MD5加密方法

以下代码是将一个正常编码字符串通过MD5加密处理:

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5Hex {

	/**
	 * @param args
	 */
	// MD5加密是不可逆的
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		MD5Hex mMd = new MD5Hex();
		String mRes = mMd.md5("thank");
		System.out.println("mRes__________" + mRes);
	}

	private static final char HEX_DIGITS[] = { '0', '1', '2', '3', '4', '5',
			'6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

	public static String toHexString(byte[] b) { // String to byte
		StringBuilder sb = new StringBuilder(b.length * 2);
		for (int i = 0; i < b.length; i++) {
			sb.append(HEX_DIGITS[(b[i] & 0xf0) >>> 4]);
			sb.append(HEX_DIGITS[b[i] & 0x0f]);
		}
		return sb.toString();
	}

	public String md5(String s) {
		try {
			// Create MD5 Hash
			MessageDigest digest = java.security.MessageDigest
					.getInstance("MD5");
			digest.update(s.getBytes());
			byte messageDigest[] = digest.digest();
            // 将加密后的字节以十六进制形式字符串返回
			return toHexString(messageDigest);
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}

		return "";
	}

}

另外附件一个解密MD5的网站地址:
http://www.md5.cc/