4
votes
5answers
1k views

Is this a good practice or not?

I have a colleague who has come up with a way of 'genericizing' information from a database so that all his web application's drop-down lists can share the same object in his MVC.NET C# code and ...
0
votes
0answers
77 views

Result Object vs. Exceptions [on hold]

Related to this question I posted earlier: Returning results of method on batch list? I stumbled across an interesting idea at: https://www.braintreepayments.com/docs/java/general/result_objects ...
4
votes
3answers
74 views

Returning results of method on batch list?

The title is a bit vague so I'll try to elaborate. I have a function makeFoo(int bar) -> returns Foo or throws Exception. I also have a batch version of this makeFoos(int[] bars) -> ...
0
votes
0answers
78 views

How to design extension mechanism for java app

I have an application where I have a set of core features. The application itself HAS to work in core only mode. I would also want to make the application extensible such that, when certain ...
0
votes
1answer
67 views

Implement RPC via SIP

Look at the following use case. I have a client (Java) application, which wants to get/set the state of another, remote application (C). The communication between them is done via SIP, which is run ...
-1
votes
1answer
147 views

All programming functions always return to the If or If/Else statement? [closed]

After learning, coding, and coding even more than ever now, I have noticed a trend in a lot of programming which I do. The trend is that the majority of my functions are if{} or if{} else{} statements ...
2
votes
1answer
148 views

Working with a large, messy object [duplicate]

I have been handed a very cluttered, "One Ring" object (one object to rule them all). The OR class has 40 fields. These fields map to 16 different objects (the OR has all the fields from the 16 ...
2
votes
1answer
91 views

How do you show the exception handler in a class diagram?

I have one exception handler class. I want to show this class in the uml -- class diagram. But, I do not know how to represent relationship between class <X> and exception handler class. How can ...
0
votes
2answers
126 views

How to present a stable data model in a public API that allows internal data structures to be changed without breaking the public view of the data?

I am in the process of developing an application that allows users to write C# scripts. These scripts allow users to call selected methods and to access and manipulate data in a document. This works ...
2
votes
1answer
172 views

Is there a Design Pattern for preventing dangling references?

I was thinking about a design for custom handles. The thought is to prevent clients from copying around large objects. Now a regular handle class would probably suffice for that, but it doesn't solve ...
2
votes
4answers
207 views

Callbacks: when to return value, and when to modify parameter?

When writing a callback, when is best to have the callback return a value, and when is it best to have the callback modify a parameter? Is there a difference? For example, if we wanted to grab a list ...
1
vote
1answer
44 views

Handling Types for Real and Complex Matrices in a BLAS Wrapper

I come from a C background and I'm now learning OOP with C++. As an exercise (so please don't just say "this already exists"), I want to implement a wrapper for BLAS that will let the user write ...
0
votes
2answers
215 views

How to design console application with good seperation of UI from Logic

Is it considered an overkill for console application to be design like MVC , MVP or N tier architecture? If not which is more common and if you can link me to simple example of it. I want to ...
1
vote
2answers
121 views

Flags with deferred use

Let's say I have a system. In this system I have a number of operations I can do, but all of these operations have to happen as a batch at a certain time, while calls to activate and deactivate these ...
9
votes
2answers
217 views

Using packages (gems, eggs, etc.) to create decoupled architectures

The main issue Seeing the good support most modern programming platforms have for package management (think gem, npm, pip, etc), does it make sense to design an application or system be composed of ...
2
votes
1answer
185 views

Best practice to collect information from child objects

I'm regularly facing following pattern: public abstract class BaseItem { BaseItem[] children; // ... public void DoSomethingWithStuff() { StuffCollection collection = new ...
3
votes
1answer
156 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, ...
0
votes
1answer
170 views

pattern to share objects between API and application

I'm having serious doubts about the design for my Web application. I wanted to separate the business logic from the interface so I made a Web API that handles all the requests to the database. It's ...
2
votes
1answer
137 views

Adapter Pattern: Design Patterns

So far as I know, there are two forms of the Adapter Pattern: the class adapter and the object adapter. Could someone please explain to me the following limitation of the class adapter and why it is ...
0
votes
0answers
25 views

Organizing an image processing pipeline for on-the-fly video analysis

I'm trying to design a system that performs image analysis on video streams from the internet. I have a few rudimentary ideas for how to organize such a system, and I was hoping you guys could ...
3
votes
1answer
79 views

Access items of a container with a pattern

I've two C++ classes with a relation: a container class which has a list of items. For example a library has got many books. The classes are the library and the book. Now from the external world I ...
2
votes
2answers
209 views

What do I gain by using the Strategy pattern in this case?

I wrote a program with Java that plays simple music. Currently chords have only one way ('strumming pattern') to be played. I want to expand this and create different 'strumming patterns' that chords ...
0
votes
1answer
73 views

MVC: Where should I store interchangeable algorithms used by the Model (whose names also need to be accessible to the View)?

Please consider a program, where the user chooses an algorithm from a list, and the Strategy pattern is utilized to set this algorithm as the model's operation. For example, an image procession ...
2
votes
0answers
78 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 ...
0
votes
2answers
213 views

Can this argument be enough?

