Reusable answers to typical issues that developers run across during the design and development phase are known as software design patterns. These patterns aid in the creation of adaptable, extendable, and maintainable software systems by offering an organized method for resolving design-related problems. This essay will examine ten popular software design patterns and go over their salient features and applications.

Common design patterns

Singleton: 

A global point of access to a class that guarantees the creation of just one instance is provided by the Singleton pattern. When you wish to give a single shared instance of a class across your application and need to restrict the number of instances of the class, this approach comes in handy. Singletons are frequently used to manage resources like thread pools and database connections.

Prototype: 

By cloning pre existing items, you may construct new ones using the Prototype pattern. You may use a prototype as a blueprint to make copies with pre-initialized properties rather than creating new objects from scratch. This style allows for dynamic runtime configuration and lowers the cost of object creation.

Builder: 

The Builder pattern allows alternative representations to be created from the same building process by separating the creation of complicated things from their representation. It gives users more control over the creation process and a methodical approach to making products. When working with items that require complex setup or have numerous configuration choices, builders are very helpful.

Factory: 

The Factory pattern gives subclasses the ability to choose which class to instantiate while still providing an interface for producing objects. It encourages loose coupling between classes and increases code flexibility by encapsulating object creation behavior. When you wish to abstract the instantiation process and have a family of related classes, you often utilize factories.

Facade: 

In a subsystem, the Facade pattern offers a single interface to a group of interfaces. By hiding the complexity of complicated subsystems with a higher-level interface, it makes them simpler. This design pattern encourages loose coupling between clients and subsystems, lowers dependencies, and improves code readability. Facades are frequently used to simplify complicated systems' or libraries' user interfaces.

Proxy: 

To manage access to another object, the Proxy pattern offers a stand-in or proxy object. Serving as a mediator, it permits the addition of new features without affecting the original object's interface. When you wish to add security checks, caching, or slow loading to an object's behavior without changing it directly, proxies come in handy.

Iterator: 

An aggregate object's elements can be accessed successively without disclosing its underlying representation thanks to the Iterator pattern. It enables consistent traversal operations by severing the client code from the collection's structure. A frequent usage for iterators is to offer a uniform interface for iterating across various kinds of collections.

Observer: 

The Observer pattern creates a one-to-many dependence between objects, allowing numerous observers to be informed whenever a subject object's state changes. It facilitates loose coupling, which encourages extensibility and modularity among objects. When several components of an event-driven system, such a graphical user interface, need to respond to changes in a common resource, observers are frequently utilized.

Mediator: 

An object that captures the interactions between a group of items is defined by the Mediator pattern. By centralizing control logic and minimizing direct connections, it encourages loose coupling between objects. When there is a complicated scenario involving several objects and you wish to avoid the complexity of direct object-to-object communication, mediators might be helpful.

State: 

When an object's internal state changes, it can use the State pattern to modify its behavior. It assigns the selection of behavior to the current state and encapsulates the various behaviors in distinct state objects. Large conditional statements are reduced in number thanks to this design, which also makes state transitions explicit and manageable. In systems where an object's internal state determines its behavior, states are frequently employed.

Conclusion:

Software design patterns offer a collection of tried-and-true answers to typical design issues, assisting programmers in building more dependable, expandable, and maintainable software systems. In this post, we looked at ten popular software design patterns and spoke about their main traits and applications.