Search Results

Search found 14531 results on 582 pages for 'doman driven design'.

Page 75/582 | < Previous Page | 71 72 73 74 75 76 77 78 79 80 81 82  | Next Page >

  • Build one to throw away vs Second-system effect

    - by m3th0dman
    One one hand there is an advice that says "Build one to throw away". Only after finishing a software system and seeing the end product we realize what went wrong in the design phase and understand how we should have really done it. On the other hand there is the "second-system effect" which says that the second system of the same kind that is designed is usually worse than the first one; there are many features that did not fit in the first project and were pushed into the second version usually leading to overly complex and overly engineered. Isn't here some contradiction between these principles? What is the correct view over the problems and where is the border between these two? I believe that these "good practices" are were firstly promoted in the seminal book The Mythical Man-Month by Fred Brooks. I know that some of these issues are solved by Agile methodologies, but deep down, the problem is still the principles still stand; for example we would not make important design changes 3 sprints before going live.

    Read the article

  • DDD and Value Objects. Are mutable Value Objects a good candidate for Non Aggr. Root Entity?

    - by Tony
    Here is a little problem Have an entity, with a value object. Not a problem. I replace a value object for a new one, then nhibernate inserts the new value and orphan the old one, then deletes it. Ok, that's a problem. Insured is my entity in my domain. He has a collection of Addresses (value objects). One of the addresses is the MailingAddress. When we want to update the mailing address, let's say zipcode was wrong, following Mr. Evans doctrine, we must replace the old object for a new one since it's immutable (a value object right?). But we don't want to delete the row thou, because that address's PK is a FK in a MailingHistory table. So, following Mr. Evans doctrine, we are pretty much screwed here. Unless i make my addressses Entities, so i don't have to "replace" it, and simply update its zipcode member, like the old good days. What would you suggest me in this case? The way i see it, ValueObjects are only useful when you want to encapsulate a group of database table's columns (component in nhibernate). Everything that has a persistence id in the database, is better off to make it an Entity (not necessarily an aggregate root) so you can update its members without recreating the whole object graph, specially if that's a deep-nested object. Do you concur? Is it allowed by Mr. Evans to have a mutable value object? Or is a mutable value object a candidate for an Entity? Thanks

    Read the article

  • How to fix “Unit Test Runner failed to load test assembly”

    - by ybbest
    I encountered this issue a couple times during my recent project, every time I forgot what actually cause the issue. Therefore, I decide to write a quick blog post to make sure I can identify the issue quickly. Problem: Run unit test using a test runner and received a Unit Test Runner failed to load test assembly exception. Analysis: Basically, I have changed some code and start the test runner to run tests. The same dll have already been deployed to GAC. So the test runner actually tries to use the old version of the assembly thus could not load the assembly. Solution: Deploy the current version of dll to the GAC and re-run your test, it works like a charm.

    Read the article

  • Advice needed: Software Development [closed]

    - by Hunter McMillen
    I recently graduated from college with a B.S. in Computer Science, and am now currently attending the same college to get an M.S. in Computer Science. I know lots of things about Computer Science and programming but throughout all of my coursework I have never had to develop a single complete application, the projects were always relatively small (~300-500 lines of code). Basically, my overall I am about to have these two degrees and I feel like I don't know anything about software development or design; which doesn't make a whole lot of sense. I am looking for ways to fill in the gaps in my knowledge, I would love people's advice on these questions: 1) How do you design good software? Where do you start? 2) What makes a good software developer? Sorry for the convoluted question, but in my mind it is a convoluted situation. Thanks Edit Thanks everyone for your advice.

