ParseURL.java

public class ParseURL {

    static private String[] protocols = { "jdbc", "postgresql" };

    Properties parseURL(String url, Properties defaults) throws SQLException
    {
        int state = -1;
        Properties urlProps = new Properties(defaults);

        String l_urlServer = url;
        String l_urlArgs = "";

        int l_qPos = url.indexOf('?');
        if (l_qPos != -1)
        {
            l_urlServer = url.substring(0, l_qPos);
            l_urlArgs = url.substring(l_qPos + 1);
        }

        // look for an IPv6 address that is enclosed by []
        // the upcoming parsing that uses colons as identifiers can't handle
        // the colons in an IPv6 address.
        int ipv6start = l_urlServer.indexOf("[");
        int ipv6end = l_urlServer.indexOf("]");
        String ipv6address = null;
        if (ipv6start != -1 && ipv6end > ipv6start)
        {
            ipv6address = l_urlServer.substring(ipv6start + 1, ipv6end);
            l_urlServer = l_urlServer.substring(0, ipv6start) + "ipv6host" + l_urlServer.substring(ipv6end + 1);
        }

        //parse the server part of the url
        StringTokenizer st = new StringTokenizer(l_urlServer, ":/", true);
        int count;
        for (count = 0; (st.hasMoreTokens()); count++)
        {
            String token = st.nextToken();

            // PM Aug 2 1997 - Modified to allow multiple backends
            if (count <= 3)
            {
                if ((count % 2) == 1 && token.equals(":"))
                    ;
                else if ((count % 2) == 0)
                {
                    boolean found = (count == 0) ? true : false;
                    for (int tmp = 0;tmp < protocols.length;tmp++)
                    {
                        if (token.equals(protocols[tmp]))
                        {
                            // PM June 29 1997 Added this property to enable the driver
                            // to handle multiple backend protocols.
                            if (count == 2 && tmp > 0)
                            {
                                urlProps.setProperty("Protocol", token);
                                found = true;
                            }
                        }
                    }

                    if (found == false)
                        return null;
                }
                else
                    return null;
            }
            else if (count > 3)
            {
                if (count == 4 && token.equals("/"))
                    state = 0;
                else if (count == 4)
                {
                    urlProps.setProperty("PGDBNAME", token);
                    state = -2;
                }
                else if (count == 5 && state == 0 && token.equals("/"))
                    state = 1;
                else if (count == 5 && state == 0)
                    return null;
                else if (count == 6 && state == 1)
                    urlProps.setProperty("PGHOST", token);
                else if (count == 7 && token.equals(":"))
                    state = 2;
                else if (count == 8 && state == 2)
                {
                    try
                    {
                        Integer portNumber = Integer.decode(token);
                        urlProps.setProperty("PGPORT", portNumber.toString());
                    }
                    catch (Exception e)
                    {
                        return null;
                    }
                }
                else if ((count == 7 || count == 9) &&
                        (state == 1 || state == 2) && token.equals("/"))
                    state = -1;
                else if (state == -1)
                {
                    urlProps.setProperty("PGDBNAME", token);
                    state = -2;
                }
            }
        }
        if (count <= 1)
        {
            return null;
        }

        // if we extracted an IPv6 address out earlier put it back
        if (ipv6address != null)
            urlProps.setProperty("PGHOST", ipv6address);

        //parse the args part of the url
        StringTokenizer qst = new StringTokenizer(l_urlArgs, "&");
        for (count = 0; (qst.hasMoreTokens()); count++)
        {
            String token = qst.nextToken();
            int l_pos = token.indexOf('=');
            if (l_pos == -1)
            {
                urlProps.setProperty(token, "");
            }
            else
            {
                urlProps.setProperty(token.substring(0, l_pos), token.substring(l_pos + 1));
            }
        }

        return urlProps;
    }

}