Java RC4 Encryption and decryption

Package com.*;p Ublic class RC4 {public static string DECRY_RC4 (byte[] data, string key) {if (data = = NULL | | key = NULL) {return null;} Return asstring (rc4base (data, key));} public static string DECRY_RC4 (string data, string key) {if (data = = NULL | | key = = NULL) {return null;} return new String (Rc4base (hexstring2bytes (data), key));} public static byte[] Encry_rc4_byte (string data, string key) {if (data = = NULL | | key = = NULL) {return null;} byte b_data[] = Data.getbytes (); return Rc4base (B_data, key);} public static string encry_rc4_string (string data, string key) {if (data = = NULL | | key = = NULL) {return null;} Return tohexstring (asstring (encry_rc4_byte (data, key));} private static String asstring (byte[] buf) {StringBuffer strbuf = new StringBuffer (buf.length); for (int i = 0; i < BUF. Length i++) {strbuf.append ((char) buf[i]);} return strbuf.tostring ();} private static byte[] Initkey (String akey) {byte[] B_key = Akey.getbytes (); byte state[] = new Byte[256];for (int i = 0; i < 256; i++){State[i] = (byte) i;} int index1 = 0;int Index2 = 0;if (B_key = = NULL | | b_key.length = 0) {return null;} for (int i = 0; i < i++) {Index2 = ((B_key[index1] & 0xff) + (State[i] & 0xff) + index2) & 0xff;byte t MP = State[i];state[i] = State[index2];state[index2] = Tmp;index1 = (index1 + 1)% B_key.length;} return state;} private static String tohexstring (string s) {string str = ""; for (int i = 0; I < s.length (); i++) {int ch = (int) s.charat (i); String s4 = integer.tohexstring (Ch & 0xFF); if (s4.length () = = 1) {s4 = ' 0 ' + S4;} str = str + s4;} Return str;//0x means hexadecimal}private static byte[] hexstring2bytes (String src) {int size = Src.length (); byte[] ret = new Byte[si ze/2];byte[] tmp = Src.getbytes (); for (int i = 0; i < SIZE/2; i++) {Ret[i] = unitebytes (Tmp[i * 2], Tmp[i * 2 + 1]) ;} return ret;} private static byte Unitebytes (byte src0, byte src1) {char _b0 = (char) byte.decode ("0x" + new String (new byte[] {SRC0}) ). Bytevalue (); _b0 = (char) (_b0 << 4); Char _b1 = (char) byte.decode ("0x" + new String (new byte[] {SRC1})). Bytevalue (); byte ret = (byte) (_b0 ^ _b1); return ret;} private static byte[] Rc4base (byte[] input, String mkkey) {int x = 0;int y = 0;byte key[] = Initkey (mkkey); int Xorindex;by Te[] result = new Byte[input.length];for (int i = 0; i < input.length; i++) {x = (x + 1) & 0xff;y = ((Key[x] & 0xff) + y) & 0xff;byte tmp = key[x];key[x] = Key[y];key[y] = Tmp;xorindex = ((Key[x] & 0xff) + (Key[y] & 0xff) ) & 0xff;result[i] = (byte) (Input[i] ^ key[xorindex]);} return result;} public static void Main (string[] args) {String inputstr = "Be a good man"; String str = encry_rc4_string (inputstr, "123456"); System.out.println (str); SYSTEM.OUT.PRINTLN (DECRY_RC4 (str, "123456"));}}

Java RC4 Encryption and decryption