    Read the article

  • Responsive Design for your ADF Faces Web Applications

    - by Shay Shmeltzer
    Responsive web applications are a common pattern for designing web pages that adjust their UI based on the device that access them. With the increase in the number of ADF applications that are being accessed from mobile phones and tablet we are getting more and more questions around this topic. Steven Davelaar wrote a comprehensive article covering key concepts in this area that you can find here. The article focuses on what I would refer to as server adaptive application, where the server adapts the UI it generates based on the device that is accessing the server. However there is one more technique that is not covered in that article and can be used with Oracle ADF - it is CSS manipulation on the client that can achieve responsive design. I'll cover this technique in this blog entry. The main advantage of this technique is that the UI manipulation does not require the server to send over a new UI when a change is needed. This for example allows your page to change immediately when you change the orientation of your device. (By the way this example was developed for one of the seminars in the upcoming Oracle ADF OTN Virtual Developer Day). In the demo that you'll see below you'll see a single page that changes the way it is displayed based on the orientation of the device. Here is the page with the tablet in landscape and portrait: To achieve this I'm using a CSS media query in my page template that changes the display property of a couple of style classes that are used in my page. The media query has this format: @media screen and (max-width:700px) {            .narrow {                display: inline;            }            .wide {                display: none;            }            .adjustFont {                font-size: small;            }            .icon-home {                font-size: 24px;            }        } This changes the properties of the same styleClasses that are defined in my application's skin. Here is a quick demo video that shows you the full application and explains how it works. For those looking to replicate this, here are the basic files: skin1.css @charset "UTF-8";/**ADFFaces_Skin_File / DO NOT REMOVE**/@namespace af "http://xmlns.oracle.com/adf/faces/rich";@namespace dvt "http://xmlns.oracle.com/dss/adf/faces";.wide {    display: inline;}.narrow {    display: none;}.adjustFont {    font-size: large;}.icon-home {        font-family: 'UIShellUGH';    -webkit-font-smoothing: antialiased;        font-size: 36px;        color: #ffa000;} pageTemplate: <?xml version='1.0' encoding='UTF-8'?><af:pageTemplateDef xmlns:af="http://xmlns.oracle.com/adf/faces/rich" var="attrs" definition="private"                    xmlns:afc="http://xmlns.oracle.com/adf/faces/rich/component">    <af:xmlContent>        <afc:component>            <afc:description>A template that will work on phones and desktop</afc:description>            <afc:display-name>ResponsiveTemplate</afc:display-name>            <afc:facet>                <afc:facet-name>main</afc:facet-name>            </afc:facet>        </afc:component>    </af:xmlContent>    <meta name="viewport" content="width=device-width, initial-scale=1"/>    <af:resource type="css">@media screen and (max-width:700px) {            .narrow {                display: inline;            }            .wide {                display: none;            }            .adjustFont {                font-size: small;            }            .icon-home {                font-size: 24px;            }        }@font-face {            font-family: 'UIShellUGH';            src: url(data:application/x-font-woff;charset=utf-8;base64,d09GRk9UVE8AA..removed code here...AzV6b1g==)format('truetype');            font-weight: normal;            font-style: normal;        }    </af:resource>    <af:panelGroupLayout id="pt_pgl4" layout="vertical" styleClass="sizeStyle">        <af:panelGridLayout id="pt_pgl1">            <af:gridRow marginTop="5px" height="40px" id="pt_gr1">                <af:gridCell marginStart="5px" width="100%" marginEnd="5px" id="pt_gc1">                    <af:panelGroupLayout id="pt_pgl3" halign="center" layout="horizontal">                        <af:outputText value="h" id="ot2" styleClass="icon-home"/>                        <af:outputText value="HR System" id="ot3" styleClass="adjustFont"/>                    </af:panelGroupLayout>                </af:gridCell>            </af:gridRow>            <af:gridRow marginTop="5px" height="auto" id="pt_gr2">                <af:gridCell marginStart="5px" width="100%" marginEnd="5px" id="pt_gc2" halign="stretch">                    <af:panelGroupLayout id="pt_pgl2" layout="scroll">                        <af:facetRef facetName="main"/>                    </af:panelGroupLayout>                </af:gridCell>            </af:gridRow>            <af:gridRow marginTop="5px" height="20px" marginBottom="5px" id="pt_gr3">                <af:gridCell marginStart="5px" width="100%" marginEnd="5px" id="pt_gc3">                    <af:panelGroupLayout id="pt_pgl5" layout="vertical" halign="center">                        <af:separator id="pt_s1"/>                        <af:outputText value="Copyright Oracle Corp. 2013" id="pt_ot1" styleClass="adjustFont"/>                    </af:panelGroupLayout>                </af:gridCell>            </af:gridRow>        </af:panelGridLayout>    </af:panelGroupLayout></af:pageTemplateDef> Example from the page:                         <af:gridRow id="gr3">                            <af:gridCell id="gc7" columnSpan="2">                                <af:panelGroupLayout id="pgl8" styleClass="narrow">                                    <af:link text="Menu" id="l1">                                        <af:showPopupBehavior triggerType="action" popupId="p1" align="afterEnd"/>                                    </af:link>                                </af:panelGroupLayout>                                <af:panelGroupLayout id="pgl7" styleClass="wide">                                    <af:navigationPane id="np1" hint="buttons">                                        <af:commandNavigationItem text="Departments" id="cni1"/>                                        <af:commandNavigationItem text="Employees" id="cni2"/>                                        <af:commandNavigationItem text="Salaries" id="cni3"/>                                        <af:commandNavigationItem text="Jobs" id="cni4"/>                                        <af:commandNavigationItem text="Services" id="cni5"/>                                        <af:commandNavigationItem text="Support" id="cni6"/>                                        <af:commandNavigationItem text="Help" id="cni7"/>                                    </af:navigationPane>                                </af:panelGroupLayout>                            </af:gridCell>                        </af:gridRow>

