Glossary

Version 12.10 by chrisby on 2023/10/13 10:43

The explanations given here do not claim to be complete. They merely serve as a brief description to give an idea of the respective term. For more detailed information, the Internet should be consulted. Note that some of these technical terms are fuzzy, overlap with other terms, or have different meanings depending on the context or the people using them. This Glossary is an attempt to structure these terms in a concise manner. Be open to variations as you talk and work with other developers.

TermExplanation
Abstraction
  1. The counterpart to 'Concretion', refers to interfaces and abstract classes that define behavior (function signatures) but leave the internal operacommand-line interfacestion of these functions undefined.
  2. A higher-level, generalized unit of code. Duplication across multiple functions can be resolved by creating an 'abstraction' - a separate function containing the shared code. This adheres to the DRY principle.
AssertionPertains to an assertion function, a crucial part of testing. If the input values don't satisfy a certain condition, the test containing the assertion fails. Example: 'assertEquals(expectedResult, actualResult)'.
AwarenessA class A is aware of class B if it contains a reference to class B in its source code. If no such reference exists, class A is unaware of class B.
Best PracticesWidely accepted guidelines designed to enhance programming productivity and code quality. Adherence can prevent many potential issues.
ConcretionThe counterpart to 'abstraction', also known as 'implementation'. In OOP, refers to non-abstract classes that implement the methods of interfaces or abstract classes. A concretion provides the 'concrete' code defining the workings of these abstract functions.
Constructor InjectionA type of dependency injection in which dependencies are provided to an object through constructor arguments.
Command-Line Interface (CLI)"[...] a means of interacting with a computer program by inputting lines of text [...]".[src] For example, tools/commands used when working with a (Linux) terminal.
Component

In software architecture, a module capable of independent operation, often compiled or packaged into an executable such as a .jar or .exe file.

DaemonA program running in the background of a system, typically without a GUI.
Data StructureA class primarily meant to hold data and provide basic operations to access and manipulate that data. May contain only public fields, or private fields with associated getter and setter methods.
DependencyIn context of classes, a dependency is an object required by another object to perform its functions. Often, dependencies are provided via dependency injection.
Dependency CycleA situation where two or more classes depend on each other to be instantiated. This situation creates a circular dependency that makes object creation impossible. The dependency graph should be a directed acyclic graph rather than a cycle.
Dependency Injection (DI)A technique where an object's dependencies are provided from outside, rather than being created within the object itself.
DirtyCode that is messy, unreadable, or poorly designed. Often refers to 'quick-and-dirty' code written under time pressure.
DistributionA version of an OS packaged with specific software and configurations, designed for specific use cases. Examples: Ubuntu, Fedora, and Arch Linux, all based on Linux.
Dynamic

Pertains to behaviors or properties determined at runtime. Examples: dynamic dependencies can be replaced at runtime; dynamically-typed languages determine an object's type at runtime.

Entity

1. In object context, this signifies that two objects of the same type, even with identical field values, are still distinct entities.

2. In software architecture, refers to classes representing application data models. A banking application might have entity classes like Account, Order, Customer, or Employee.

Field InjectionA type of dependency injection where a dependency is injected directly into an object's field via reflection, bypassing encapsulation.
Functionality
Graphical User Interface (GUI)A user interface that allows users to interact with the system through graphical elements like icons, buttons, windows, and menus.
Isolation/Isolated

The opposite of integration. Isolation is the separation of a unit or component from the rest of the system in order to test, develop or understand it independently and ensure that it works correctly without external interference. For example, in unit testing, a single unit is usually tested independently of other units and is isolated from them.

Integration/Integrated

The opposite of isolation. Integration is the process of combining different software units or components to work together as a single, cohesive system.  For example, component testing is more integrated than unit testing because it involves multiple units working together. Integration testing tests the interaction between two components.

Inversion of Control (IoC)A design principle that encourages the delegation of application unit wiring to a computer algorithm that facilitates dependency injection, rather than the developer implementing this logic manually.
ModuleA distinct part of a software that encapsulates specific implementation details, such as functions, data structures, classes, interfaces, or even other modules. It exposes a concise API designed to perform specific tasks. These modules are typically crafted for reusability and improved code organization, thereby promoting a modular design.
LogicCode with non-trivial complexity. For instance, getters and setters have trivial complexity and are usually not considered 'logic'.
MagicCode that performs complex tasks while abstracting away the complexity, presenting a simple interface to the user.
Operating System (OS)The foundational system software that manages and coordinates all computer resources. Examples include Windows, MacOS, and Linux.
PainAn unpleasant experience caused by unnecessary efforts that could be mitigated with better code design.
Production CodeCode that comprises the functioning part of an application, as opposed to test code.
RollbackThe act of returning a system or data to a previous state, often using a snapshot.
RuntimeThe period when the code is being executed.
SecurityMeasures implemented to protect systems from threats, unauthorized access, and vulnerabilities. This includes, but is not limited to, authentication, authorization, and encryption.
Self-ContainmentThe ability of software to operate independently, without dependence on external services or factors. This characteristic ensures that its results are determined solely by its source code, which promotes stability and consistency.
Separation of ConcernsA design principle suggesting that each module or component should have a single responsibility or concern, enhancing clarity and maintainability.
Setter InjectionA type of dependency injection where a dependency is provided to an object through a setter method.
SnapshotA saved state of a system or data at a specific point in time. Can be used for rollbacks.
StaticPertains to behaviors or properties determined at compile time. Examples: static code analysis tools inspect source code; statically-typed languages determine an object's type at compile time.
SystemEntirety of software components designed to work together effectively in a production environment.
Test CodeCode that tests the functionality of production code. Does not contribute to the operational aspects of an application.
Test-Driven Development (TDD)A development approach where code is written in small increments, with tests defining functionality written before each coding iteration.
Test SuiteThe sum of all the test code used to check that a system meets its requirements.
UnitThe smallest testable part of an application. This is often a single class, method or module, but can also be a small cluster of tightly coupled classes or functions that together perform a specific functionality.
Virtual Machine (VM)A software emulation of a physical computer, able to run its own OS and applications as if it were a separate physical machine.
WiringThe process conducted by the IoC container to create and inject dependencies, facilitating application startup.