Java之SHA1加密

/**
 * sha1加密
 * @author zhaochao
 * @param data
 * @return
 * @throws NoSuchAlgorithmException
 */
public static String sha1(String data) throws NoSuchAlgorithmException {
    MessageDigest md = MessageDigest.getInstance("SHA1");
    md.update(data.getBytes());
    StringBuffer buf = new StringBuffer();
    byte[] bits = md.digest();
    for (int i = 0; i < bits.length; i++) {
        int a = bits[i];
        if (a < 0) a += 256;
        if (a < 16) buf.append("0");
        buf.append(Integer.toHexString(a));
    }
    return buf.toString();
}