Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [patterns-and-practices]

Design patterns (repeatable solutions to commonly occurring problems) and best practices in software engineering

161
votes
11answers
26k views

What happened to the “Surgical Team” pattern from “The Mythical Man-Month”?

Years ago, when I read The Mythical Man-Month, I found lots of stuff which I already knew from other sources. However, there were also new things in there, despite the book being from 1975. One of ...
108
votes
13answers
9k views

Exception vs empty result set when the inputs are technically valid, but unsatisfiable

I'm developing a library intended for public release. It contains various methods for operating on sets of objects - generating, inspecting, partitioning and projecting the sets into new forms. In ...
84
votes
6answers
17k views

Is it bad practice to enforce an execution order for unit tests?

I am writing tests for a project that consists of multiple submodules. Each test case that I have written runs independent of each other and I clear all data between tests. Even though the tests run ...
79
votes
2answers
12k views

Are there any OO-principles that are practically applicable for Javascript?

Javascript is a prototype-based object oriented language but can become class-based in a variety of ways, either by: Writing the functions to be used as classes by yourself Use a nifty class system ...
66
votes
4answers
20k views

Developing a feature which sole purpose to be taken out? [closed]

What is the name of the pattern in which individual contributors (programmers/designers) developed an artifact for the sole purpose is to serve as a diversion so that management can remove that ...
55
votes
4answers
32k views

When and for what purposes should the const keyword be used in C for variables?

While getting my code reviewed here the issue of using the const keyword came up. I understand that it is used for implementing read-only behaviour on variables. I am confused about what are the ...
54
votes
8answers
8k views

Term (or “pattern”?) for “Do something if it's not already done” [closed]

Sounds pretty basic, I know, but I recently had a colleague tell me that a method called startHttpServer is too complicated to understand because it only starts the server if it's not already running. ...
48
votes
5answers
13k views

Is “convention over configuration” not violating basic programming principles?

I was looking at the WPF MVVM framework Caliburn.Micro and read that a lot of standard things are based on naming conventions. For example, automatic binding of properties in the View to properties ...
43
votes
11answers
7k views

Are error variables an anti-pattern or good design?

In order to handle several possible errors that shouldn't halt execution, I have an error variable that clients can check and use to throw exceptions. Is this an Anti-Pattern? Is there a better way to ...
35
votes
6answers
35k views

What is the best way to initialize a child's reference to its parent?

I'm developing an object model that has lots of different parent/child classes. Each child object has a reference to its parent object. I can think of (and have tried) several ways to initialize the ...
34
votes
4answers
49k views

Should angularjs directive directly interact with services or is it considered an anti-pattern?

Which one is considered better: having a directive that interacts with services directly or having a directive that exposes certain hooks to which controller may bind behaviour (involving services)?...
33
votes
5answers
63k views

Is it a good practice to create a ClassCollection of another Class?

Lets says I have a Carclass: public class Car { public string Engine { get; set; } public string Seat { get; set; } public string Tires { get; set; } } Lets say we're making a system ...
29
votes
6answers
7k views

Should I place functions that are only used in one other function, within that function?

Specifically, I'm writing in JavaScript. Let's say my primary function is Function A. If Function A makes several calls to Function B, but Function B is not used anywhere else, then should I just ...
29
votes
3answers
19k views

How to represent (enum) types in a public API

I am working on a simple API that I want to use for my own client, and to open to the public in the future. I have "Item" objects which can have different "types". The type is a C "typedef enum", for ...
28
votes
12answers
16k views

What design patterns are the worst or most narrowly defined? [closed]

For every programming project, managers with past programming experience try to shine when they recommend some design patterns for your project. I like design patterns when they make sense or if you ...
27
votes
1answer
7k views

How to choose between using a Domain Event, or letting the application layer orchestrate everything

I'm setting my first steps into domain driven design, bought the blue book and all, and I find myself seeing three ways to implement a certain solution. For the record: I'm not using CQRS or Event ...
21
votes
4answers
9k views

What is the name for the idiom using method chaining to build an object?

