constructor

/**
     * Constructor with a raw status line.
     *
     * @param line
     *         A status line.
     *
     * @throws NullPointerException
     *         {@code line} is {@code null}
     *
     * @throws IllegalArgumentException
     *         The number of elements in {@code line} is less than 2.
     *
     * @throws NumberFormatException
     *         Failed to parse the second element in {@code line}
     *         as an integer.
     */
    StatusLine(String line)
    {
        // HTTP-Version Status-Code Reason-Phrase
        String[] elements = line.split(" +", 3);

        if (elements.length < 2)
        {
            throw new IllegalArgumentException();
        }

        mHttpVersion  = elements[0];
        mStatusCode   = Integer.parseInt(elements[1]);
        mReasonPhrase = (elements.length == 3) ? elements[2] : null;
        mString       = line;
    }