Behavioral Patterns

Shared Database

The Shared Database pattern describes a situation where multiple clients or applications access the same underlying database. This allows for data consistency and simplifies data sharing between different parts of a system. The primary benefit is avoiding data duplication and potential synchronization issues when many …

Fluent Interface

behavioral idiomatic

The Fluent Interface pattern enables the creation of readable and maintainable code by allowing method calls to be chained together. It achieves this by making methods return the object itself (or another builder object) instead of void. This results in a more natural and expressive syntax for configuring or building …

Saga (Orchestration)

distributed system behavioral integration

The Saga pattern manages a sequence of local transactions in a distributed system. It’s used to ensure data consistency across multiple services, especially when traditional ACID transactions aren’t feasible due to the nature of distributed environments. Instead of a single, atomic transaction, the Saga …

Promise

behavioral asynchronous

The Promise pattern addresses the complexities of asynchronous operations in programming. It provides a placeholder for a value that will be available at some point in the future, without blocking the current execution thread. Instead of directly handling the result or error of an operation, a Promise offers a clean …

Query Object

behavioral data access

The Query Object pattern encapsulates complex data retrieval logic into dedicated objects. Instead of scattering database or service queries throughout your application’s logic, you move them into these query objects. This promotes separation of concerns, making your domain models cleaner and more focused on their core …

Materialized View

behavioral performance

The Materialized View pattern is a way to optimize read performance by precomputing and storing the results of complex or frequently used queries. Instead of re-executing these queries every time they are needed, the precomputed results are retrieved directly from the materialized view, dramatically reducing latency. …

Projection

behavioral data

The Projection pattern addresses the problem of efficiently delivering only the data required by a client or use case, preventing over-fetching and improving performance. Instead of exposing the entire data model, a projector transforms the source data into a simplified data view specifically tailored for the consumer. …

Chain of Responsibility

behavioral GoF

The Chain of Responsibility is a behavioral design pattern that allows you to pass a request along a chain of handlers. Each handler decides either to process the request or to pass it to the next handler in the chain. This pattern decouples the sender of a request from its receivers, giving multiple objects the …

Event Sourcing

behavioral DDD persistence

Event Sourcing is a pattern where the state of an application is determined not by directly storing the current state, but by storing a sequence of all the changes (events) that have occurred. Instead of asking “what is the data now?” you ask “what happened then?” and rebuild the state from the …

Identity Map

behavioral data access

The Identity Map pattern ensures that each object has a unique representation in memory. It maintains a registry of objects already loaded from the database, and when an object is requested, the map checks if it already exists before retrieving it from the persistence store. This reduces memory consumption and improves …