Provides a surrogate or place holder for another object to control access to it.
Category:
Structural
UML Diagram:
Description of the Demonstration:
In this simulation a GumballMachine is communicating over a network with a
remote GumballMonitor. Because of the overhead required in network communications
rather than requiring the GumballMachine and the GumballMonitor to implement
those time and resource heavy features they communicate with a proxy for the other.
A GumballMachineProxy handles the networking for the GumballMonitor. To the
GumballMonitor communicating with the GumballMachineProxy appears to be the same as
communicating directly with the GumballMachine. On the other end of the
connection a GumballMonitorProxy communicates with the GumballMachine. To the
GumballMachine communicating with the GumballMonitorProxy appears to be the same
as communicating directly with the GumballMonitor.
Note that in this demonstration the Proxys are both subclasses of GumballProxy
and the appropriate GumballMachine or GumballMonitor. This makes the internal
references in ProxyMain simpler.
Code:
Click here to download a
zip file containing all the source files and an executable of the
Demonstration. See the _ReadMe.txt file in the zip.
