OCTET_STREAM);
put1("class", MIME_APPLICATION_OCTET_STREAM);
put1("jar", MIME_APPLICATION_JAVA_ARCHIVE);
}};
}
public static void main(String[] args) {
System.out.println(mimeTypeMapping.size());
}
/**
* Registers MIME type for provided extension. Existing extension type will be overriden.
*/
public static void registerMimeType(String ext, String mimeType) {
mimeTypeMapping.put(ext, mimeType);
}
/**
* Returns the corresponding MIME type to the given extension.
* If no MIME type was found it returns 'application/octet-stream' type.
*/
public static String getMimeType(String ext) {
String mimeType = lookupMimeType(ext);
if (mimeType == null) {
mimeType = MIME_APPLICATION_OCTET_STREAM;
}
return mimeType;
}
/**
* Simply returns MIME type or <code>null</code> if no type is found.
*/
public static String lookupMimeType(String ext) {
return mimeTypeMapping.get(ext.toLowerCase());
}
}
That way you could obtain the extension from the content-type...
这样你就可以从内容类型中获取扩展名......
回答by Jo?o Wiciuk
To get the file extension You could do:
要获取文件扩展名，您可以执行以下操作：
multipartFile.getOriginalFilename().split("\.")[1];
The name You get with:
你得到的名字：
multipartFile.getOriginalFilename().split("\.")[0];
What if the user upload a executable file with .doc extension? You could get the content type:
如果用户上传带有 .doc 扩展名的可执行文件怎么办？您可以获得内容类型：
multipartFile.getContentType();
This will return a MIME type string. To get the correct file extension you could search the file name string for the last dot and then split it at this position.
这将返回一个 MIME 类型字符串。要获得正确的文件扩展名，您可以在文件名字符串中搜索最后一个点，然后在此位置拆分它。
回答by Veesta
You can use Tika https://tika.apache.org/
您可以使用 Tika https://tika.apache.org/
//file is a MultipartFile
if(!file.isEmpty)
{
Tika tika = new Tika();
String detectedType = tika.detect(file.getBytes());
System.out.println(detectedType);
}
This should get you the mimetype without saving the file
这应该可以让您在不保存文件的情况下获得 mimetype
回答by Amer Qarabsa
I solved the issue with splitting on . and taking the last part (not the 2nd),
我通过拆分解决了这个问题。并参加最后一部分（不是第二部分），
To get Extension
获取扩展
String[] fileFrags = file.getOriginalFilename().split("\.")
String extension = fileFrags[fileFrags.length-1]
To get the name
获取名称
String fileName = file.substring(0,file.lenghth()-fileFrags[fileFrags-1].length()-1)
回答by Mathias G.
For me, the cleanest solution:
对我来说，最干净的解决方案：
using FilenameUtils of org.apache.commons.io:
使用 org.apache.commons.io 的 FilenameUtils：
String extension = FilenameUtils.getExtension(file.getOriginalFilename());
回答by Mirna De Jesus
Given the String filename, you can do:
鉴于 String filename，您可以执行以下操作：
filename.substring(filename.lastIndexOf(".") + 1);
回答by Asanka Sampath
String extension = FilenameUtils.getExtension(inputFile.getOriginalFilename());
System.out.println("File Extension "+extension);
