java byte数组和16进制互转 非原创

 byte数组转16进制

public static String byte2hex(byte[] b){
    StringBuffer sb = new StringBuffer();
    String stmp = "";
    for (int n = 0; n < b.length; n++) {
        stmp = Integer.toHexString(b[n] & 0XFF);
        if (stmp.length() == 1) {
            sb.append("0" + stmp);
        } else {
            sb.append(stmp);
        }
    }
    return sb.toString();
 }

16进制转byte数组

public static byte[] hex2byte(String str) {
    if (str == null)
        return null;
    str = str.trim();
    int len = str.length();
    if (len == 0 || len % 2 == 1)
        return null;
    byte[] b = new byte[len / 2];
    try {
        for (int i = 0; i < str.length(); i += 2) {
            b[i / 2] = (byte) Integer.decode("0X" + str.substring(i, i + 2)).intValue();
        }
        return b;
    } catch (Exception e) {
        return null;
    }
  }