md5.java

MD5的加密解密功能

package com.vlan.lib.web;

	public final class Md5{
		  public Md5(){};

		  /**
		   * 用于将输入的字符串经过MD5算法加密后返回结果
		   * inString   输入的字符串
		   * outString  输出的结果
		   */
		  public static String digest(String inString)
		  {
		   String outString=null;
		   try {
		     java.security.MessageDigest alg=java.security.MessageDigest.getInstance("MD5");
		     alg.update(inString.getBytes());
		     byte[] digest=alg.digest();
		     outString=byte2hex(digest);
		   } catch (java.security.NoSuchAlgorithmException ex) {
		     ex.printStackTrace();
		   }
		   return outString;
		  }

		  /**
		   * 用于将二行制转字符串
		   */
		  private static String byte2hex(byte[] b)
		    {
		     String hs="";
		     String stmp="";
		     for (int n=0;n<b.length;n++)
		      {
		       stmp=(java.lang.Integer.toHexString(b[n] & 0XFF));
		       if (stmp.length()==1) hs=hs+"0"+stmp;
		       else hs=hs+stmp;
		       if (n<b.length-1)  hs=hs+"";
		      }
		     return hs.toUpperCase();
		    }

		   /**
		   * 用于在Counsle下测试本类
		   */
		  public static void main(String args[])
		  {
			  System.out.println("beijing["+digest("beijing")+"]");
			  
		  }
}