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

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Build a map with city blocks and road

Is there a design pattern or well known algorithm to build a simple map with roads and city blocks? To have an idea of what's my target i describe some of the constraints and the context: a matrix ...
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4answers
200 views

How to ensure objects unique by equality?

I frequently have this problem but didn't find it as an established programming pattern. I have some Class C whose equality is determined by some key k and I want to prevent time-consuming ...
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1answer
75 views

How to deal with product owner who refuses to follow UI design rules

We develop Android application. We base on old version of similar application developed in our company. This old application was designed by some noobs which didn't follow UI Android design rules. ...
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Web Developer interview questions

I read an article today that listed some basic questions about web development: Describe how POST data was submitted to a server by a browser. Explain a number of HTTP status codes (except maybe 404 ...
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4answers
573 views

Proper Model-View-_____ design

I've been reading up about Model View Controller, Model View Presenter, Model View ViewModel, and so on, and generally, the underlying concept seems pretty simple to understand: keep the pretty ...
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1answer
127 views

How does the consumer-producer solution work?

I'm only a beginner, and my book doesn't cover this subject. I have researched my problem and found that an implementation of the consumer-producer pattern is the ideal solution, and have Googled it, ...
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1answer
203 views

What is this pattern called? Run finally?

Is there a name for this pattern? I've written this kind of thing a few times in JavaScript and recently found myself writing it in C#. Thing is, I expect this has already been implemented in a ...
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2answers
171 views

API - How to handle scope based functionality?

TLDR; Where and possibly how should I implement scope based logic in the example code? I have got a ASP.NET Web Api. The Api uses OData (on top off REST) for data endpoints and OAuth 2.0 ...
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Name/Fix for Production Code Whose Sole Purpose is to Facilitate Testing? [duplicate]

The linked "duplicate" question is an iffy match at best, because it's asking is pattern X OK (YES/NO) and I'm clearly already in the NO camp, and subsequently asking what is pattern X called ...
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1answer
128 views

The ViewController design in iOS vs MVC in tradiational web apps design

As I came from the background of webapps and move to iOS programming, I am wondering why we can't just apply the MVC design approach to native apps, i.e. in iOS, the view and controller are tightly ...
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1answer
137 views

Methods for structuring JavaScript SDKs

I've built a REST API and have been using Backbone models throughout a couple different applications to communicate to it. I would really like to build a single JS SDK that can be used in any ...
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4answers
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Why do code-bases in n-tier development have an equal amount of, if not more, JavaScript code now?

I've been doing web programming for a long time now, and somewhere, I lost track of why we are doing what we are doing today (or how did we come to do things this way)? I started out with basic ASP ...
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1answer
42 views

Patterns for subclass constructors that vary the parent class constructor slightly

So, my problem is in the context of an MVC-style approach. The code here is PHP, but I'm hoping this is a design issue independent of it. abstract class Controller { private $domain; private ...
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1answer
71 views

Designing a better performing total permissions setup for multiple permission levels

We've got a global system that we are attempting to solve a permissions issue around. Currently, our system serves a number of different applications out to our clients and each client has their own ...
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2answers
218 views

How to design a scriptable communication emulator?

Requirement: We need a tool that simulates a hardware device that communicates via RS232 or TCP/IP to allow us to test our main application which will communicate with the device. Current flow: ...
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6answers
705 views

What should an object be called that contains only setters and getters? [on hold]

Suppose there's an object that contains only setters and getters: class Config { public void setName(String name) { this.name = name; } public String getName() { ...
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1answer
364 views

State Pattern - should a state know about its context?

I am referring to the state pattern as described in this link. In the example class diagram, a context has numerous states. However, it does not show how does a state communicates with a context ...
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3answers
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Communicating between unrelated components/objects

Imagine that I have a game, with Monsters, Missions, Vehicles, and of course their controllers and such, so a Monster class, Mission Controller class, Vehicle Controller class and so on. Suppose that ...
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How accurate is “Business logic should be in a service, not in a model”?

Situation Earlier this evening I gave an answer to a question on StackOverflow. The question: Editing of an existing object should be done in repository layer or in service? For example ...
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1answer
58 views

Using entityManager/repository Class/session factory directly in controller

I wonder what is your approach on following subject: let's say we have MVC structure with entities, repositories, controllers and service layer. My approach to use above was pretty clear for me: ...
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3answers
226 views

Best approach for tracking dependent state

Let's pretend I work on a project tracking application. The application is a database backed, server hosted, web application. In this application there are Projects which have many Activities which ...
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1answer
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Useful design patterns for working with FragmentManager on Android

When working with fragments, I have been using a class composed of static methods that define actions on fragments. For any given project, I might have a class called FragmentActions, which contains ...
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0answers
58 views

Need to refactor file downloader and post processing utility [duplicate]

Not sure whether this is the right forum to ask this but here goes. Using this solution - http://stackoverflow.com/questions/26571351/replacing-if-else-logic-with-state-strategy-pattern I was able to ...
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6answers
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What is the simplest human readable configuration file format? [closed]

Current configuration file is as follows: mainwindow.title = 'test' mainwindow.position.x = 100 mainwindow.position.y = 200 mainwindow.button.label = 'apply' mainwindow.button.size.x = 100 ...
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1answer
134 views

Where and how to reference composite MVP components?

I am learning about the MVP (Model-View-Presenter) Passive View flavour of MVC. I intend to expose events from view interfaces rather than using the observer pattern to remove explicit coupling with ...
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57 views

MVVM dilemma - keep it simple, stupid VS it breaks MVVM! [closed]

The MVVM pattern taken as a whole can be quite complicated. Sometimes it appears that there is more work involved following the "best practices" than it's worth. How can you tell when to adhere to the ...
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2answers
240 views

Does this Decorator implementation violate the Liskov Substitution Principle?