I frequently use a pattern where I using method chaining to setup an object, similar to a Builder or Prototype pattern, but not creating new objects with each method call, instead modifying the ...
20
votes
6answers
6k views

Advantages and disadvantages of using bit masks in database

Not so long ago I talked to my colleague and he was definitely against using bit masks because it is hard to understand all the values that are stored in the database. In my opinion it is not always a ...
20
votes
4answers
3k views

What are the practices you follow to avoid wrong data updates in big databases?

A typical advice before any production deployments is backup the DB first. This way, if the new update has some issue that can lead to potential data loss or logical data corruption, then you still ...
19
votes
9answers
1k views

What to do as a new team lead on a project with maintainability problems?

I have just been put in charge of a code project with maintainability problems. What things can I do to get the project on a stable footing? I find myself in a place where we are working with a very ...
19
votes
2answers
3k views

Is using the new System.Tuple class bad design?

I like the concept of System.Tuple in that it allows me to return multiple parameters in a single function call without instantiating a new class, however does this defy any good programming practices ...
17
votes
4answers
10k views

What is “lambda” code?

I have recently heard people talk about code being "lambda". I have never heard of this phrase before. What does it mean?
17
votes
4answers
6k views

Is it bad practice to allow user defined fields?

Generally speaking, is it considered bad practice to allow for user created fields in a database for a webapp? For example, I am making a home inventory webapp for my wife, and she is going to want ...
16
votes
5answers
2k views

Combining getters and setters

JavaScript libraries such as jQuery, combine 'getters' and 'setters' in the programming interface for example: $('element').css({'color','blue'}); will set the color or $('element').css(); will ...
15
votes
6answers
6k views

Advantages of Strategy Pattern

Why is it beneficial to use the strategy pattern if you can just write your code in if/then cases? For example: I have a TaxPayer class, and one of its methods calculates the taxes using different ...
14
votes
12answers
3k views

Is this use of conditionals an anti-pattern?

I've seen this a lot in our legacy system at work - functions that go something like this: bool todo = false; if(cond1) { ... // lots of code here if(cond2) todo = true; ... // some other ...
14
votes
4answers
4k views

Should injecting dependencies be done in the ctor or per method?

Consider: public class CtorInjectionExample { public CtorInjectionExample(ISomeRepository SomeRepositoryIn, IOtherRepository OtherRepositoryIn) { this._someRepository = ...
13
votes
6answers
7k views

Try/Catch/Log/Rethrow - Is Anti Pattern?

I can see several post where importance of handling exception at central location or at process boundary been emphasized as a good practice rather than littering every code block around try/catch. I ...
12
votes
6answers
12k views

Which order to define getters and setters in? [closed]

Is there a best practice for the order to define getters and setters in? There seems to be two practices: getter/setter pairs first getters, then setters (or the other way around) To illuminate the ...
12
votes
5answers
4k views

How to migrate my thinking from C++ to C#

I am an experienced C++ developer, I know the language in great details and have used some of its specific features intensively. Also, I know principles of OOD and design patterns. I am now learning C#...
11
votes
5answers
16k views

Database connection - should they be passed as parameter?

We have a system whereby the database connection is get once using a common method, and being pass throughout the relevant class to be used. There are doubts that passing the database connection as a ...
11
votes
3answers
5k views

When is Efferent / Afferent coupling good or bad

I have a software patterns exam this week and one of the topics we are to study is Efferent and Afferent coupling. I understand a package has a high Ce (efferent coupling) if it depends on a number ...
10
votes
2answers
8k views

Should a RESTful API be able to return files, or just a location

This has been puzzling me for a while. For example, we have a REST API that provides basic content to a system, consuming and producing JSON. At this endpoint it produces a URL to a picture and a ...
10
votes
4answers
3k views

Should every class I write adhere to an interface?

