A design pattern is a general reusable solution to a commonly occurring problem in software design.

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Is Functional Programming a viable alternative to dependency injection patterns?

I have recently been reading a book entitled Functional Programming in C# and it occurs to me that the immutable and stateless nature of functional programming accomplishes similar outcomes to ...
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2answers
115 views

Client-Server Application Object with child Objects

Actually I'm going to build an Client Server Application, at the Login I recive the User Object from the Server. An user has a List of tasks, but I don't want to load them at the Login. So what would ...
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3answers
545 views

When do programmers use code first approach?

This is just not related to asp.net mvc but rather related all the mvc frameworks that support code first approach. One of the advantages I often see on asp.net mvc and tutorial blogs is that it ...
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1answer
140 views

Where should the following business logic be written?

I have a C# console application. This application has many different projects/C# class files, each of them dedicated to parsing a certain kind of XML and creating an object, called 'Response'. Now, ...
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4answers
969 views

Is the Single Responsibility Principle applicable to functions?

According to Robert C. Martin, the SRP states that: There should never be more than one reason for a class to change. However, in his book Clean Code, chapter 3: Functions, he shows the ...
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1answer
211 views

Program to look at the first say 5 characters of a word and return a string if that string is actually the first 5 characters of a word?

For example, say I have a string and it has the letters: RDNAL This is not an actual English word or it doesn't start an actual english word, so the program would skip this string and would avoid ...
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2answers
182 views

Implementing an anti-corruption layer with domain logic

I'm building an application that compiles a single PDF document from multiple source PDF documents as follows: it takes the first page of each source document, stamps certain information on top of ...
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2answers
83 views

Class design and object references

Here is a very basic example of what I am trying to do. In reallity there are more relations but not something extreme or memory heavy. public class ClassA : ISomething { public double property ...
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5answers
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If Else - Repeated Code Logic

My boss gave me a project with a particular logic. I have to develop a web page which has to lead the navigator through many cases until he/she arrives at the product. This is the path scheme of the ...
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2answers
139 views

Definition of the NHibernate Mapping by Code / EF Code First pattern?

Sub-questions: Does this pattern have a formal definition? Who invented it? Is it considered a DSL? The reason why I am asking is because I would like to better assess its applicability to ...
3
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1answer
143 views

Do you still need created_by and updated_by attributes with dedicated auditing?

For as long as I have been writing database-backed websites, I have included created_by, created_at, updated_by, and updated_at in every single table. As you can guess, whenever a record gets created ...
2
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2answers
97 views

Delegating work and programming to component interfaces

I have a MessageHandler class which receives and validates messages before determining which components in the architecture they should be delegated to so they can be processed. This involves calling ...
8
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2answers
1k views

Is using interfaces for datatypes an anti-pattern?

Suppose I have a various entities in my model (using EF), say User, Product, Invoice and Order. I am writing a user control that can can print the summaries of entity objects in my application where ...
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0answers
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Hierarchical ViewModels and tracking IsDirty/PropertyChanged events

I have a set of ViewModels depicted like in the below picture. And, I have a couple of commands AcceptCommand, CancelCommand in the Top Level View Model that are bound to Apply, Cancel buttons ...
3
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1answer
248 views

Nested REST urls and parent id, which is better design?

Okay, we have two resources: Album and Song. Here is API: GET,POST /albums GET,POST /albums/:albumId GET,POST /albums/:albumId/songs GET,POST /albums/:albumId/songs/:songId We know that we hate ...
6
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2answers
228 views

Why does 'zip' ignore the dangling tail of the collection?

C#, Scala, Haskell, Lisp and Python have the same zip behaviour: if one collection is longer, the tail is silently ignored. It could be an exception thrown as well, but I didn't heard of any language ...
2
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1answer
94 views

Is Current CoffeeScript Module Pattern Valid?

