Structural design patterns are design patterns that ease the design by identifying a simple way to realize relationships between entities and are responsible for building simple and efficient class hierarchies between different classes.
Examples of Structural Patterns include:
- Adapter pattern: ‘adapts’ one interface for a class into one that a client expects.
- Adapter pipeline: Use multiple adapters for debugging purposes.
- Retrofit Interface Pattern: An adapter used as a new interface for multiple classes at the same time.
- Aggregate pattern: a version of the Composite pattern with methods for aggregation of children.
- Bridge pattern: decouple an abstraction from its implementation so that the two can vary independently.
- Tombstone: An intermediate “lookup” object contains the real location of an object.
- Composite pattern: a tree structure of objects where every object has the same interface.
- Decorator pattern: add additional functionality to a class at runtime where subclassing would result in an exponential rise of new classes.
- Extensibility pattern: a.k.a. Framework – hide complex code behind a simple interface.
- Facade pattern: create a simplified interface of an existing interface to ease usage for common tasks.
- Flyweight pattern: a large quantity of objects share a common properties object to save space.
- Marker pattern: an empty interface to associate metadata with a class.
- Pipes and filters: a chain of processes where the output of each process is the input of the next.
- Opaque pointer: a pointer to an undeclared or private type, to hide implementation details.
- Proxy pattern: a class functioning as an interface to another thing.