Chapter 15. The Proxy Pattern
The Proxy pattern is used to represent with a simpler object an object that is complex or time-consuming to create. If creating an object is expensive in time or computer resources, a Proxy allows you to postpone this creation until you need the actual object. A Proxy usually has the same methods as the full object that it represents. Once that full object is loaded, the Proxy passes on the method calls to the full object.
There are several cases where a Proxy can be useful:
If an object, such as a large image, takes a long time to load
If the object is on a remote machine and loading it over the network might be slow, especially during peak network load periods
If the object has limited access rights. The proxy can ...