MD5,SHA-1,SHA-256摘要加解密

/**
 * 对字符串加密,加密算法使用MD5,SHA-1,SHA-256,默认使用SHA-256
 *
 * @param strSrc 要加密的字符串
 * @return
 */
public static String Encrypt(String strSrc, String encName) {
    MessageDigest md = null;
    String strDes = null;
    byte[] bt = strSrc.getBytes();
    try {  
        if (encName == null || encName.equals("")) {
            encName = "SHA-256";
        }
        md = MessageDigest.getInstance(encName );
        md.update(bt);
        strDes = bytes2Hex(md.digest());
    } catch (Exception e) {
        return null;
    }
    return strDes;
}

public static String bytes2Hex(byte[] bts) {
    String des = "";
    String tmp = null;
    for (int i = 0; i < bts.length; i++) {
        tmp = (Integer.toHexString(bts[i] & 0xFF));
        if (tmp.length() == 1) {
            des += "0";
        }
        des += tmp;
    }
    return des;
}