A specialized port for use with PortParameter. This port is created
by an instance of PortParameter and provides values to a parameter.
Data should not be read directly from this port. Instead, the update
method of the corresponding PortParameter should be invoked. This
port is only useful if the container is opaque, however, this is not
checked.
Edward A. Lee
$Id: ParameterPort.java 70402 2014-10-23 00:52:20Z cxh $
Ptolemy II 3.0
Green (eal)
Yellow (neuendor)
The associated parameter.