Java MD5 encryption Implementation code _java

The following diagram is the first to understand the MD5 encryption implementation, as follows

Package COM.PB;
Import java.io.UnsupportedEncodingException;
Import Java.security.MessageDigest;
Import java.security.NoSuchAlgorithmException;

Import Java.util.Scanner; * * Verify MD5 * 1. Initialize MessageDigest Information Digest Object * 2. Pass in the string update summary information that needs to be computed * 3. Calculation Information Summary * 4. Convert byte[] to 32-bit with 16-digit String */public class MD5 {* * * generate MD5 have incoming parameter string */public void generateMD5 (string input) {try {//1. Initialize messagedigest information pick
       To object, and specifies that the MD5 can be messagedigest md=messagedigest.getinstance ("MD5") without any case. 2. Pass in the string update summary information that needs to be computed, incoming as byte array byte[],///convert string to byte array use GetBytes () method to complete//specify when its character encoding is Utf-8 md.update (input.get
       Bytes ("Utf-8"));
       3. Calculation Information Digest Digest () method//Return value is byte array byte [] hashcode=md.digest ();
      4. Convert byte[] to a 32-bit 16-string/Declaration StringBuffer object to store the final value StringBuffer sb=new stringbuffer (); Traversal byte array for (byte B:hashcode) {//array content converted to 16, Sb.append (Character.fordigit (B>>4&0XF, 16))
        ; 32-bit 16-Sb.ap for 2 timesPend (Character.fordigit (B&0XF, 16));
    SYSTEM.OUT.PRINTLN ("The result of the encryption is:" +sb.tostring ());
    catch (NoSuchAlgorithmException e) {//TODO auto-generated catch block E.printstacktrace ();
    catch (Unsupportedencodingexception e) {//TODO auto-generated catch block E.printstacktrace ();
    The public static void main (string[] args) {//Declares the object of the cryptographic MD5 class MD5 md5=new MD5 ();
    Use Scanner to enter a character Scanner scanner=new Scanner (system.in);
    System.out.println ("Please enter the content to be encrypted:");
    String input = Scanner.nextline ();

  Call encryption Method MD5.GENERATEMD5 (input);
 }
  
}

Results:

Please enter the content to be encrypted:
Learn the MD5 encryption process
The result of encryption is: b826cdac46f01dcc8ccc60a76cebf858

Second paragraph code:

Package test.md5;

Import Java.security.MessageDigest; public class Md5util {public final static string MD5 (string s) {char hexdigits[]={' 0 ', ' 1 ', ' 2 ', ' 3 ', ' 4 ', ' 5 ', ' 6 ', ' 7 ',    

    ' 8 ', ' 9 ', ' A ', ' B ', ' C ', ' D ', ' E ', ' F '};
      try {byte[] btinput = S.getbytes ();
      Obtain the MessageDigest object messagedigest mdinst = messagedigest.getinstance ("MD5") of MD5 Digest algorithm;
      Use the specified Byte update digest mdinst.update (Btinput);
      Get ciphertext byte[] MD = Mdinst.digest ();
      Converts cipher text into a 16-binary string form int j = md.length;
      Char str[] = new CHAR[J * 2];
      int k = 0;
        for (int i = 0; i < J; i++) {byte byte0 = md[i];
        str[k++] = hexdigits[byte0 >>> 4 & 0xf];
      str[k++] = hexdigits[byte0 & 0xf];
    return new String (str);
      catch (Exception e) {e.printstacktrace ();
    return null;
    } public static void Main (string[] args) {System.out.println (Md5util.md5 ("20121221")); System.out.println (MD5UTIL.MD5 ("Encryption"));
 }
}

Third paragraph code: MD5 encryption algorithm Java implementation

package other;
Import Java.security.MessageDigest;
Import java.security.NoSuchAlgorithmException; * * * MD5 Algorithm */public class MD5 {//global array private final static string[] strdigits = {"0", "1", "2", "3", "4", "5"

  , "6", "7", "8", "9", "a", "B", "C", "D", "E", "F"};
    Public MD5 () {}//return form is numeric with string private static string bytetoarraystring (byte bbyte) {int iRet = Bbyte;
    System.out.println ("iret=" +iret);
    if (IRet < 0) {IRet = 256;
    int iD1 = IRET/16;
    int iD2 = iRet% 16;
  return STRDIGITS[ID1] + STRDIGITS[ID2];
    The//Return form is only numeric private static String Bytetonum (byte bbyte) {int iRet = Bbyte;
    System.out.println ("iret1=" + iRet);
    if (IRet < 0) {IRet = 256;
  Return string.valueof (IRet);
    //Convert byte array to 16 binary string private static String bytetostring (byte[] bbyte) {StringBuffer sbuffer = new StringBuffer (); for (int i = 0; i < bbyte.length i++) {sbuffer.append (bytetoarraystRing (Bbyte[i]));
  return sbuffer.tostring ();
    public static string Getmd5code (String strobj) {string resultstring = null;
      try {resultstring = new String (strobj);
      MessageDigest MD = messagedigest.getinstance ("MD5");
    Md.digest () The function returns a byte array resultstring = Bytetostring (Md.digest (Strobj.getbytes ()) that holds the result of the hash value;
    catch (NoSuchAlgorithmException ex) {ex.printstacktrace ();
  return resultstring;
    public static void Main (string[] args) {MD5 getMD5 = new MD5 ();
  System.out.println (Getmd5.getmd5code ("000000"));
 }
}

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