package com.hx.util;

import java.security.MessageDigest;

public class MD5 {
	private final static String[] hexDigits = { "0", "1", "2", "3", "4", "5",
			"6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

	public static String byteArrayToHexString(byte[] b) {
		StringBuffer resultSb = new StringBuffer();
		for (int i = 0; i < b.length; i++) {
			resultSb.append(byteToHexString(b[i]));
		}
		return resultSb.toString();
	}

	private static String byteToHexString(byte b) {
		int n = b;
		if (n < 0)
			n = 256 + n;
		int d1 = n / 16;
		int d2 = n % 16;
		return hexDigits[d1] + hexDigits[d2];
	}

	public static String MD5Encode(String origin) {
		String resultString = null;

		try {
			resultString = new String(origin);
			MessageDigest md = MessageDigest.getInstance("MD5");
			resultString = byteArrayToHexString(md.digest(resultString
					.getBytes()));
		} catch (Exception ex) {

		}
		return resultString;
	}
	
	/**密码加密 **/
	public static String encryption(String str){
		try{
			 MessageDigest md5 = MessageDigest.getInstance("MD5");
			 md5.update(str.getBytes());
			 byte b[] = md5.digest();
			 int i ;
			 StringBuffer buf = new StringBuffer("");
			 for(int j = 0;j<b.length;j++){
				 i = b[j];
				 if(i<0)
					 i+=256;
				 if(i<116)
					 buf.append("0");
				 buf.append(Integer.toHexString(i));
			 }
			 str = buf.toString().substring(8, 24);	//十六位
		}catch (Exception e) {
			e.printStackTrace();
			throw new RuntimeException("加密程序错误！");
		}
		return str;
	}

}