uri.java

这是linux下ssl vpn的实现程序

      while (index < uriSpecLen) {
        testChar = uriSpec.charAt(index);

        if (testChar == '/' || testChar == '?' || testChar == '#') {
          break;
        }

        index++;
      }

      // if we found authority, parse it out, otherwise we set the
      // host to empty string
      if (index > startPos) {
        initializeAuthority(uriSpec.substring(startPos, index));
      }
      else {
        m_host = "";
      }
    }

    initializePath(uriSpec.substring(index));

    // Resolve relative URI to base URI - see RFC 2396 Section 5.2
    // In some cases, it might make more sense to throw an exception
    // (when scheme is specified is the string spec and the base URI
    // is also specified, for example), but we're just following the
    // RFC specifications
    if (p_base != null) {

      // check to see if this is the current doc - RFC 2396 5.2 #2
      // note that this is slightly different from the RFC spec in that
      // we don't include the check for query string being null
      // - this handles cases where the urispec is just a query
      // string or a fragment (e.g. "?y" or "#s") -
      // see <http://www.ics.uci.edu/~fielding/url/test1.html> which
      // identified this as a bug in the RFC
      if (m_path.length() == 0 && m_scheme == null && m_host == null) {
        m_scheme = p_base.getScheme();
        m_userinfo = p_base.getUserinfo();
        m_host = p_base.getHost();
        m_port = p_base.getPort();
        m_path = p_base.getPath();

        if (m_queryString == null) {
          m_queryString = p_base.getQueryString();
        }

        return;
      }

      // check for scheme - RFC 2396 5.2 #3
      // if we found a scheme, it means absolute URI, so we're done
      if (m_scheme == null) {
        m_scheme = p_base.getScheme();
      }
      else {
        return;
      }

      // check for authority - RFC 2396 5.2 #4
      // if we found a host, then we've got a network path, so we're done
      if (m_host == null) {
        m_userinfo = p_base.getUserinfo();
        m_host = p_base.getHost();
        m_port = p_base.getPort();
      }
      else {
        return;
      }

      // check for absolute path - RFC 2396 5.2 #5
      if (m_path.length() > 0 && m_path.startsWith("/")) {
        return;
      }

      // if we get to this point, we need to resolve relative path
      // RFC 2396 5.2 #6
      String path = new String();
      String basePath = p_base.getPath();

      // 6a - get all but the last segment of the base URI path
      if (basePath != null) {
        int lastSlash = basePath.lastIndexOf('/');

        if (lastSlash != -1) {
          path = basePath.substring(0, lastSlash + 1);
        }
      }

      // 6b - append the relative URI path
      path = path.concat(m_path);

      // 6c - remove all "./" where "." is a complete path segment
      index = -1;

      while ( (index = path.indexOf("/./")) != -1) {
        path = path.substring(0, index + 1).concat(path.substring(index + 3));
      }

      // 6d - remove "." if path ends with "." as a complete path segment
      if (path.endsWith("/.")) {
        path = path.substring(0, path.length() - 1);
      }

      // 6e - remove all "<segment>/../" where "<segment>" is a complete
      // path segment not equal to ".."
      index = -1;

      int segIndex = -1;
      String tempString = null;

      while ( (index = path.indexOf("/../")) > 0) {
        tempString = path.substring(0, path.indexOf("/../"));
        segIndex = tempString.lastIndexOf('/');

        if (segIndex != -1) {
          if (!tempString.substring(segIndex++).equals("..")) {
            path = path.substring(0, segIndex).concat(path.substring(index + 4));
          }
        }
      }

      // 6f - remove ending "<segment>/.." where "<segment>" is a
      // complete path segment
      if (path.endsWith("/..")) {
        tempString = path.substring(0, path.length() - 3);
        segIndex = tempString.lastIndexOf('/');

        if (segIndex != -1) {
          path = path.substring(0, segIndex + 1);
        }
      }

      m_path = path;
    }
  }

  /**
   * Initialize the scheme for this URI from a URI string spec.
   *
   * @param p_uriSpec the URI specification (cannot be null)
   *
   * @throws MalformedURIException if URI does not have a conformant scheme
   */
  private void initializeScheme(String p_uriSpec) throws MalformedURIException {

    int uriSpecLen = p_uriSpec.length();
    int index = 0;
    String scheme = null;
    char testChar = '\0';

    while (index < uriSpecLen) {
      testChar = p_uriSpec.charAt(index);

      if (testChar == ':' || testChar == '/' || testChar == '?' ||
          testChar == '#') {
        break;
      }

      index++;
    }

    scheme = p_uriSpec.substring(0, index);

    if (scheme.length() == 0) {
      throw new MalformedURIException("No scheme found in URI.");
    }
    else {
      setScheme(scheme);
    }
  }

