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Practical guides on software architecture, system design, developer tools, tutorials, and the technology trends shaping how we build.
Latest from Debug
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Incredible – 05 Prototype Pattern
Prototype Pattern in Java: Cloning Instead of Constructing The Problem Sometimes creating a new object from scratch is expensive (deep object graphs, database lookups, complex configuration), but you already have a similar object at hand. The Prototype pattern lets you copy existing objects without making your code dependent on their concrete classes. Diagram Java Example Usage — start from a base plan…
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Incredible – 04 Builder Pattern
Builder Pattern in Java: Constructing Complex Objects Step by Step The Problem When an object has many optional fields, telescoping constructors (new Foo(a, b, null, null, c, …)) become unreadable and error-prone. The Builder pattern separates the construction of a complex object from its representation, letting you build it step by step. Diagram Java Example Usage: Quarkus Example Builders pair…
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03 – Abstract Factory Pattern
Abstract Factory Pattern in Java: Families of Related Objects The Problem Sometimes you need to create families of related objects that must stay consistent with each other — for example, UI components for different themes, or payment gateway objects for different regions. Abstract Factory provides an interface for creating families of related objects without specifying their concrete classes. Diagram Java Example Quarkus…
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02 – Factory Method Pattern
Factory Method Pattern in Java: Delegating Object Creation The Problem You need to create objects, but the exact type to instantiate should be decided by subclasses or configuration — not hardcoded with new. The Factory Method pattern defines an interface for creating an object, letting subclasses decide which class to instantiate. Diagram Java Example Quarkus Example In Quarkus, Factory Method often becomes…
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01 – Singleton Pattern
Singleton Pattern in Java: Ensuring a Single Instance The Problem Sometimes you need exactly one instance of a class across your whole application — a configuration manager, a connection pool, a logger. The Singleton pattern guarantees a class has only one instance and provides a global point of access to it. Diagram Java Example (thread-safe, lazy) The classic double-checked locking is safe…