Behavioral Patterns

Read-Write Lock

The Read-Write Lock pattern allows multiple readers to access a shared resource concurrently, but requires exclusive access for writers. This is in contrast to a traditional mutex, which only allows one thread to access the resource at a time, regardless of whether it’s reading or writing. By allowing concurrent …

Repository

DDD behavioral

The Repository pattern provides an abstraction layer between the domain logic and the data access layer. It encapsulates the complexities of data access, allowing the domain to work with objects without knowing how they are stored or retrieved. This promotes loose coupling, making the application easier to test, …

Routing Slip

behavioral message

The Routing Slip pattern facilitates the sequential passing of a request through a chain of responsibility. Each handler in the chain examines the request and either processes it or forwards it to the next handler. Unlike the Chain of Responsibility pattern, the order in which handlers process the request is …

Scheduler

behavioral concurrency

The Scheduler pattern provides a mechanism for executing tasks at specific times or after defined intervals. It decouples task execution from the task definition, allowing for flexible and dynamic scheduling of operations. A central scheduler component manages a queue of tasks, each associated with a time or trigger, …

Single Table Inheritance

behavioral ORM DDD

Single Table Inheritance is a strategy for representing a class hierarchy in a relational database using only one table for all classes in the hierarchy. A “type” column (or discriminator) is added to the table to indicate the specific class of each record. This approach simplifies querying and joins compared to other …

Snapshot

behavioral memory management

The Snapshot pattern captures the internal state of an object at a particular point in time, allowing it to be restored to that state later. This is achieved by creating a “snapshot” or “memento” of the object’s state, which is then stored by a separate “caretaker” object. The …

Specification

behavioral DDD

The Specification pattern encapsulates business rules in objects, allowing for dynamic combinations and reuse. It’s a way to separate complex logic concerning data from the objects that hold that data. This enables you to define a variety of rules, combine them, and then apply these rules to objects without directly …

State

behavioral OOA

The State pattern allows an object to alter its behavior when its internal state changes. This pattern avoids the use of large conditional statements (like if/else or switch) that often become unwieldy and difficult to maintain when dealing with complex state-dependent logic. Instead, each state is represented by a …

Store-and-Forward

behavioral communication

The Store-and-Forward pattern is a communication paradigm where an intermediary component receives a complete message from a sender, stores it, and then forwards it to the intended recipient. This decoupling allows the sender and receiver to operate independently, even if they are not simultaneously available. The …

Strangler Fig

behavioral refactoring legacy

The Strangler Fig pattern is a refactoring technique used to incrementally migrate a legacy system to a new architecture. Instead of a risky “big bang” rewrite, the pattern advocates for gradually replacing functionality by building a new system around the old one. As the new system gains more responsibility, the old …