Accessor: net/UDPSocketListener


This accessor listens for UDP (datagram) messages on the specified host interface and port. If the value of the port input is initially negative, then this accessor waits until it receives a non-negative port input before initiating listening. Otherwise, it begins listening during initialization. If at any time during execution it receives a port input, then it will close any open socket and, if the new port value is non-negative, open a new socket to the current host and port.

When the connection is established, a true boolean is sent to the listening output. If the connection is broken during execution, then a false boolean is sent to the listening output. The swarmlet could respond to this by retrying to connect (send an event to the port input).

The receive type can be any of those supported by the host. The list of supported types will be provided as options for the and receiveType parameter. For the Ptolemy II host, these include at least 'string', 'number', 'image', and a variety of numeric types.

Note that UDP, unlike TCP, has the notion of a "message" (a datagram). A message can contain more than one byte. The receiveType determines the type of the elements of the output of this accessor.

  • $$Id$$
  • Hokeun Kim and Edward A. Lee, Contributor: Christopher Brooks
Name Type Description
listeningAddress string The interface to listen on for incoming messages. This defaults to "", which means to listen on all network interfaces.
listeningPort int The port to listen on for incoming messages. This defaults to 8084.
Name Type Description
message The received message as a raw byte array.
listening boolean True to indicate that listening has begun, false to indicate that it has stopped.
Name Type Description
receiveType string See above.