加密算法SHA-1，SHA-256，SHA-512，MD2,MD5

自定义某种算法

package test;   
  
import java.security.MessageDigest;   
import java.security.NoSuchAlgorithmException;   
  
public class MD {   
  
 public static void main(String[] args) {   
  MD md = new MD();   
  System.out.println(md.encrypte("heisetoufa", "SHA-1"));// SHA-1算法   
  System.out.println(md.encrypte("heisetoufa", "SHA-256"));// SHA-256算法   
  System.out.println(md.encrypte("heisetoufa", "SHA-512"));// SHA-512算法   
     
  System.out.println(MD.encrypte("heisetoufa", "MD2"));//MD2算法   
  System.out.println(MD.encrypte("heisetoufa", "MD5"));//MD5算法   
 }   
  
 /**  
  * encrypted password based on JCA algorithm of message digest  
  *   
  * @param plainText  
  *            orginal password text  
  * @param algorithm  
  *            name of algorithm  
  * @return encrypted password  
  */  
 private static String encrypte(String plainText, String algorithm) {   
  MessageDigest md = null;   
  try {   
   md = MessageDigest.getInstance(algorithm);   
  } catch (NoSuchAlgorithmException e) {   
   e.printStackTrace();   
  }   
  md.update(plainText.getBytes());   
  byte[] b = md.digest();   
  StringBuilder output = new StringBuilder(32);   
  for (int i = 0; i < b.length; i++) {   
   String temp = Integer.toHexString(b[i] & 0xff);   
   if (temp.length() < 2) {   
    output.append("0");   
   }   
   output.append(temp);   
  }   
  return output.toString();   
 }   
}  MD5加密

package test;   
  
import java.security.MessageDigest;   
import java.security.NoSuchAlgorithmException;   
  
public class MD5 {   
  
 public static void main(String[] args)   
 {   
  MD5 md5 = new MD5();   
  System.out.println(md5.md5("heisetoufa"));   
//  System.out.println(md5.md5("heisetoufa").length());   
 }   
  
 public String md5(String source) {   
  String dest = null;   
  try {   
   MessageDigest md5 = MessageDigest.getInstance("MD5");   
   char[] charArray = source.toCharArray();   
   byte[] byteArray = new byte[charArray.length];   
   for (int i = 0; i < charArray.length; i++)   
    byteArray[i] = (byte) charArray[i];   
   byte[] md5Bytes = md5.digest(byteArray);   
   StringBuffer hexValue = new StringBuffer();   
   for (int i = 0; i < md5Bytes.length; i++) {   
    int val = ((int) md5Bytes[i]) & 0xff;   
    if (val < 16)   
     hexValue.append("0");   
    hexValue.append(Integer.toHexString(val));   
   }   
   dest = hexValue.toString();   
  
  } catch (NoSuchAlgorithmException e) {   
   e.printStackTrace();   
  }   
  return dest;   
 }   
  
  
}