java根據檔案流判斷檔案型別
阿新 • • 發佈:2019-02-19
原文https://www.cnblogs.com/chenglc/p/7117847.html
import java.io.FileInputStream; public class FileType{ public static String bytesToHexString(byte[] src) { StringBuilder stringBuilder = new StringBuilder(); if (src == null || 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(); }/** * @param args */ public static void main(String[] args) throws Exception { FileInputStream is = new FileInputStream("F:\\相簿\\微信圖片\\03.jpg"); byte[] b = new byte[3]; is.read(b, 0, b.length); String xxx = bytesToHexString(b); xxx = xxx.toUpperCase(); System.out.println("標頭檔案是:" + xxx); String ooo = TypeDict.checkType(xxx); System.out.println("字尾名是:" + ooo); } }
public class TypeDict { /** 常用檔案的檔案頭如下:(以前六位為準) JPEG (jpg),檔案頭:FFD8FF PNG (png),檔案頭:89504E47 GIF (gif),檔案頭:47494638 TIFF (tif),檔案頭:49492A00 Windows Bitmap (bmp),檔案頭:424D CAD (dwg),檔案頭:41433130 Adobe Photoshop (psd),檔案頭:38425053 Rich Text Format (rtf),檔案頭:7B5C727466 XML (xml),檔案頭:3C3F786D6C HTML (html),檔案頭:68746D6C3E Email [thorough only] (eml),檔案頭:44656C69766572792D646174653A Outlook Express (dbx),檔案頭:CFAD12FEC5FD746F Outlook (pst),檔案頭:2142444E MS Word/Excel (xls.or.doc),檔案頭:D0CF11E0 MS Access (mdb),檔案頭:5374616E64617264204A WordPerfect (wpd),檔案頭:FF575043 Postscript (eps.or.ps),檔案頭:252150532D41646F6265 Adobe Acrobat (pdf),檔案頭:255044462D312E Quicken (qdf),檔案頭:AC9EBD8F Windows Password (pwl),檔案頭:E3828596 ZIP Archive (zip),檔案頭:504B0304 RAR Archive (rar),檔案頭:52617221 Wave (wav),檔案頭:57415645 AVI (avi),檔案頭:41564920 Real Audio (ram),檔案頭:2E7261FD Real Media (rm),檔案頭:2E524D46 MPEG (mpg),檔案頭:000001BA MPEG (mpg),檔案頭:000001B3 Quicktime (mov),檔案頭:6D6F6F76 Windows Media (asf),檔案頭:3026B2758E66CF11 MIDI (mid),檔案頭:4D546864 */ public static String checkType(String xxxx) { switch (xxxx) { case "FFD8FF": return "jpg"; case "89504E": return "png"; case "474946": return "jif"; default: return "0000"; } } }