I have a Node.js web application that's written in CoffeeScript, which has a set of "services". These various services are currently exposed as a CoffeeScript class, which does a few things that I ...
4
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4answers
641 views

What architecture/design to adopt when consuming a RESTful API? (iOS App)

TL;DR Part 1) I want to refactor the biggest part of the app on which I work - and it is pretty much spaghetti. It's a single class that makes the requests to the server, parses the JSON and saves ...
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1answer
115 views

How to name a function that makes sure an element exists and returns it?

function getOrInsertEmptyElemById(id){ var elem = $(id) || document.body.insert('<div id="'+id+'"></div>'); return elem; } I find myself using functions like the above quite ...
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1answer
53 views

Methods accounting for all input to method

This is more of a conceptual question. Let's say that you had the following enum public enum FooEnum { ALPHA, BETA, GAMMA, DELTA; } And let's say you have the following method: ...
2
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0answers
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What design pattern is used in this delegating scenario?

I am currently having to bend some framework API to fit my usecase. The framework provides generic interfaces such as public interface Processor<T> { T process(T t); } with various ...
1
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3answers
76 views

Design of actions handlers requiring some order

I have a REST application where 'actions' can be executed to perform anything in the system. For example: user.save, user.get, etc... I also have pre and post execution 'handlers'. For example a ...
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2answers
412 views

What kind of programming pattern is appropriate for programming an algorithm with rules and exceptions?

I'm interested in coming up with an algorithm to solve a guessing game. The player is attempting to guess a sequence of 4 unique numbers from 1 to 9. After a guess, they are told how many numbers of ...
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3answers
177 views

How to design a solution that needs dynamism using Inheritance [closed]

I have below code/classes/interfaces: An Interface: public interface Animal<A extends Animal<A>>{ void fight(A otherAnimal); } 2.Tiger class which is implementing Animal ...
0
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4answers
289 views

2 methods that are 75% the same? [closed]

I have code that violates the DRY principle and I would like to consolidate 2 methods as much as I can, but the problem I am facing is that they have some differences, I would say they are about 75% ...
37
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11answers
4k views

Constructor-only subclasses: Is this an anti-pattern?

I was having a discussion with a co-worker, and we ended up having conflicting intuitions about the purpose of subclassing. My intuition is that if a primary function of a subclass is to express a ...
2
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1answer
224 views

Reducing the complexity of over-designed code

I have just started working at a company where I have inherited a C# codebase from a previous developer. I know programming well, have an engineering degree + an (unfinished, several year long) PhD ...
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2answers
333 views

Sharing code logic between controllers, through the Model layer?

As I originally conceived my Model layer, it was only supposed to hold data and no code. I receive DTOs from web-services, they are mapped into my Model objects. Those model objects usually end up ...
2
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2answers
228 views

Problems with OO design for application with pluggable components

I'm trying to refactor an ugly code and make it easly extendable in the future. The application should be nothing else but a series of components that have input(s) and output(s). The components ...
2
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2answers
139 views

Is there a name for a dictionary that returns the key as the value by default? [closed]

A dictionary that returns the key as the value by default can be used in cases where exceptions or translation is needed. E.g. One could do i18n = SpecialDict() if spanish: i18n["Hello"] = ...
3
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2answers
209 views

Scheme/Design Pattern for allowing a certain outside class to set properties

I came up with a solution (in PHP) to a problem and am wondering if it is a named Design Pattern, and if it is good practice. I have a collection class and an item class. The collection class is the ...
2
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1answer
210 views

What is SteppedPattern?

