Determine the file type based on the first few bytes of the file content

Determine with the file header. Directly read the first few bytes of the file. </P> <p> the file headers of common files are as follows: <br/> JPEG (JPG), file header: ffd8ff <br/> PNG (PNG), and file header: 89504e47 <br/> GIF (GIF), file header: 47494638 <br/> tiff (TIF), file header: 49347a00 <br/> Windows Bitmap (BMP), file header: development d <br/> CAD (DWG), file header: 41433130 <br/> Adobe Photoshop (PSD), file header: 38425053 <br/> Rich Text Format (RTF), file header: 7b5c727466 <br/> XML (XML), file header: 3c3f786d6c <br/> HTML (HTML), file header: 68746d6c3e <br/> email [thorough only] (EML), file header: outlook Express (DBX), file header: cfad12fec5fd746f <br/> Outlook (PST), file header: 2142444e <br/> MS Word/Excel (xls.or.doc), file header: d0cf11e0 <br/> MS Access (MDB), file header: 5374616e64617424204a <br/> Wordperfect (WPD), file header: ff575043 <br/> postscript (EPS. or. PS), file header: 252150532d41646f6265 <br/> Adobe Acrobat (PDF), file header: 255044462d312e <br/> quicken (qdf), file header: ac9ebd8f <br/> Windows Password (pwl), file header: e3828596 <br/> ZIP Archive (ZIP), file header: 504b0304 <br/> RAR Archive (RAR), file header: 52617221 <br/> wave (WAV), file header: 57415645 <br/> AVI (AVI), file header: 41564920 <br/> Real Audio (RAM), file header: 2e00001fd <br/> Real Media (RM), file header: 2e524d46 <br/> MPEG (MPG), file header: 000001ba <br/> MPEG (MPG), file header: 000001b3 <br/> QuickTime (mov), file header: 6d6f6f76 <br/> Windows Media (ASF), file header: 3026b2758e66cf11 <br/> Midi (MID), file header: 4d546864 </P> <p> package Org. test; </P> <p> Import Java. io. fileinputstream; </P> <p> public class test {</P> <p> Public static string bytestohexstring (byte [] SRC) {<br/> stringbuilder = new stringbuilder (); <br/> If (src = NULL | SRC. length <= 0) {<br/> return NULL; <br/>}< br/> for (INT I = 0; I <SRC. length; I ++) {<br/> int v = SRC [I] & 0xff; <br/> string HV = integer. tohexstring (V); <br/> If (HV. length () <2) {<br/> stringbuilder. append (0); <br/>}< br/> stringbuilder. append (HV); <br/>}< br/> return stringbuilder. tostring (); <br/>}</P> <p>/** <br/> * @ Param ARGs <br/> */<br/> Public static void main (string [] ARGs) throws exception {<br/> fileinputstream is = new fileinputstream ("D: // face.jpg"); <br/> byte [] B = new byte [3]; <br/> is. read (B, 0, B. length); <br/> system. out. println (bytestohexstring (B); </P> <p >}< br/>