Design Pattern Basic Tutorial

The Proxy Pattern is used to Provide a placeholder or surrogate for another object to control access to it Also Known As Surrogate Motivation. The proxy pattern is a person authorized placeholder to act for another person. It is work as an agent or substitute.

It has the authority to act for another. There are some situations where clients don't or can't directly reference an object, but wants to still interact with the object. A proxy object can act as the intermediary between the client and the target object.

There are several type of Proxy Pattern as follows:

1. Remote Proxy: The Remote proxy pattern of the proxy pattern is used to Provides a reference to an object which is stored on the same or different system.
2. Virtual Proxy: This is used to Allows the creation of a memory on demand for intensive object. The object will not be created until it is really needed.
3. Copy-On-Write Proxy: It is Defers from copying or cloning targeted object until client action is required it . Really it is a form of virtual proxy.
4. Protection Proxy: This proxy pattern is used to access to a target object of different level of different client.
5. Cache Proxy: This proxy pattern is used to provide the temporary storage to the results of expensive target operations so by this feature of proxy pattern more than one clients can share the results at a time.
6. Firewall Proxy: This is used for Protects targets from the bad clients.
7. Synchronization Proxy: It is used for Providing multiple accesses to an object which is on target.
8. Smart Reference Proxy: This proxy Provides the additional actions when the targeted objects are referenced like as counting to the object references number.