We have two C++ classes named Important and Small The class Small use a few methods and attributes from the class Important, but not all. Since our application is performance critical, instead of ...
1
vote
2answers
180 views

Using the Decorator pattern to add public methods to an object

The Decorator pattern is usually used to extend the functionality of an object by extending one of it's current methods. To illustrate, please consider an object object and a decorator decorator. ...
2
votes
2answers
131 views

Refactoring sought for replacing shared data types in .NET component

I am in charge with updating a software product that is made up of two components the Controller process and the UI process. The Controller and the UI communicate via XML messages. Furthermore, the ...
1
vote
1answer
132 views

Differentiating between Factory Method and Abstract Factory

I've been confused for a while about the differences between the patterns Factory Method and Abstract Factory. Been doing a lot of research, still confused. I have one question: Is the only ...
0
votes
2answers
74 views

Container/Item pattern without `friend`

I have a class Container containing objects of type Item. They are different classes, and especially they have no common base class (e.g. a Container does not itself have a Container).: class ...
0
votes
1answer
175 views

Observer pattern: “Web of observers” - Is this ever in use?

I had an idea (which I'm sure already exists), to create a sort of 'network of observers/subjects'. I would like to describe how it works and than ask several questions about it. Say we have 5 ...
0
votes
1answer
60 views

Contradiction of layered design and global data access for analytics reporting

While developing an application (mobile app for Android), our team always strives to use best development practices such as interfaces, layering and separation of concerns. When it comes to reporting ...
2
votes
3answers
236 views

How does Observer create loosely-coupled design?

I completely understand the Observer design pattern, what it is for and how to implement it. I also understand what the term 'loosely-coupled' means. But I'm not sure how Observer makes designs more ...
0
votes
1answer
110 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: ...
-1
votes
1answer
106 views

Should We Use Surrogate Primary Keys for Every Table? [duplicate]

We are developing a data model for a marketing database that will import transaction, customer, inventory, etc. files and the directive is ONE process that works for every client. We have been told ...
4
votes
5answers
253 views

How to design my code so that it can use alternative information to help create an object

I have a class named Product, which takes a product model number and number of wheels for that product as part of its creation information, and then it instantiates the product by doing a computation ...
0
votes
1answer
123 views

Why can't the Factory Method pattern create a family of objects? [duplicate]

There are two main differences between the design patterns Factory Method and Abstract Factory. Difference 1 is that Factory Method is mainly based on inheritance. A class in a way uses it's subclass ...
0
votes
0answers
20 views

Composite repository with plugins for multitenant app

Im working on an app that has flexible storage configuration. For example: public class Repo1:IRepository { public void DoSomething(int tenantId, string someKey) { ... } } This ...
0
votes
0answers
60 views

Difference between class clusters and abstract factory in cocoa

I have read that Obj-C class clusters are an implementation of the abstract factory. Can anyone explain if there are any differences between the 2 as design patterns. I read somewhere that there are ...
1
vote
5answers
628 views

How do I deal with global variables in existing legacy code (or, what's better, global hell or pattern hell)?

So... We have this fairly complex project (~10k LOC, but there's duplicated code so it's hard to tell) with hundreds of global variables. The project has more dependencies on other projects, and many ...
1
vote
2answers
141 views

Validating objects with each other - Design Pattern needed

I am running a zoo application. My zoo includes an abstract class of 'animal', and several deriving classes - 'zebra', 'elephant', 'orangutan', 'baboon' and so on. Of each class I have several ...
3
votes
1answer
222 views

Is it bad to have classes as properties of all other classes?

I've been making MVC programs for work (I'm an intern) and I feel like I'm doing a pretty good job at abstraction, single responsibility, etc. But I have this feeling about how I keep making objects ...
3
votes
1answer
155 views

implementing dynamic query handler on historical data

EDIT : Refined question to focus on the core issue Context: I have historical data about property (house) sales collected from various sources in a centralized/cloud data source (assume info ...
2
votes
2answers
207 views

Pattern for multiple datasources

I've already read this question on CodeReview. I was hoping for general advice. I'm writing a service which will go to numerous data sources. Each source requires getting copious amounts of data ...
0
votes
0answers
29 views

DSL enabling users to reference forms and records to display?

There are three main "unique" components to my system: Visual form builder (AngularJS backed); generates an id CRUD automatically available for it at /form_type/id "Aggregate page"; with a form ...
5
votes
1answer
240 views

Layers and layers of SOAP

I am designing the back-end to a SOAP web-service and have a question about how I am thinking of doing it. I am going to go with a simple layered design which consists of 3 separate layers. Layer 1 ...
0
votes
1answer
68 views

Pythonic design for controlling multiple devices through an I2C bus

I'm writing a piece of software in python that will communicate with a bunch of devices via an I2C bus. Each of these devices are going to need some sort of a module or class to handle the ...
20
votes
2answers
3k views

How to improve upon Bloch's Builder Pattern, to make it more appropriate for use in classes that may be extended and sub-extended many times over?

I have been greatly influenced by Joshua Bloch's Effective Java book (2nd edition), probably more so than with any programming book I've read. In particular, his Builder Pattern (item 2) has had the ...
0
votes
1answer
172 views

Design and write my own logger engine [closed]

I know that in this way I could reinventing the wheel, but my logging needs are quite unusual and I don't know how to achieve this unusual result with log4net, last (but not the least) I would catch ...
1
vote
1answer
303 views

Creating a online database creator

I've been thinking of creating an online database creator (think DabbleDB, Zoho Creator, Intuit Quickbase, etc.). I've been thinking of a couple solutions: Have 4 database tables: Tables, Rows, ...
0
votes
1answer
213 views

Email Content creation | Proper design

Working on an E commerce application where we need to send so many email to customer like Registration email Forget Password Order placed There are many other emails that can be sent, I already ...