
Port |
ptolemy.kernel.Port |
A Port is the interface of an Entity to any number of Relations.
Normally, a Port is contained by an Entity, although a port
may exist with no container. The role of a port is to aggregate
a set of links to relations. Thus, for example, to represent
a directed graph, entities can be created with two ports, one for
incoming arcs and one for outgoing arcs. More generally, the arcs
to an entity may be divided into any number of subsets, with one port
representing each subset.
A Port can link to any instance of Relation. Derived classes may wish
to constrain links to a subclass of Relation. To do this, subclasses
should override the protected method _checkLink(Relation) to
throw an exception if its argument is a relation that is not of the
appropriate subclass. Similarly, if a subclass wishes to constrain
the containers of the port to be of a subclass of Entity, they should
override the protected method _checkContainer(Entity).
Author(s): Mudit Goel, Edward A. Lee, Jie Liu
Version:$Id: Port.java,v 1.167 2005/10/24 19:09:11 cxh Exp $
Pt.Proposed Rating:Green (eal)
Pt.Accepted Rating:Green (cxh)