proxy Comparison Table

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proxy comparison table

Subject have solution have related patterns have references have context have forces have problem has definition have antipatterns is a subtopic of is a kind of is an instance of

design pattern zero or more related design patterns one or more references which indicate who developed or inspired a pattern a context one or more forces a sentence or two explaining the main difficulty being tackled A pattern useful for the design of software zero or more antipatterns - solutions that are inferior or do not work in this context with the reason for their rejection 6.1 - Introduction to Patterns pattern

proxy
Create a simpler version of the ŤHeavyWeightť class.
We will call this simpler version a ŤProxyť.
The ŤProxyť has the same interface as the ŤHeavyWeightť, so programmers can declare variables without caring whether a ŤProxyť or its ŤHeavyWeightť version will be put in the variable.
several patterns that obtain their power from delegating responsibilities to other classes, hence it uses the Delegation pattern one of the Gang of Four patterns
There may be a time-delay and a complex mechanism involved in creating instances of heavyweight classes.
You want all the objects in a domain model to be available for programs to use when they execute a system's various responsibilities
It is important for many objects to persist from run to run of the same program
in a large system it would be impractical for all the objects to be loaded into memory whenever a program starts
It would be ideal to be able to program the application as if all the objects were located in memory
How can you reduce the need to create instances of a heavyweight class? In particular, how can you reduce the need to load large numbers of them from a database or server, when not all of them will be needed? A related problem is this: If you load one object from a database or server, how can you avoid loading all the other objects that are linked to it. A pattern found in which a lightweight object stands in place of a heavyweight object that has the same interface. It transparently loads the heavyweight object when needed Instead of using proxy objects, beginner designers often scatter complex code around their application to load objects from databases. A strategy that only works for very small systems is to load the whole database into memory when the program starts. 6.12 - The Proxy Pattern design pattern

Subject	have solution	have related patterns	have references	have context	have forces	have problem	has definition	have antipatterns	is a subtopic of	is a kind of	is an instance of
design pattern		zero or more related design patterns	one or more references which indicate who developed or inspired a pattern	a context	one or more forces	a sentence or two explaining the main difficulty being tackled	A pattern useful for the design of software	zero or more antipatterns - solutions that are inferior or do not work in this context with the reason for their rejection	6.1 - Introduction to Patterns	pattern
proxy	Create a simpler version of the ŤHeavyWeightť class. We will call this simpler version a ŤProxyť. The ŤProxyť has the same interface as the ŤHeavyWeightť, so programmers can declare variables without caring whether a ŤProxyť or its ŤHeavyWeightť version will be put in the variable.	several patterns that obtain their power from delegating responsibilities to other classes, hence it uses the Delegation pattern	one of the Gang of Four patterns	There may be a time-delay and a complex mechanism involved in creating instances of heavyweight classes.	You want all the objects in a domain model to be available for programs to use when they execute a system's various responsibilities It is important for many objects to persist from run to run of the same program in a large system it would be impractical for all the objects to be loaded into memory whenever a program starts It would be ideal to be able to program the application as if all the objects were located in memory	How can you reduce the need to create instances of a heavyweight class? In particular, how can you reduce the need to load large numbers of them from a database or server, when not all of them will be needed? A related problem is this: If you load one object from a database or server, how can you avoid loading all the other objects that are linked to it.	A pattern found in which a lightweight object stands in place of a heavyweight object that has the same interface. It transparently loads the heavyweight object when needed	Instead of using proxy objects, beginner designers often scatter complex code around their application to load objects from databases. A strategy that only works for very small systems is to load the whole database into memory when the program starts.	6.12 - The Proxy Pattern		design pattern

Next design pattern: read-only interface Up: design pattern Previous design pattern: player-role