代码如下：
1 package com.util; 2 /** 3 * MD5编码工具类 4 * http://www.cnblogs.com/sosoft/ 5 */ 6 public class MD5Code { 7 static final int S11 = 7; 8 9 static final int S12 = 12; 10 11 static final int S13 = 17; 12 13 static final int S14 = 22; 14 15 static final int S21 = 5; 16 17 static final int S22 = 9; 18 19 static final int S23 = 14; 20 21 static final int S24 = 20; 22 23 static final int S31 = 4; 24 25 static final int S32 = 11; 26 27 static final int S33 = 16; 28 29 static final int S34 = 23; 30 31 static final int S41 = 6; 32 33 static final int S42 = 10; 34 35 static final int S43 = 15; 36 37 static final int S44 = 21; 38 39 static final byte[] PADDING = { -128, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 40 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 41 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 42 0, 0, 0, 0, 0, 0, 0 }; 43 44 private long[] state = new long[4];// state (ABCD) 45 46 private long[] count = new long[2];// number of bits, modulo 2^64 (lsb 47 48 // first) 49 50 private byte[] buffer = new byte[64]; // input buffer 51 52 53 public String digestHexStr; 54 55 private byte[] digest = new byte[16]; 56 57 public String getMD5ofStr(String inbuf) { 58 md5Init(); 59 md5Update(inbuf.getBytes(), inbuf.length()); 60 md5Final(); 61 digestHexStr = ""; 62 for (int i = 0; i < 16; i++) { 63 digestHexStr += byteHEX(digest[i]); 64 } 65 return digestHexStr; 66 } 67 68 public MD5Code() { 69 md5Init(); 70 return; 71 } 72 73 private void md5Init() { 74 count[0] = 0L; 75 count[1] = 0L; 76 // /* Load magic initialization constants. 77 state[0] = 0x67452301L; 78 state[1] = 0xefcdab89L; 79 state[2] = 0x98badcfeL; 80 state[3] = 0x10325476L; 81 return; 82 } 83 84 private long F(long x, long y, long z) { 85 return (x & y) | ((~x) & z); 86 } 87 88 private long G(long x, long y, long z) { 89 return (x & z) | (y & (~z)); 90 } 91 92 private long H(long x, long y, long z) { 93 return x ^ y ^ z; 94 } 95 96 private long I(long x, long y, long z) { 97 return y ^ (x | (~z)); 98 } 99 100 private long FF(long a, long b, long c, long d, long x, long s, long ac) {101 a += F(b, c, d) + x + ac;102 a = ((int) a << s) | ((int) a >>> (32 - s));103 a += b;104 return a;105 }106 107 private long GG(long a, long b, long c, long d, long x, long s, long ac) {108 a += G(b, c, d) + x + ac;109 a = ((int) a << s) | ((int) a >>> (32 - s));110 a += b;111 return a;112 }113 114 private long HH(long a, long b, long c, long d, long x, long s, long ac) {115 a += H(b, c, d) + x + ac;116 a = ((int) a << s) | ((int) a >>> (32 - s));117 a += b;118 return a;119 }120 121 private long II(long a, long b, long c, long d, long x, long s, long ac) {122 a += I(b, c, d) + x + ac;123 a = ((int) a << s) | ((int) a >>> (32 - s));124 a += b;125 return a;126 }127 128 private void md5Update(byte[] inbuf, int inputLen) {129 int i, index, partLen;130 byte[] block = new byte[64];131 index = (int) (count[0] >>> 3) & 0x3F;132 // /* Update number of bits */133 if ((count[0] += (inputLen << 