JavaMD5实现将字符串散列为不正确的值

我查看了多个网站，以了解MD5算法是什么。然后我用我学到的东西用Java编写了一个方法，可以计算给定输入的MD5散列。我试图更改我认为不正确的代码的某些部分，但仍然无法为我尝试的某些字符串获取正确的哈希值。这是我的密码：

    import java.security.MessageDigest;
    import java.security.NoSuchAlgorithmException;

    class MD5 {
    public static void main(String[] args) throws NoSuchAlgorithmException {
        String[] msgs = new String[] { "", "md5", "MD5", "Java",
                "MessageDigest5", "1234", "123abc", "0123456789abcdef" };
        String[] strings = new String[msgs.length + args.length];
        System.arraycopy(msgs, 0, strings, 0, msgs.length);
        for (int i = msgs.length; i < strings.length; ++i)
            strings[i] = args[i - msgs.length];
        for (String s : strings) {
            System.out.print("MD5(\"" + s + "\") = ");
            byte[] md5 = md5(s.getBytes());
            byte[] java = MessageDigest.getInstance("MD5").digest(s.getBytes());
            StringBuilder sbmd5 = new StringBuilder();
            StringBuilder sbjava = new StringBuilder();
            for (int i = 0; i < 16; ++i) {
                sbmd5.append(String.format("%02x", md5[i] & 0xff));
                sbjava.append(String.format("%02x", java[i] & 0xff));
            }
            System.out.print("Java(" + sbjava.toString() + ") MD5(");
            System.out.print(sbmd5.toString() + ")");
            System.out.println();
        }
    }

    public static byte[] md5(byte[] data) {
        if (data == null)
            throw new NullPointerException();
        byte[] padding = new byte[] { (byte) 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
        int[] SHIFT = new int[] { 7, 12, 17, 22, 5, 9, 14, 20, 4, 11, 16, 23,
                6, 10, 15, 21 };
        int[] TABLE = new int[64];
        for (int i = 0; i < 64; ++i)
            TABLE[i] = (int) (long) ((1L << 32) * Math.abs(Math.sin(i + 1)));
        int A = 0x67452301; // 01234567
        int B = 0xefcdab89; // 89abcdef
        int C = 0x98badcfe; // fedcba98
        int D = 0x10325476; // 76543210
        // int A = 0x01234567;
        // int B = 0x89abcdef;
        // int C = 0xfedcba98;
        // int D = 0x76543210;
        byte[] msg = new byte[data.length + 64 - (data.length % 64)];
        System.arraycopy(data, 0, msg, 0, data.length);
        int padPos = 0;
        for (int i = data.length; i < msg.length; ++i)
            msg[i] = padding[padPos++];
        for (int i = 0; i < msg.length >>> 6; ++i) {
            int[] words = new int[16];
            int msgStart = i << 6;
            for (int j = 0; j < 16; ++j) {
                int k = j << 2;
                int begin = msgStart + k;
                words[j] = msg[begin] + (msg[begin + 1] << 8)
                        + (msg[begin + 2] << 16) + (msg[begin + 3] << 24);
            }
            int a0 = A;
            int b0 = B;
            int c0 = C;
            int d0 = D;
            for (int j = 0; j < 64; ++j) {
                int j16 = j >>> 4;
                int F;
                int index;
                switch (j16) {
                case 0:
                    F = (b0 & c0) | (~b0 & d0);
                    // F = d0 ^ (b0 & (c0 ^ d0));
                    index = j;
                    break;
                case 1:
                    F = (b0 & d0) | (c0 & ~d0);
                    // F = c0 ^ (d0 & (b0 ^ c0));
                    index = ((j * 5) + 1) & 15;
                    break;
                case 2:
                    F = b0 ^ c0 ^ d0;
                    index = ((j * 3) + 5) & 15;
                    break;
                default:
                    F = c0 ^ (b0 | ~d0);
                    index = (j * 7) & 15;
                    break;
                }
                int rotateValue = A + F + words[index] + TABLE[j];
                int rotateDistance = SHIFT[(j16 << 2) | (j & 3)];
                int temp = B
                        + ((rotateValue << rotateDistance) | (rotateValue >>> (32 - rotateDistance)));
                A = D;
                D = C;
                C = B;
                B = temp;
            }
            A += a0;
            B += b0;
            C += c0;
            D += d0;
        }
        byte[] result = new byte[16];
        int index = 0;
        for (int i = 0; i < 4; ++i) {
            int n = i == 0 ? A : (i == 1 ? B : (i == 2 ? C : D));
            for (int j = 0; j < 4; ++j) {
                result[index++] = (byte) n;
                n >>>= 8;
            }
        }
        return result;
    }
}

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你为什么要重新发明轮子？：）这个问题似乎离题了，因为它太本地化了。@EJP如果这仍然是离题的原因的话。但它可能是离题的，因为它属于codereview.stackexchange.com…@owlstead，这就是我给出的原因，如果这不再是一个有效的原因，那么这个网站将很快崩溃。当将字符串转换为字节时，您当然应该指定特定的编码。在您的情况下，ASCII或UTF-8将是最合适的。这并不能回答问题，您试图通过向试图学习哈希的用户提供一个标准库函数来强制用户使用另一种方法，该函数根本不会帮助他学习任何内容，您的代码没有格式化，这会使其更难阅读，你的代码是不完整的，最重要的是，你没有任何解释。如果可以的话，我会投两张反对票。

MD5("") = Java(d41d8cd98f00b204e9800998ecf8427e) MD5(6195f07125a3dab6a14e8e929a0ac5bf)
MD5("md5") = Java(1bc29b36f623ba82aaf6724fd3b16718) MD5(f382be5a669dd9ce3095a4aa2e55ff18)
MD5("MD5") = Java(7f138a09169b250e9dcb378140907378) MD5(af2ade546a995a239c94f5776393bfdd)
MD5("Java") = Java(d52387880e1ea22817a72d3759213819) MD5(f512715d4bc0728fd50994d6583d6370)
MD5("MessageDigest5") = Java(c39f3b584476f0fd9303fe2cba34a1de) MD5(85e2d27519fbf97c3f988e9ccb9564a6)
MD5("1234") = Java(81dc9bdb52d04dc20036dbd8313ed055) MD5(51e22a66d259c84c920d11f3b1048263)
MD5("123abc") = Java(a906449d5769fa7361d7ecc6aa3f6d28) MD5(e1254819f3127907cb3e95b3fa3b2e68)
MD5("0123456789abcdef") = Java(4032af8d61035123906e58e067140cc5) MD5(28fcda2be1f449185c73222e3a6e5ca4)

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.logging.Level;
import java.util.logging.Logger;

public void encrypt(){
    String password = new String(jPasswordField1.getPassword());

    MessageDigest algorithm = null;
    try {
        algorithm = MessageDigest.getInstance("MD5");
    } catch (NoSuchAlgorithmException ex) {
        Logger.getLogger(pe.class.getName()).log(Level.SEVERE, null, ex);
    }
    algorithm.reset();
    algorithm.update(password.getBytes());
    byte bytes [] = algorithm.digest();
    StringBuffer sb = new StringBuffer();
    for (byte b : bytes){
         String hex = Integer.toHexString(0xff & b);
         if (hex.length() == 1)
             sb.append('0');
         sb.append(hex);
    }
    String result = sb.toString();
    jTextArea1.setText(result);

}