Proxy provides a surrogate or placeholder for another object in order to control access to it.
Pattern type - Structural
Proxy is about controlling an access.
Variations of pattern:
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Remote proxy - used for resources which are "outside". Proxy is responsible for dealing with connection to that remote resource.
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Virtual proxy - controls access to a resource which is expensive to create.
It allows to interface with resource when it's really needed (lazy evaluation + cache). -
Protection proxy - passes only requests from authorised clients.
Proxy pattern implements additional behaviour to control access to some resource.
Proxy class has to implement the same interface as targeted object.
AssetManager class provides some Asset objects.
Access to this manager is controlled via AssetManagerAccessProxy.
Only authorised clients are able to access assets.