I'm writing a game in Typescript, and decided going in that I was going to try to adhere to the idea of "interface based programming", where you write code based on an interface, instead of the ...
10
votes
2answers
6k views

TDD with repository pattern

In my new project, I decided to try with TDD. And in very beginning I encountered a problem. First thing that I want to do in my application is to give ability to read data from data source. For this ...
10
votes
1answer
2k views

Avoid dependency version conflicts?

Any Java project that uses my jar, will almost certainly have an additional dependency on another jar, which my jar also contains as a dependancy. Problem is, that other jar has multiple versions. ...
10
votes
4answers
3k views

Reducing boilerplate in class that implements interfaces through composition

I have a class: A that is a composite of a number of smaller classes, B, Cand D. B, C, and D implement interfaces IB, IC, and ID respectively. Since A supports all the functionality of B, C and D, A ...
10
votes
5answers
6k views

Designing a robust architecture for multiple export types?

I'm looking for patterns or architectural guidance for an upcoming feature I'm designing. Basically, it's an export feature with multiple export targets, and I'm looking to find a way to make it ...
9
votes
2answers
7k views

Which is a better pattern (coding style) for validating arguments - hurdle (barrier) or fence? [duplicate]

I don't know if there are any accepted names for these patterns (or anti-patterns), but I like to call them what I call them here. Actually, that would be Question 1: What are accepted names for these ...
9
votes
8answers
1k views

Designs and practices to guard against erroneous null entries from database

One part of my program fetches data from many tables and columns in my database for processing. Some of the columns might be null, but in the current processing context that is an error. This should "...
9
votes
8answers
712 views

When does 'optimizing code' == 'structuring data'?

A recent article by ycombinator lists a comment with principles of a great programmer. #7. Good programmer: I optimize code. Better programmer: I structure data. Best programmer: What's the ...
8
votes
7answers
9k views

Why unused variables is such an issue?

I was cleaning unused variables warnings one day, and I started to ponder, what exactly is the problem about them? In fact, some of them even help in debugging (e.g. inspect exception details, or ...
8
votes
7answers
903 views

Is it appropriate for a class to only be a collection of information with no logic?

Say I have a class Person that has instance variables age, weight, and height, and another class Fruit that has instance variables sugarContent and texture. The Person class has no methods save ...
8
votes
4answers
384 views

Should detected vulnerabilities in old commits be remedied?

One of my projects on GitHub has received a vulnerability alert, in this case of moderate severity. The vulnerability has been detected in a dependency of an old version of the code. Current versions ...
8
votes
4answers
826 views

Is there a Haskell idiom for trying several functions and stop as soon as one succeeds?

In Haskell, I can use the type a -> Maybe b to model a function that either returns a value of type b, or returns nothing (it fails). If I have types a1, ..., a(n+1) and functions f1, ..., fn, ...
8
votes
2answers
2k views

Returning an IQueryable from an IRepository

Using the Repository pattern, is it proper to return an IQueryable of a data set (table), for generic usage? It is very handy in many cases, especially when using external libraries that leverage ...
8
votes
2answers
5k views

Storing and maintaining serialized objects in C#

What are the best practices to store and maintain serialized objects in C#? Any strategies or patterns that apply? What I have come to believe so far is this: Prefer Json over XML, both for space ...
8
votes
6answers
1k views

What are best practices when switching between projects/coming back to projects frequently?

The nature of my job is that I have to switch back and forth between projects every few weeks. I find that one of the biggest impediments to my productivity is the ramp-up time to getting all the ...
8
votes
2answers
3k views

Is implementing an interface defined in a subpackage an anti-pattern?

Let's say I have the following: package me.my.pkg; public interface Something { /* ... couple of methods go here ... */ } and: package me.my; import me.my.pkg.Something; public class SomeClass ...
8
votes
2answers
297 views

Low coupling processing big quantities of data

Usually I achieve low coupling by creating classes that exchange lists, sets, and maps between them. Now I am developing a Java batch application and I can't put all the data inside a data structure ...