Questions tagged [software-design]
Software design is the activity of deciding what properties, elements, responsibilities, interfaces, relationships and interactions are required in order to create an effective piece of software.
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Difference Between Cohesion and Coupling
What is the difference between cohesion and coupling?
How can coupling and cohesion lead to either good or poor software design?
What are some examples that outline the difference between the two, ...
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What is a software framework? [closed]
Can someone please explain me what a software framework is? Why do we need a framework? What does a framework do to make programming easier?
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What does "program to interfaces, not implementations" mean?
One stumbles upon this phrase when reading about design patterns.
But I don't understand it, could someone explain this for me?
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When to use the Bridge pattern and how is it different from the Adapter pattern?
Has anyone ever used the Bridge pattern in a real world application? If so, how did you use it? Is it me, or is it just the Adapter pattern with a little dependency injection thrown into the mix? Does ...
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Are utility classes evil? [closed]
I saw this question: If a "Utilities" class is evil, where do I put my generic code?
And I thought, why are utility classes evil?
Let’s say I have a domain model that is dozens of classes ...
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What is the benefit of using Fragments in Android, rather than Views?
When developing for Android, you can set your target (or minimum) sdk to 4 (API 1.6) and add the android compatibility package (v4) to add support for Fragments. Yesterday I did this and successfully ...
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adapter-Any real example of Adapter Pattern [closed]
I want to demonstrate use of Adapter Pattern to my team. I've read many books and articles online. Everyone is citing an example which are useful to understand the concept (Shape, Memory Card, ...
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What are the DAO, DTO and Service layers in Spring Framework?
I am writing RESTful services using spring and hibernate. I read many resource in internet, but they did not clarify my doubts. Please explain me in details what are DAO, DTO and Service layers in ...
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Coupling and cohesion
I'm trying to boil down the concepts of coupling and cohesion to a concise definition. Can someone give me a short and understandable explanation (shorter than the definitions on Wikipedia here and ...
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Is it the best practice to extract an interface for every class?
I have seen code where every class has an interface that it implements.
Sometimes there is no common interface for them all.
They are just there and they are used instead of concrete objects.
They ...
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what is the difference between a view model and a data transfer object?
I'm basing this question on Fowler PoEAA. Given your familiarity with this text, aren't the ViewModels used in ASP.NET MVC the same as DTOs? Why or why not? Thank you.
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Avoiding Circular Dependencies of header files [duplicate]
Do you have any good advice on how to avoid circular dependencies of header files, please?
Of course, from the beginning, I try to design the project as transparent as possible. However, as more and ...
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Onion architecture compared to hexagonal
Is there any difference between them (onion | hexagonal), from my understanding they are just the same, they focus upon the domain which is at the core of the application and should be technology / ...
user9124444
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Encapsulation vs Data Hiding - Java
Interviewer: What is encapsulation and how do you achieve it in Java?
Me: Encapsulation is a mechanism to hide information from the client. The information may be data or implementation or ...
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Find Number of CPUs and Cores per CPU using Command Prompt
I am trying to retrieve the Number of CPUs and Cores per CPU using Command Prompt.
I have executed the following command:
wmic cpu get NumberOfCores, NumberOfLogicalProcessors/Format:List
I get this ...
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Decompose microservices: Business capability vs Domain
As I read, there are two patterns to define one microservice, by business capability and by subdomain. But I still find it very ambiguous. I get confused how these two patterns differentiate from each ...
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Repository and Data Mapper pattern
After a lots of read about Repository and Data Mapper I decided to implement those patterns in a test project. Since I'm new to these I'd like to get your views about how did I implement those in a ...
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What PHP application design/design patterns do you use?
Please share your favorite application design / design patterns for use in PHP with me. Some things I'd like to know:
How your folders are designed
How you use object oritentation in your PHP ...
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Questions about VIPER - Clean Architecture
I've been reading about Clean Architecture from Robert Martin and more specifically about VIPER.
Then I ran into this article/post Brigade’s Experience Using an MVC Alternative which describes pretty ...
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What is the core difference of redux & reflux in using react based application?
Recently I conducted a preliminary study on developing an E-commerce site and discovered that redux and reflux both come from flux architecture in Facebook and that both are popular. I am confused ...
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Adapter Pattern: Class Adapter vs Object Adapter
I have a few questions about the Adapter pattern. I understand that the class adapter inherits from the adaptee while the object adapter has the adaptee as an object rather than inheriting from it.
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the significance of java RMI please? [closed]
Why do people use RMI, or when should I use RMI? I read those tutorials about RMI on oracle's website. But it doesn't provide enough practical examples.
To my understanding, software should have its ...
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Why encapsulation is an important feature of OOP languages? [closed]
I came across different interview where question was asked to me why encapsulation is used? Whose requirement actually is encapsulation? Is it for users of program? Or is it for co-workers? Or is it ...
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Should I throw on null parameters in private/internal methods?
I'm writing a library that has several public classes and methods, as well as several private or internal classes and methods that the library itself uses.
In the public methods I have a null check ...
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How to design an application in a modular way?