I read this article on Jon Skeet's blog where he delves into the topic of performance on object pooling & thread safety. In the article he makes a reference to SteppedPattern: Most of our ...
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2answers
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What is the better way of getting different outputs for two very simmilar related workflows

I have a very concrete scenario but I think it would be quite frequent. I'm trying to come up with a solution that it's "better" by better meaning more scalable, reusable and not smelly. I'm working ...
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2answers
89 views

Design Pattern for Removing Default Listeners

We have a standard GUI control with a bunch of default listeners like that: class OurControl extends Control { OurControl() { addMouseWheelListener(new DefaultMouseWheelListener()); ...
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1answer
176 views

Consuming a rest API that exposes nested objects

I have a series of nested objects, exposed over a REST API, like so: class Categories { int id; string name; List<Subcategories> subcategories; } class Subcategories { ...
0
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1answer
154 views

Better pattern than large if/else if/else for checking conditionals [duplicate]

I've got a fairly large set of booleans I'm checking in javascript, and then using them to alter the state of a layout in my React app. The whole thing is unwieldy, difficult to read, inelegant, and ...
0
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1answer
97 views

Pattern for separating UI code from logic in Wicket

I'm using Apache Wicket for developing web apps, I have developed a few for the last year and it has been great; today I was looking at a few pages and most of them look like this: public class ...
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0answers
32 views

Strategies for maintaining backwards compatibility when persisting objects to XML [duplicate]

I am using XStream to persist Java objects to files. This works fine and so far I have had no problems. However, in the course of development, the objects have changed. Some new properties have been ...
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0answers
142 views

Choosing the right design pattern/architecture for a scenario

I have a situation, in which I would like your opinion about the best approach that I should take. Let's consider 10 classes (obj001, obj002 etc.) all which represent some business entities, and are ...
0
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1answer
135 views

Why use the Singleton pattern over class functions and fields? [duplicate]

I'm going to start by saying that I understand that programming in mostly class functions and variables can be harmful to object-orientation, and that most of the time an instance is preferred. I'll ...
2
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0answers
70 views

Injecting data processing logic into class

I want find more elegant and appreciate way to inject processors into CommandProcessorDispatcher class. Or it can be another one solution (the goal is separate each command processing logic to ...
16
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1answer
745 views

When to use prototypical programming in JavaScript

I've spent a good bit of time developing simple widgets for projects in the following way: var project = project || {}; (function() { project.elements = { prop1: val1, prop2: val2 } ...
1
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2answers
463 views

Which design (pattern) would be suitable to abstract logging platforms?

I need to create a simple system to abstract logging platforms. The idea is that I'd like to be able to exchange or activate a logging platform (nlog, log4net, enterprise library) via some ...
0
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1answer
173 views

Possible way to make java class builder more abstract by using interface required keys

I'm looking for a more abstract pattern for builders that handles required fields without the need of writing a validator that checks if all requried fields are set. I like this builder. But is ...
0
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1answer
181 views

Is this a good service locator, and is this service locator pattern(?) OK?

I'm working in Zend framework 1 and was using Zend_Registry to store objects so that I could replace them in my controllers while unit testing: $auth = Zend_Registry::get('Auth'); // set in ...
0
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2answers
258 views

Design pattern for multiple companies in AngularJS

We are on the verge of launching v3 of our in-house product. v2 was written completely in AngularJS and V3 will be the same, but written completely in Typescript. We have a few customers that have ...
1
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1answer
385 views

mySQL / PHP design pattern - one function multiple queries

So here's the gist of it. I'm looking for a design pattern where I can have one function, say queryHandler that gets the query and the parameters from a number of different functions and returns the ...
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1answer
219 views

Should I use Strategy Pattern for this task?

I'm setting up a data validator that will iterate through the rows of a spreadsheet, and for each column, perform a validation check. I was thinking that this might be an appropriate task for the ...
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1answer
102 views

Should factory make context or concrete strategies objects in strategy-factory pattern?

In a typical strategy pattern class Strategy { public: virtual int execute() const = 0; } class StrategyA : public Strategy { public: int execute() const override; } class StrategyB : ...
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1answer
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Design pattern where decorated object may ask for things like “status updates” from the decorator to perform it's role?

Here's an situation that has haunted one of my open-source projects for quite some time. Imagine if you could represent every front-end input form with a single backend object? An object that ...