Questions tagged [design-patterns]
A design pattern is a general reusable solution to a commonly occurring problem in software design.
1,358
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The Abstract Factory design pattern as a Database Operations program
File - DatabaseOperations.h
This file contain classes representing database operations for three different types of databases (relational, document based and graph based) like establishing connections,...
1
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1answer
38 views
Factory Method Design Pattern Implementation as a Coffee maker program
File: InfoFactory.h contains four classes.
CaffienatedBeverage is an Abstract class with one pure virtual function Name. It ...
-1
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0answers
30 views
PHP class about acts for municipal property with many properties, getters and setters
Can someone tell me is this good practice or somekind of design pattern.
I want to avoid big class with many properties, setters and getters, and other methods.
Object properties match database table ...
2
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2answers
37 views
5
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1answer
480 views
Designing an URL Shortener
Recently I was assigned a URL shortener design problem while interviewing with a well known organization. Here is the exact problem statement:
Build a simple URL shortener service that will accept a ...
3
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2answers
137 views
Implement IDisposable correctly using object composition principle
Is it possible to implement IDisposable pattern correctly while using object composition principle to promote code-reuse, reduce code duplication and hide verbose &...
7
votes
2answers
229 views
Constructing a DSL with properties instead of functions, for use in a type-safe pseudo-builder
As one step in a larger builder setup, I need to build a small collection of objects, each with a small number of required attributes, and each of those with a small set of possible values. The actual ...
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0answers
40 views
Embedded services using chain of responsibility?
I currently have a few "worker services" that wrap existing code to automate incredibly repetitive code. A few examples are:
Method analytics.
Iteration support.
Exception logging.
My ...
4
votes
0answers
82 views
License-holder editing application
I am building a WPF (Windows Presentation Foundation) application. And I'm trying to use the MVVM (Model–View–ViewModel) design pattern. It's fascinating and rewarding, even though it seems overly ...
5
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1answer
490 views
Using a generic call to access different variations of a method
In the code below, the primary purpose of class MyRNG is to create a single method getMyRandom() that will return a random ...
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1answer
52 views
Proper way to Implement a Birthday Class in Object Oriented Python [closed]
I have the following class
...
3
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2answers
75 views
CLI-Client for interacting with daemon
I have a daemon which I am able to interact with through a cli-client. The daemon will perform some tasks in future e.g. monitoring the rate at which files are added to a directory.
Right now when I ...
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0answers
17 views
Create Many Subtypes which are all exactly the same VS use just one type
Is it good practice to create many subtypes which are all exactly the same just for more descriptive class names? I did this but then I realised all my subtypes were redundant, and it seemed kind of ...
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0answers
39 views
Replace SingletonPattern by using IOC Container based architecture
I have a legacy winForms application that now I'm in charge of maintaining and developing.
This app has a lot of singleton instance....
Some are very similar to service that wrap other component or ...
6
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0answers
67 views
Efficiently generate distinct subsets which sum to a particular value
Related: Find all distinct subsets that sum to a given number
This code is supposed to efficiently generate all subsets of a list such that the subset's values sum to a particular target value. For ...
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0answers
62 views
Filtering what strategy to use in strategy pattern [closed]
I have a situation where I've used the strategy pattern but got many different strategies that are available to the client code that needs to select the appropriate strategy, this is because there's a ...
2
votes
2answers
103 views
Parking places design
I got a question:
Design a parking system. There are 3 types of parking spaces: big, medium and small.
Implement ParkingSystem class(int big, int medium, int small)....
1
vote
1answer
75 views
Minimal list definition in Rust
As a purely pedagogical exercise, I've been trying to use Rust's (very expressive) type system to define the bare minimum one might expect from an ordinary list type.
While there's likely a higher-...
2
votes
1answer
67 views
Scrape multiple twitch IRC chats
I've always struggled to create and sustainable, organizated, clean code.
I tried to use a Factory method and it's working better now that I created another class.
I know I should write documentation,...
2
votes
1answer
67 views
Asp.Net overall design pattern integrating REST, dependency injection, and Hosted Services (See full project at Github)
I'm new to C#, and want to conform as much as possible to good design patterns. This code is the beginning of a Microservice, running as Asp.Net. It is based on a Microsoft tutorial doing similar work....
6
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2answers
183 views
Usage of Factory pattern for maintaing bookshelf having books, magazine and notes
I have tried to achieve the following task using Factory Pattern with php-7.0.
Define the classes and their methods (including parameters and return types) for a system that consist of a bookshelf,
...
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43 views
Python - Pagination class
I built a small flask app and a lot of routes do need some kind of pagination system. However, in some cases I would like to just display n-2, n-1, n, n+1, n+2 ...
2
votes
1answer
81 views
Stack Exchange Marathon Bot – Part 1: Bot structure
This code review is for my Stack Exchange Marathon Bot project, a Telegram bot for playing a dumb little game involving the Stack Exchange network. Since the codebase is not that small, in this post I ...
1
vote
1answer
59 views
How can I refactor for handling multiple proto generated service clients by eliminating double await and the DRY code?
I'm having doubts about which is the best strategy to manage the many service clients in this web app.
