Method fromString

guava/src/com/google/common/net/HostAndPort.java:168–202

Split a freeform string into a host and port, without strict validation. <p>Note that the host-only formats will leave the port field undefined. You can use {@link #withDefaultPort(int)} to patch in a default value. @param hostPortString the input string to parse. @return if parsing was successful

(String hostPortString)

   * @throws IllegalArgumentException if nothing meaningful could be parsed.
   */
  @CanIgnoreReturnValue // TODO(b/219820829): consider removing
  public static HostAndPort fromString(String hostPortString) {
    checkNotNull(hostPortString);
    String host;
    String portString = null;
    boolean hasBracketlessColons = false;

    if (hostPortString.startsWith("[")) {
      String[] hostAndPort = getHostAndPortFromBracketedHost(hostPortString);
      host = hostAndPort[0];
      portString = hostAndPort[1];
    } else {
      int colonPos = hostPortString.indexOf(':');
      if (colonPos >= 0 && hostPortString.indexOf(':', colonPos + 1) == -1) {
        // Exactly 1 colon. Split into host:port.
        host = hostPortString.substring(0, colonPos);
        portString = hostPortString.substring(colonPos + 1);
      } else {
        // 0 or 2+ colons. Bare hostname or IPv6 literal.
        host = hostPortString;
        hasBracketlessColons = colonPos >= 0;
      }
    }

    Integer port;
    if (isNullOrEmpty(portString)) {
      port = NO_PORT;
    } else {
      port = Ints.tryParse(portString);
      checkArgument(port != null, "Unparseable port number: %s", hostPortString);
      checkArgument(isValidPort(port), "Port number out of range: %s", hostPortString);
    }

    return new HostAndPort(host, port, hasBracketlessColons);
  }

  /**
   * Parses a bracketed host-port string, throwing IllegalArgumentException if parsing fails.