3)) < (inputLen << 3))134 count[1]++;135 count[1] += (inputLen >>> 29);136 partLen = 64 - index;137 // Transform as many times as possible.138 if (inputLen >= partLen) {139 md5Memcpy(buffer, inbuf, index, 0, partLen);140 md5Transform(buffer);141 for (i = partLen; i + 63 < inputLen; i += 64) {142 md5Memcpy(block, inbuf, 0, i, 64);143 md5Transform(block);144 }145 index = 0;146 } else147 i = 0;148 // /* Buffer remaining input */149 md5Memcpy(buffer, inbuf, index, i, inputLen - i);150 }151 152 private void md5Final() {153 byte[] bits = new byte[8];154 int index, padLen;155 // /* Save number of bits */156 Encode(bits, count, 8);157 // /* Pad out to 56 mod 64.158 index = (int) (count[0] >>> 3) & 0x3f;159 padLen = (index < 56) ? (56 - index) : (120 - index);160 md5Update(PADDING, padLen);161 // /* Append length (before padding) */162 md5Update(bits, 8);163 // /* Store state in digest */164 Encode(digest, state, 16);165 }166 167 private void md5Memcpy(byte[] output, byte[] input, int outpos, int inpos,168 int len) {169 int i;170 for (i = 0; i < len; i++)171 output[outpos + i] = input[inpos + i];172 }173 174 private void md5Transform(byte block[]) {175 long a = state[0], b = state[1], c = state[2], d = state[3];176 long[] x = new long[16];177 Decode(x, block, 64);178 /* Round 1 */179 a = FF(a, b, c, d, x[0], S11, 0xd76aa478L); /* 1 */180 d = FF(d, a, b, c, x[1], S12, 0xe8c7b756L); /* 2 */181 c = FF(c, d, a, b, x[2], S13, 0x242070dbL); /* 3 */182 b = FF(b, c, d, a, x[3], S14, 0xc1bdceeeL); /* 4 */183 a = FF(a, b, c, d, x[4], S11, 0xf57c0fafL); /* 5 */184 d = FF(d, a, b, c, x[5], S12, 0x4787c62aL); /* 6 */185 c = FF(c, d, a, b, x[6], S13, 0xa8304613L); /* 7 */186 b = FF(b, c, d, a, x[7], S14, 0xfd469501L); /* 8 */187 a = FF(a, b, c, d, x[8], S11, 0x698098d8L); /* 9 */188 d = FF(d, a, b, c, x[9], S12, 0x8b44f7afL); /* 10 */189 c = FF(c, d, a, b, x[10], S13, 0xffff5bb1L); /* 11 */190 b = FF(b, c, d, a, x[11], S14, 0x895cd7beL); /* 12 */191 a = FF(a, b, c, d, x[12], S11, 0x6b901122L); /* 13 */192 d = FF(d, a, b, c, x[13], S12, 0xfd987193L); /* 14 */193 c = FF(c, d, a, b, x[14], S13, 0xa679438eL); /* 15 */194 b = FF(b, c, d, a, x[15], S14, 0x49b40821L); /* 16 */195 /* Round 2 */196 a = GG(a, b, c, d, x[1], S21, 0xf61e2562L); /* 17 */197 d = GG(d, a, b, c, x[6], S22, 0xc040b340L); /* 18 */198 c = GG(c, d, a, b, x[11], S23, 0x265e5a51L); /* 19 */199 b = GG(b, c, d, a, x[0], S24, 0xe9b6c7aaL); /* 20 */200 a = GG(a, b, c, d, x[5], S21, 0xd62f105dL); /* 21 */201 d = GG(d, a, b, c, x[10], S22, 0x2441453L); /* 22 */202 c = GG(c, d, a, b, x[15], S23, 0xd8a1e681L); /* 23 */203 b = GG(b, c, d, a, x[4], S24, 0xe7d3fbc8L); /* 24 */204 a = GG(a, b, c, d, x[9], S21, 0x21e1cde6L); /* 25 */205 d = GG(d, a, b, c, x[14], S22, 0xc33707d6L); /* 26 */206 c = GG(c, d, a, b, x[3], S23, 0xf4d50d87L); /* 27 */207 b = GG(b, c, d, a, x[8], S24, 0x455a14edL); /* 28 */208 a = GG(a, b, c, d, x[13], S21, 0xa9e3e905L); /* 29 */209 d = GG(d, a, b, c, x[2], S22, 0xfcefa3f8L); /* 30 */210 c = GG(c, d, a, b, x[7], S23, 0x676f02d9L); /* 31 */211 b = GG(b, c, d, a, x[12], S24, 0x8d2a4c8aL); /* 32 */212 /* Round 3 */213 a = HH(a, b, c, d, x[5], S31, 0xfffa3942L); /* 33 */214 d = HH(d, a, b, c, x[8], S32, 0x8771f681L); /* 34 */215 c = HH(c, d, a, b, x[11], S33, 0x6d9d6122L); /* 35 */216 b = HH(b, c, d, a, x[14], S34, 0xfde5380cL); /* 36 */217 a = HH(a, b, c, d, x[1], S31, 0xa4beea44L); /* 37 */218 d = HH(d, a, b, c, x[4], S32, 0x4bdecfa9L); /* 38 */219 c = HH(c, d, a, b, x[7], S33, 0xf6bb4b60L); /* 39 */220 b = HH(b, c, d, a, x[10], S34, 0xbebfbc70L); /* 40 */221 a = HH(a, b, c, d, x[13], S31, 0x289b7ec6L); /* 41 */222 d = HH(d, a, b, c, x[0], S32, 0xeaa127faL); /* 42 */223 c = HH(c, d, a, b, x[3], S33, 0xd4ef3085L); /* 43 */224 b = HH(b, c, d, a, x[6], S34, 0x4881d05L); /* 44 */225 a = HH(a, b, c, d, x[9], S31, 0xd9d4d039L); /* 45 */226 d = HH(d, a, b, c, x[12], S32, 0xe6db99e5L); /* 46 */227 c = HH(c, d, a, b, x[15], S33, 0x1fa27cf8L); /* 47 */228 b = HH(b, c, d, a, x[2], S34, 0xc4ac5665L); /* 48 */229 /* Round 4 */230 a = II(a, b, c, d, x[0], S41, 0xf4292244L); /* 49 */231 d = II(d, a, b, c, x[7], S42, 0x432aff97L); /* 50 */232 c = II(c, d, a, b, x[14], S43, 0xab9423a7L); /* 51 */233 b = II(b, c, d, a, x[5], S44, 0xfc93a039L); /* 52 */234 a = II(a, b, c, d, x[12], S41, 0x655b59c3L); /* 53 */235 d = II(d, a, b, c, x[3], S42, 0x8f0ccc92L); /* 54 */236 c = II(c, d, a, b, x[10], S43, 0xffeff47dL); /* 55 */237 b = II(b, c, d, a, x[1], S44, 0x85845dd1L); /* 56 */238 a = II(a, b, c, d, x[8], S41, 0x6fa87e4fL); /* 57 */239 d = II(d, a, b, c, x[15], S42, 0xfe2ce6e0L); /* 58 */240 c = II(c, d, a, b, x[6], S43, 0xa3014314L); /* 59 */241 b = II(b, c, d, a, x[13], S44, 0x4e0811a1L); /* 60 */242 a = II(a, b, c, d, x[4], S41, 0xf7537e82L); /* 61 */243 d = II(d, a, b, c, x[11], S42, 0xbd3af235L); /* 62 */244 c = II(c, d, a, b, x[2], S43, 0x2ad7d2bbL); /* 63 */245 b = II(b, c, d, a, x[9], S44, 0xeb86d391L); /* 64 */246 state[0] += a;247 state[1] += b;248 state[2] += c;249 state[3] += d;250 }251 252 private void Encode(byte[] output, long[] input, int len) {253 int i, j;254 for (i = 0, j = 0; j < len; i++, j += 4) {255 output[j] = (byte) (input[i] & 0xffL);256 output[j + 1] = (byte) ((input[i] >>> 8) & 0xffL);257 output[j + 2] = (byte) ((input[i] >>> 16) & 0xffL);258 output[j + 3] = (byte) ((input[i] >>> 24) & 0xffL);259 }260 }261 262 private void Decode(long[] output, byte[] input, int len) {263 int i, j;264 for (i = 0, j = 0; j < len; i++, j += 4)265 output[i] = b2iu(input[j]) | (b2iu(input[j + 1]) << 8)266 | (b2iu(input[j + 2]) << 16) | (b2iu(input[j + 3]) << 24);267 return;268 }269 270 public static long b2iu(byte b) {271 return b < 0 ? b & 0x7F + 128 : b;272 }273 274 public static String byteHEX(byte ib) {275 char[] Digit = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A',276 'B', 'C', 'D', 'E', 'F' };277 char[] ob = new char[2];278 ob[0] = Digit[(ib >>> 4) & 0X0F];279 ob[1] = Digit[ib & 0X0F];280 String s = new String(ob);281 return s;282 }283 }