judging whether the file is a GIF file
private boolean isGifFile(File file) { try { FileInputStream inputStream = new FileInputStream(file); int[] flags = new int[5]; flags[0] = inputStream.read(); flags[1] = inputStream.read(); flags[2] = inputStream.read(); flags[3] = inputStream.read(); inputStream.skip(inputStream.available() - 1); flags[4] = inputStream.read(); inputStream.close(); return flags[0] == 71 && flags[1] == 73 && flags[2] == 70 && flags[3] == 56 && flags[4] == 0x3B; } catch (FileNotFoundException e) { e.printStackTrace (); } catch (IOException e) { e.printStackTrace (); } catch (Exception e) { e.printStackTrace (); } return false; }
Determine if the file is a JPG file
private boolean isJpgFile(File file){ try { FileInputStream bin = new FileInputStream(file); int b[] = new int[4]; b[0] = bin.read(); b[1] = bin.read(); bin.skip(bin.available() - 2); b[2] = bin.read(); b[3] = bin.read(); bin.close(); return b[0] == 255 && b[1] == 216 && b[2] == 255 && b[3] == 217; } catch (FileNotFoundException e) { e.printStackTrace (); } catch (IOException e) { e.printStackTrace (); } catch (Exception e) { e.printStackTrace (); } return false; }