java實現的MD5算法

MD5算法實現如下：

 

public String md5(String str) {
		try {
			java.security.MessageDigest md5 = java.security.MessageDigest.getInstance("MD5");

			char[] charArray = str.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));
			}

			return hexValue.toString();
		} catch (java.security.NoSuchAlgorithmException e) {
			e.printStackTrace();
		}

		return "";
	}