public void downloadAndVerifyAPK(Context context) { try { // Download APK file URL url = new URL(APK_URL); HttpURLConnection connection = (HttpURLConnection) url.openConnection(); connection.connect(); InputStream inputStream = connection.getInputStream();

// Verify APK file String calculatedMD5 = calculateMD5(apkFile); if (calculatedMD5.equals(APK_MD5)) { // APK file is verified, install it installAPK(context, apkFile); } else { // APK file is corrupted or tampered with Toast.makeText(context, "APK file verification failed", Toast.LENGTH_SHORT).show(); } } catch (Exception e) { // Handle exceptions } }

private String calculateMD5(File file) throws NoSuchAlgorithmException, IOException { MessageDigest md = MessageDigest.getInstance("MD5"); FileInputStream fis = new FileInputStream(file); byte[] buffer = new byte[1024]; int bytesRead; while ((bytesRead = fis.read(buffer)) != -1) { md.update(buffer, 0, bytesRead); } fis.close(); byte[] digest = md.digest(); return bytesToHex(digest); }