C # simple MD5 verification with Java

C # End

Using system; using system. io; using system. security. cryptography; the MD5 value of the namespace calculation file {class md5_helper {// <summary> // file MD5 verification /// </Summary> /// <Param name = "pathname"> absolute file path </param> /// <returns> MD5 Verification Code </returns> Public String getmd5hash (string pathname) {string strresult = ""; string strhashdata = ""; byte [] arrbythashvalue; filestream ofilestream = NULL; md5cipher serviceprovider omd5hasher = new md5cryptoserviceprovider (); try {ofilestream = new filestream (pathname, filemode. open, fileaccess. read, fileshare. readwrite); arrbythashvalue = omd5hasher. computehash (ofilestream); // calculate the hash value of the specified stream object ofilestream. close (); // a string consisting of a hex pair separated by a hyphen, where each pair represents the corresponding element in the value; for example, "F-2C-4A" strhashdata = bitconverter. tostring (arrbythashvalue); // replace-strhashdata = strhashdata. replace ("-", ""); strresult = strhashdata;} catch (system. exception ex) {} return strresult ;} /// <summary> /// check the byte array /// </Summary> /// <Param name = "buffer"> waiting for byte array </param> /// <returns> MD5 Verification Code </returns> Public String getmd5hash (byte [] buffer) {string strresult = ""; string strhashdata = ""; byte [] arrbythashvalue; md5cryptoserviceprovider omd5hasher = new md5cryptoserviceprovider (); try {arrbythashvalue = omd5hasher. computehash (buffer); // calculate the hash value of a specified stream object // a string consisting of a hexadecimal pair separated by a hyphen, where each pair represents the corresponding element of the value; for example, "F-2C-4A" strhashdata = bitconverter. tostring (arrbythashvalue); // replace-strhashdata = strhashdata. replace ("-", ""); strresult = strhashdata;} catch (system. exception ex) {} return strresult ;}}}

Java end

Package com; import Java. io. file; import Java. io. fileinputstream; import Java. io. ioexception; import Java. io. inputstream; import Java. security. messagedigest; import Java. security. nosuchalgorithmexception; public class md5util {/*** default password string combination, used to convert bytes into hexadecimal characters, apache verifies the correctness of downloaded files using the default combination */protected static char hexdigits [] = {'0', '1', '2', '3 ', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D ', 'E', 'F'}; protected static messagedigest = NULL; static {try {messagedigest = messagedigest. getinstance ("MD5");} catch (nosuchalgorithmexception e) {e. printstacktrace () ;}} public static void main (string [] ARGs) throws ioexception {byte [] buffer = "helloworld ". getbytes (); // byte array validation string md55 = getfilemd5string (buffer); system. out. println ("md55:" + md55);} public static string getfilemd5string (File file) throws ioexception {inputstream FS; FS = new fileinputstream (File ); byte [] buffer = new byte [1024]; int numread = 0; while (numread = Fi. read (buffer)> 0) {messagedigest. update (buffer, 0, numread);} FCM. close (); Return buffertohex (messagedigest. digest ();} public static string getfilemd5string (byte [] buffer) throws ioexception {messagedigest. update (buffer, 0, buffer. length); Return buffertohex (messagedigest. digest ();} Private Static string buffertohex (byte bytes []) {return buffertohex (bytes, 0, bytes. length);} Private Static string buffertohex (byte bytes [], int M, int N) {stringbuffer = new stringbuffer (2 * n); int K = m + N; for (int l = m; L <K; l ++) {appendhexpair (Bytes [L], stringbuffer);} return stringbuffer. tostring ();} Private Static void appendhexpair (byte BT, stringbuffer) {char C0 = hexdigits [(BT & 0xf0)> 4]; // convert the numbers with four or more characters in a byte to the right of the logic. Shift the symbols right together. No difference is found between the two symbols: Char C1 = hexdigits [BT & 0xf]; // convert the numbers in the middle or lower byte to stringbuffer. append (C0); stringbuffer. append (C1 );}}