  /**
   * Initialize the authority (userinfo, host and port) for this URI from a URI string spec.
   *
   * @param p_uriSpec the URI specification (cannot be null)
   *
   * @throws MalformedURIException if p_uriSpec violates syntax rules
   */
  private void initializeAuthority(String p_uriSpec) throws
      MalformedURIException {

    int index = 0;
    int start = 0;
    int end = p_uriSpec.length();
    char testChar = '\0';
    String userinfo = null;

    // userinfo is everything up @
    if (p_uriSpec.indexOf('@', start) != -1) {
      while (index < end) {
        testChar = p_uriSpec.charAt(index);

        if (testChar == '@') {
          break;
        }

        index++;
      }

      userinfo = p_uriSpec.substring(start, index);

      index++;
    }

    // host is everything up to ':'
    String host = null;

    start = index;

    while (index < end) {
      testChar = p_uriSpec.charAt(index);

      if (testChar == ':') {
        break;
      }

      index++;
    }

    host = p_uriSpec.substring(start, index);

    int port = -1;

    if (host.length() > 0) {

      // port
      if (testChar == ':') {
        index++;

        start = index;

        while (index < end) {
          index++;
        }

        String portStr = p_uriSpec.substring(start, index);

        if (portStr.length() > 0) {
          for (int i = 0; i < portStr.length(); i++) {
            if (!isDigit(portStr.charAt(i))) {
              throw new MalformedURIException(portStr +
                  " is invalid. Port should only contain digits!");
            }
          }

          try {
            port = Integer.parseInt(portStr);
          }
          catch (NumberFormatException nfe) {

            // can't happen
          }
        }
      }
    }

    setHost(host);
    setPort(port);
    setUserinfo(userinfo);
  }

  /**
   * Initialize the path for this URI from a URI string spec.
   *
   * @param p_uriSpec the URI specification (cannot be null)
   *
   * @throws MalformedURIException if p_uriSpec violates syntax rules
   */
  private void initializePath(String p_uriSpec) throws MalformedURIException {

    if (p_uriSpec == null) {
      throw new MalformedURIException(
          "Cannot initialize path from null string!");
    }

    int index = 0;
    int start = 0;
    int end = p_uriSpec.length();
    char testChar = '\0';

    // path - everything up to query string or fragment
    while (index < end) {
      testChar = p_uriSpec.charAt(index);

      if (testChar == '?' || testChar == '#') {
        break;
      }

      // check for valid escape sequence
      if (testChar == '%') {
        if (index + 2 >= end || !isHex(p_uriSpec.charAt(index + 1)) ||
            !isHex(p_uriSpec.charAt(index + 2))) {
          throw new MalformedURIException(
              "Path contains invalid escape sequence!");
        }
      }
// TODO NOTE Thsi is removed as it was throwing exceptions against certain characters which should have been allowed.
//      else
//      if (!isReservedCharacter(testChar) && !isUnreservedCharacter(testChar)) {
//        if ('\\' != testChar) {
//          throw new MalformedURIException("Path contains invalid character: "
//                                          + testChar);
//        }
//      }

      index++;
    }

    m_path = p_uriSpec.substring(start, index);

    // query - starts with ? and up to fragment or end
    if (testChar == '?') {
      index++;

      start = index;

      while (index < end) {
        testChar = p_uriSpec.charAt(index);

        if (testChar == '#') {
          break;
        }

        if (testChar == '%') {
          if (index + 2 >= end || !isHex(p_uriSpec.charAt(index + 1)) ||
              !isHex(p_uriSpec.charAt(index + 2))) {
            throw new MalformedURIException(
                "Query string contains invalid escape sequence!");
          }
        }
        else
        if (!isReservedCharacter(testChar) && !isUnreservedCharacter(testChar)) {
          throw new MalformedURIException(
              "Query string contains invalid character:" + testChar);
        }

        index++;
      }

      m_queryString = p_uriSpec.substring(start, index);
    }

    // fragment - starts with #
    if (testChar == '#') {
      index++;

      start = index;

      while (index < end) {
        testChar = p_uriSpec.charAt(index);

        if (testChar == '%') {
          if (index + 2 >= end || !isHex(p_uriSpec.charAt(index + 1)) ||
              !isHex(p_uriSpec.charAt(index + 2))) {
            throw new MalformedURIException(
                "Fragment contains invalid escape sequence!");
          }
        }
        else
        if (!isReservedCharacter(testChar) && !isUnreservedCharacter(testChar)) {
          throw new MalformedURIException(
              "Fragment contains invalid character:" + testChar);
        }

        index++;
      }

      m_fragment = p_uriSpec.substring(start, index);
    }