"Best" in terms of a good compromise between user's device RAM and Javascript execution ...
2
votes
2answers
68 views
Web scraping and design pattern lifting
I would like to get some feed back on my code; the goal is to get all agencies address of banks. I wrote a pretty simple brute force algorithm.
I was wondering if you would have any advice to improve ...
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0answers
31 views
Implementation in Azure Blob Function Trigger for Insert into Database
I have created Azure Blob Trigger function. If file is inserted in Azure Blob Container at that time this function is trigger and based on that file data we need to insert into our database table.
My ...
2
votes
1answer
93 views
Python: separation of concern User Model and User DB
I am working on a small side-project since a couple of weeks, I am using Flask but trying to use as few libraries as possible and no ORMs (for learning purposes.
I am currently working on the User ...
5
votes
1answer
145 views
Anemic class that binds functionality
I have cleanly separated functionality of a message bus - namely the diagnostics (optional), sending, decoding and the bus driver, I need to now bind this together and have done so with a ...
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2answers
80 views
Factory / Builder Design Pattern in Python
Situation: I have implemented a factory design pattern in Python as below. There are different screens which have different configurations. One can register the screen in the factory and get the ...
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0answers
41 views
Flask blueprints and context_processor - Best approch?
I am working on a Flask application (side-project) to send text-messages to customers using Twilio. There is two different list of customers, 1 for testing and for ...
4
votes
1answer
55 views
Improving Mancala Game
https://www.mastersofgames.com/rules/mancala-rules.htm
I am trying to create a working Mancala Game in scala, Currently, I have 3 classes, Board, ...
2
votes
0answers
68 views
Design a parking lot [closed]
I have tried to design the parking lot problem. Here is the problem statement.
Design a parking lot with multiple floors where customers can park
their cars. Each parking floor will have many parking ...
4
votes
2answers
83 views
Housekeeping script improvements
I have built a housekeeping script and I would like to improve it.
I have a JSON file with the details such as directory path, number of days after which the directory or file should be zipped, ...
3
votes
2answers
67 views
Python Back-end registration validation
I'm working on a personal project (Flask CRUD app) and I am currently building the user service. I am trying to use as less as libraries as possible (that's why I do not use WTF-forms for example, ...
2
votes
1answer
53 views
Python (Flask) - User registration system
I am working on a simple CRUD app as a personal project using Flask. I am currently working on the user service and I just finished the registration process. I am also trying to use as less as ...
0
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0answers
8 views
DI container class
I have created this DI container class lib to be used to in any other external project as a learning exercise.
Please review, and suggest any improvements or comments you have.
...
2
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0answers
47 views
Cron expression parser
Problem
Write a command line application or script which parses a cron string and expands each field
to show the times at which it will run.
~$ your-program "*/15 0 1,15 * 1-5 /usr/bin/find"...
2
votes
1answer
74 views
Python - Inheritance: sharing objects across instances
Use case - motivation & challenge
Hi all! I have been working with Python for the last two years, but never learned proper object-oriented programming and design patterns. I've decided for this ...
3
votes
2answers
72 views
Replace words from a file with words from a dictionary based file
I'm working on a coding challenge that tasks me with taking a file with a dictionary, reading from it, and then replacing the matching words from the input file with what is found in the dictionary.
I ...
0
votes
1answer
69 views
Calculate tax return [closed]
Please consider this code for a TaxReturnCalculator (and ignore both the suboptimal use of float instead of ...
2
votes
3answers
124 views
LRU Cache Implementation in C++
I am learning C++ by implementing small design problems. I have tried to implement LRU cache and the implementation that I have attached here works fine.
However, I am not sure whether my code is in ...
2
votes
1answer
123 views
writing a generic object pool in C++
For a hobby project, My aim is to design and implement a generic system for pooling an arbitrary class of object. I tried implementing it using templates.
This pool should support 4 actions:
"...
3
votes
1answer
197 views
Board game design in C++
I'm trying to build a board game and solve it using algorithms such as Monte Carlo Tree Search in C++. My current design follows this python project, in which I have a class hierarchy for ...
2
votes
1answer
55 views
This code loops through a GlobalEmployeesList, eliminates duplicate email and phone records for the selected employee, and populates listboxes
I have a DataGridView which displays an employee list. I use the employee ID to filter my global employee list and display information about the selected employee in various listboxes. This is my ...
4
votes
1answer
165 views
Applying functions to decorated objects
I have an interface Animal with a class that implements it, Cat.
...
7
votes
1answer
147 views
Java service to convert xls files to HTML
I have a service that converts an Excel spreadsheet file into HTML. It is working just fine, but it is quite a big method that doesn't follow any SOLID principles. Therefore I would like to improve it ...
1
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1answer
41 views
2
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0answers
69 views
Visitor pattern, Extensible visitor for custom implementation
I'm writing my own expression tree system, just for fun, but I have a few doubts about my code.
My goal here is to create an abstract layer of expressions, and allow different "languages" to ...
2
votes
1answer
81 views
Builiding a Model from Stored Procedures
After reading that Data Classes can be considered a code smell, I am shifting from a pattern with many data classes and a single manager class that handles all the instantiation of the classes, to a ...
0
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1answer
90 views