Please consider the following implementation of the Decorator design pattern: WordBank objects store strings and return them to the client through the method getWords(). The decorator class, ...
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1answer
145 views

Should we use data object (or the data transfer object) for sharing data between these three classes?

I found an article by Martin Fowler that has made me doubt my design choices, particularly about data objects. Martin Fowler has written an article about what he thinks is a code smell. In this ...
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1answer
166 views

Null Object Pattern and Input validation - copy real implementation or silently accept everything?

I have a WifiComponent in my Camera in my client application. It's responsible for handling the Wifi-related functionality of the Camera. The Camera represents a real world camera. This WifiComponent ...
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1answer
47 views

Control (avoid) changing fields with side-effects

I have been thinking about a design problem and possible solutions in my own. I am pretty sure I am not the first one to have noticed it, but I cannot google for it since I do not know the standard ...
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8answers
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When writing object-oriented code, should I always be following a design pattern?

Is there a conceivable design pattern for any object-oriented program? I ask this because recently I saw an implementation of a Door class with a Lock. It was part of a test and the answer said that ...
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1answer
169 views

When to use packages or Repositories in Laravel?

I'm a Laravel (PHP) developer, and new with DI, Packages (workbench) and Repositories (Pattern). I want to know about the best concept/methodology for a more flexible design; ie. the project can grow ...
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53 views

Generalization of phase based systems for card and board games

In an exercise of futility I'm trying to abstract and generalize a framework where to build any turn/rule based system. I've had a head start but after decompiling HearthStone I'm second-guessing that ...
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18answers
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How can one manage thousands of IF…THEN…ELSE rules?

I am considering building an application, which, at its core, would consist of thousands of if...then...else statements. The purpose of the application is to be able to predict how cows move around in ...
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3answers
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Client vs Creator in Factory Method and Abstract Factory patterns

This page descibes one important difference between Factory Method and Abstract Factory: http://architects.dzone.com/articles/factory-method-vs-abstract The difference, according to this page, is ...
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1answer
326 views

Interface questions for using Command Pattern and Dependency Injection together

I have many projects that have essentially the same high level requirement: test all hardware on a device. Each device can have a different communication protocol, requires different test equipment to ...
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1answer
201 views

How do you keep control in a large software project? [duplicate]

I've a large-ish software project that I'm the sole developer for (~80KLOCS and counting - I know there are much larger projects out there, but it's an order of magnitude larger than I've ever had to ...
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1answer
132 views

Best OOP pattern to use for creating a commandline SQL API for a proprietary json based company datastore

We need to create a SQL commandline tool for querying a proprietary json based datastore. I'll be using java. Any suggestions on the primary OOP design pattern I should use for building this API? ...
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1answer
42 views

Duplicate method in spring services, how to refactor?

ServiceOne.java private void doStuff(){} ServiceTwo.java private void doStuff() Where to put common code ? Shall I create a new service, but then what interface will it implement ? Or shall I ...
52
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3answers
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What is an Anti-Corruption layer, and how is it used?

I'm trying to figure out what the Anti-Corruption layer really means. I know that it's a way to transition/work around legacy code or bad APIs. What I don't understand is how it works and what makes ...
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1answer
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How best to design a SQL Parser in java, any prevailing design pattern comes to mind? [closed]

What software pattern is most useful for building a SQL Parser? I would like some ideas on how to even get started on something like this.
3
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2answers
188 views

How and Why should class modifiers enforce or prevent inheritance and the ability to override

This isn't really related to anything I am working on currently, its more of a question I really couldn't find an answer for. Class modifiers like MustInherit or NotOverridable to me, seem like they ...
0
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1answer
167 views

Is factory pattern a right pattern for the situation described here?

Is factory pattern a right pattern when we want to consolidate the related objects? Problem - In the Set-top box, I have a user-io, basically the interface to control the settop box - The user-io can ...
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0answers
37 views

Choosing a pattern for domain logic on top of ORM model

I am using Python and ORM, particular SQLAlchmey. I have an ORM model which implements data mapper pattern. The model has a field state, which can take one of several states, let's say NEW, CANCELLED, ...
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C# structure needed for dynamic behaviour

I am using Unity to build a visualisation of a serious game. I am using the C# programming language. My problem is that I receive data from a JSON and I parse it and I end up with a list of different ...
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0answers
99 views

Program Architecture: How to manage objects that are interdependent

Consider the following case, image I making a simple chat program; I want it to be extensible such that it would be fair easy to add add different scripting and user interfaces. I want the core ...
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1answer
146 views

PHP - Repository matrix pattern?

I'm trying really hard to refactor some of my legacy code in the project using best practices and design patterns + DDD so I'd love some feedback on an issue I'm currently having. Let's assume that I ...
2
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1answer
124 views

Is the application architecture of Facebook Flux a new idea?

Facebook announced that it's using the architecture they call Flux to develop their projects. It consists of a single direction dataflow, and concepts like a Dispatcher, Stores and Actions (well ...
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2answers
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At what granularity are events recorded in Event Sourcing?

I'm growing my understanding of event sourcing. My understanding is that it provides a means of recording events as they happen so that given a common beginning state and an audit log of recorded ...
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1answer
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Communication between Multiple Presenters in MVP

I'm designing an application using the MVP pattern, but a few of the edge cases for the system rely on communication between multiple presenters. View 1 calls Presenter 1 which does Operation A ...