I am looking for pointers, suggestions, links, warnings, ideas and even anecdotical accounts about "how to design an application in a modular way". I am going to use python for this project, but ...
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Should I share models across multiple microservices?
I'm in the analysis phase of a big project, that will be created with a micro services architecture. I am pretty confident that (at least for the next 3 years to come) the whole codebase will be ...
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Why doesn't JavaScript get its own thread in common browsers?
Not enough that JavaScript isn't multithreaded, apparently JavaScript doesn't even get its own but shares a thread with a load of other stuff. Even in most modern browsers JavaScript is typically in ...
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How do I choose heap allocation vs. stack allocation in C++?
One of the C++ features that sets it apart from other languages is the ability to allocate complex objects as member variables or local variables instead of always having to allocate them with new. ...
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How to understand the VIPER clean architecture?
I recently discovered VIPER clean architecture and I started looking for sample tutorials on applying this architecture on the Android platform. However, what I only found was sample projects which ...
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Keeping track of utility classes
I've recently been more and more frustrated with a problem I see emerging in my projects code-base.
I'm working on a large scale java project that has >1M lines of code. The interfaces and class ...
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Django - how to visualize signals and save overrides?
As a project grows, so do dependencies and event chains, especially in overridden save() methods and post_save and pre_save signals.
Example:
An overridden A.save creates two related objects to A - ...
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Clean Architecture - Robert Martin - How to connect use cases
I'm trying to implement the Clean Architecture described by Robert Martin.
More specifically I'm using VIPER which is an iOS version of Clean Architecture.
The problem I have is as follows:
The user ...
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How to persist objects which implement the State pattern?
I am new to the State design pattern and I can't find a proper example of saving different states of an object to the database (SQL Server in my case). The scenario is quite similar [almost identical] ...
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python: abstract base class' __init__(): initializion or validation? [closed]
class ABC is an "abstract base class". class X is its subclass.
There's some work that needs to be done in any subclass of ABC, which is easy to forget or do incorrectly. I'd like ABC.__init__() to ...
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Constructors, templates and non-type parameters
I've a class that must depend for some reasons from an int template parameter.
For the same reasons, that parameter cannot be part of the parameter list for the class, instead it is part of the ...
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How to build a class structure, when members are also structured hierarchically?
I'm building a PHP web application, that should provide to the user a possiblity to order an "installation"/setup of a (ConnectDirect or File Transfer Gateway) connection between him and another ...
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Design principles for complete noobs? [closed]
I've been programming for around a year now, and all the stuff that I've written works - it's just extremely poorly written from my point of view. I'd like to know if there are any (free) good books ...
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Delegates as Properties: Bad Idea?
Consider the following control (snipped for brevity):
public partial class ConfigurationManagerControl : UserControl
{
public Func<string, bool> CanEdit { get; set;}
public Func<...
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file name vs file object as a function argument
If a function takes as an input the name of a text file, I can refactor it to instead take a file object (I call it "stream"; is there a better word?). The advantages are obvious - a function that ...
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When to call the gang of four? [When to use design patterns?]
In The Guerilla Guide to Interviewing Joel says that guys who want to get things done, but are not smart will do stupid things like using a visitor design pattern where a simple array would be ...
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How To Make a Tetris Clone?
I am working on coding a Tetris clone in XNA C# and am unsure of the best way to approach the data structure side of the game on a high level.
I am totally fine with the collision detection, ...
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Is it a bad practice to use jQuery in Angular? [closed]
My question is the following. Should I avoid using any kind of jQuery code in Angular application as it seems legit to have only one thing interacting with DOM.
Another question is if anyone came ...
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Twitter-like app using MongoDB
I'm making an app that uses the classic "follow" mechanism (the one used by Twitter and a lot of other apps around the web). I'm using MongoDB.
My system has a difference, though: an user can follow ...
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Is Event sourcing using Database CDC considered good architecture?
When we talk about sourcing events, we have a simple dual write architecture where we can write to database and then write the events to a queue like Kafka. Other downstream systems can read those ...
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Purpose of Utility tree in ATAM
What is an utility tree and what is it's purpose in case of Architecture tradeoff analysis method(ATAM)?
Thanks
user1323981
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DDD: guidance on updating multiple properties of entities
So, i decided to learn DDD as it seems to solve some architectural problems i have been facing. While there are lots of videos and sample blogs, i have not encountered one that guides me to solve the ...
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DDD navigation to entities inside aggregate root via composite identity
I have an aggregate root Products which contains a list of entities Selection, which in turn contains a list of entities called Features.
The aggregate root Product has an identity of just name
The ...
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Marker interface vs empty abstract class
I am facing difficulties to decide between using a marker interface or an empty abstract class.
I have two classes BrokerResponse and Notification, which have no structural similarity. The only thing ...
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How to catch DB errors and translate them into meaningful information for the business layer?
Usually I have to insert some data in a DB and it can't be inserted because the table has constraints preventing me from doing that. With the app I'm developing, some business rules (like "there are ...
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DTO Design in TypeScript/Angular2
I'm currently developing an Angular 2 application. While developing I started to use TypeScript classes to create objects from JSON I receive through HTTP or when creating a new object in a form.
The ...
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