转自：https://blog.csdn.net/useprogram/article/details/90637401

public class FileTypeUtil {

private final static Map FILE_TYPE_MAP = new HashMap();

private static Logger log = LoggerFactory.getLogger(FileTypeUtil.class);

private FileTypeUtil(){}

static{

getAllFileType(); //初始化文件类型信息

}

private static void getAllFileType(){

FILE_TYPE_MAP.put("ffd8ffe000104a464946", "jpg"); //JPEG (jpg)

FILE_TYPE_MAP.put("89504e470d0a1a0a0000", "png"); //PNG (png)

FILE_TYPE_MAP.put("47494638396126026f01", "gif"); //GIF (gif)

FILE_TYPE_MAP.put("49492a00227105008037", "tif"); //TIFF (tif)

FILE_TYPE_MAP.put("424d228c010000000000", "bmp"); //16色位图(bmp)

FILE_TYPE_MAP.put("424d8240090000000000", "bmp"); //24位位图(bmp)

FILE_TYPE_MAP.put("424d8e1b030000000000", "bmp"); //256色位图(bmp)

FILE_TYPE_MAP.put("41433130313500000000", "dwg"); //CAD (dwg)

FILE_TYPE_MAP.put("3c21444f435459504520", "html"); //HTML (html)

FILE_TYPE_MAP.put("3c21646f637479706520", "htm"); //HTM (htm)

FILE_TYPE_MAP.put("48544d4c207b0d0a0942", "css"); //css

FILE_TYPE_MAP.put("696b2e71623d696b2e71", "js"); //js

FILE_TYPE_MAP.put("7b5c727466315c616e73", "rtf"); //Rich Text Format (rtf)

FILE_TYPE_MAP.put("38425053000100000000", "psd"); //Photoshop (psd)

FILE_TYPE_MAP.put("46726f6d3a203d3f6762", "eml"); //Email [Outlook Express 6] (eml)

FILE_TYPE_MAP.put("d0cf11e0a1b11ae10000", "doc"); //MS Excel 注意：word、msi 和 excel的文件头一样

FILE_TYPE_MAP.put("d0cf11e0a1b11ae10000", "vsd"); //Visio 绘图

FILE_TYPE_MAP.put("5374616E64617264204A", "mdb"); //MS Access (mdb)

FILE_TYPE_MAP.put("252150532D41646F6265", "ps");

FILE_TYPE_MAP.put("255044462d312e360d25", "pdf"); //Adobe Acrobat (pdf)

FILE_TYPE_MAP.put("2e524d46000000120001", "rmvb"); //rmvb/rm相同

FILE_TYPE_MAP.put("464c5601050000000900", "flv"); //flv与f4v相同

FILE_TYPE_MAP.put("00000020667479706973", "mp4");

FILE_TYPE_MAP.put("49443303000000000f76", "mp3");

FILE_TYPE_MAP.put("000001ba210001000180", "mpg"); //

FILE_TYPE_MAP.put("3026b2758e66cf11a6d9", "wmv"); //wmv与asf相同

FILE_TYPE_MAP.put("524946464694c9015741", "wav"); //Wave (wav)

FILE_TYPE_MAP.put("52494646d07d60074156", "avi");

FILE_TYPE_MAP.put("4d546864000000060001", "mid"); //MIDI (mid)

FILE_TYPE_MAP.put("504b0304140000000800", "zip");

FILE_TYPE_MAP.put("526172211a0700cf9073", "rar");

FILE_TYPE_MAP.put("235468697320636f6e66", "ini");

FILE_TYPE_MAP.put("504b03040a0000000000", "jar");

FILE_TYPE_MAP.put("4d5a9000030000000400", "exe");//可执行文件

FILE_TYPE_MAP.put("3c25402070616765206c", "jsp");//jsp文件

FILE_TYPE_MAP.put("4d616e69666573742d56", "mf");//MF文件

FILE_TYPE_MAP.put("3c3f786d6c2076657273", "xml");//xml文件

FILE_TYPE_MAP.put("efbbbf2f2a0d0a53514c", "sql");//xml文件

FILE_TYPE_MAP.put("7061636b616765207765", "java");//java文件

FILE_TYPE_MAP.put("406563686f206f66660d", "bat");//bat文件

FILE_TYPE_MAP.put("1f8b0800000000000000", "gz");//gz文件

FILE_TYPE_MAP.put("6c6f67346a2e726f6f74", "properties");//bat文件

FILE_TYPE_MAP.put("cafebabe0000002e0041", "class");//bat文件

FILE_TYPE_MAP.put("49545346030000006000", "chm");//bat文件

FILE_TYPE_MAP.put("04000000010000001300", "mxp");//bat文件

FILE_TYPE_MAP.put("504b0304140006000800", "docx");//docx文件

FILE_TYPE_MAP.put("d0cf11e0a1b11ae10000", "wps");//WPS文字wps、表格et、演示dps都是一样的

FILE_TYPE_MAP.put("6431303a637265617465", "torrent");

FILE_TYPE_MAP.put("494d4b48010100000200", "264");

FILE_TYPE_MAP.put("6D6F6F76", "mov"); //Quicktime (mov)

FILE_TYPE_MAP.put("FF575043", "wpd"); //WordPerfect (wpd)

FILE_TYPE_MAP.put("CFAD12FEC5FD746F", "dbx"); //Outlook Express (dbx)

FILE_TYPE_MAP.put("2142444E", "pst"); //Outlook (pst)

FILE_TYPE_MAP.put("AC9EBD8F", "qdf"); //Quicken (qdf)

FILE_TYPE_MAP.put("E3828596", "pwl"); //Windows Password (pwl)

FILE_TYPE_MAP.put("2E7261FD", "ram"); //Real Audio (ram)

FILE_TYPE_MAP.put("D0CF11E0","xls");

FILE_TYPE_MAP.put("504B0304","xlsx");

FILE_TYPE_MAP.put("5265644c","pptx");//ppt、pptx

}

/**

* 得到上传文件的文件头

* @param src

* @return

*/

private static String bytesToHexString(byte[] src){

StringBuilder stringBuilder = new StringBuilder();

if(null==src || src.length <= 0){

return null;

}

for(int i = 0; i < src.length; i++){

int v = src[i] & 0xFF;

String hv = Integer.toHexString(v);

if(hv.length() < 2){

stringBuilder.append(0);

}

stringBuilder.append(hv);

}

return stringBuilder.toString();

}

/**

* 获取文件类型

* @param file

* @return

*/

public static String getFileType(File file){

String res = null;

FileInputStream fis = null;

try{

fis = new FileInputStream(file);

//获取文件头的前六位

byte[] b = new byte[3];

fis.read(b, 0, b.length);

String fileCode = bytesToHexString(b);

Iterator keyIter = FILE_TYPE_MAP.keySet().iterator();

while(keyIter.hasNext()){

String key = keyIter.next();

//比较前几位是否相同就可以判断文件格式(相同格式文件文件头后面几位会有所变化)

if(key.toLowerCase().startsWith(fileCode.toLowerCase()) || fileCode.toLowerCase().startsWith(key.toLowerCase())){

res = FILE_TYPE_MAP.get(key);

break;

}

}

log.info("文件头:"+fileCode+"-----文件类型:"+res);

fis.close();

}catch(FileNotFoundException e){

e.printStackTrace();

}catch (IOException e){

e.printStackTrace();

}finally {

try {

fis.close();

}catch (IOException e) {

e.printStackTrace();

}

}

return res;

}

}