    Read the article

  • Getting out of my head

    - by BenCole
    (I put this on SO, but it got a couple close votes saying it belonged here instead...) I've spent the last year as a single person team developing a rich-client application (35,000+ LoC, for what it's worth). It's currently stable and in production. However, I know that my skills were rusty at the beginning of the project, so without a doubt there are major issues to the code. At this point, most of the issues are in architecture, structure, or interactions - the easy problems, even architecture/design problems, have already been weeded out. Unfortunately, I've spent so much time with this project that I'm having a hard time thinking outside of it - approaching it from a new perspective to see the flaws deeply buried or inherent in the design. How do I step outside my head and outside my code so I can get a fresh look at this code so I can make it better? Is this less of an issue than I think it is, or is this a problem for other people as well?

    Read the article

  • When do domain concepts become application constructs?

    - by Noren
    I recently posted a question regarding recovering a DDD architecture that became an anemic domain model into a multitier architecture and this question is a follow-on of sorts. My question is when do domain concepts become application constructs. My application is a local client C# 4/WPF with the following architecture: Presentation Layer Views ViewModels Business Layer ??? Domain Layer Classes that take the POCOs with primitive types and create domain concepts (e.g. image, layer, etc) Sanity checks values (e.g. image width 0) Interfaces for DTOs Interface for a repository that abstracts the filesystem Data Access Layer Classes that parse the proprietary binary files into POCOs with primitive types by explicit knowledge of the file format Implementation of domain DTOs Implementation of domain repository class Local Filesystem Proprietary binary files When does the MyImageType domain class with Int32 width, height, and Int32[] pixels become a System.Windows.Media.ImageDrawing? If I put it in the domain layer, it seems like implemenation details are being leaked (what if I didn't want to use WPF?). If I put it in the presentation layer, it seems like it's doing too much. If I create a business layer, it seems like it would be doing too little since there are few "rules" given the CRUD nature of the application. I think all of my reading has lead to analysis paralysis, so I thought fresh eyes might lend some perspective.

    Read the article

  • Vernon's book Implementing DDD and modeling of underlying concepts

    - by EdvRusj
    Following questions all refer to examples presented in Implementing DDD In article we can see from Figure 6 that both BankingAccount and PayeeAccount represent the same underlying concept of Banking Account BA 1. On page 64 author gives an example of a publishing organization, where the life-cycle of a book goes through several stages ( proposing a book, editorial process, translation of the book ... ) and at each of those stages this book has a different definition. Each stage of the book is defined in a different Bounded Context, but do all these different definitions still represent the same underlying concept of a Book, just like both BankingAccount and PayeeAccount represent the same underlying concept of a BA? 2. a) I understand why User shouldn't exist in Collaboration Context ( CC ), but instead should be defined within Identity and Access Context IAC ( page 65 ). But still, do User ( IAC ), Moderator ( CC ), Author ( CC ),Owner ( CC ) and Participant ( CC ) all represent different aspects of the same underlying concept? b) If yes, then this means that CC contains several model elements ( Moderator, Author, Owner and Participant ), each representing different aspect of the same underlying concept ( just like both BankingAccount and PayeeAccount represent the same underlying concept of a BA ). But isn't this considered a duplication of concepts ( Evan's book, page 339 ), since several model elements in CC represent the same underlying concept? c) If Moderator, Author ... don't represent the same underlying concept, then what underlying concept does each represent? 3. In an e-commerce system, the term Customer has multiple meanings ( page 49 ): When user is browsing the Catalog, Customer has different meaning than when user is placing an Order. But do these two different definitions of a Customer represent the same underlying concept, just like both BankingAccount and PayeeAccount represent the same underlying concept of a BA? thanks

    Read the article

  • Is there a term for "Use procedures that execute a single task"?

    - by Tom
    I'm having a discussion with a fellow developer, and I'm trying to argument this in something like a short "term". SoC (Separation of Concerns) is pretty straight forward design practice, but it dwells deeper. If we want to pick on it's deep corners, we can Google it and there are plenty of articles that pop up, and after taking a glimpse, we know a lot more, and might find some examples. But, what about "Use procedures that execute a single task"? That's also a great design principle to use when writing applications and it becomes more and more rewarding, the larger the application gets. Is there a term for Use procedures that execute a single task?

    Read the article

  • C# inherit from a class in a different DLL

    - by Onno
    I need to make an application that needs to be highly modular and that can easily be expanded with new functionality. I've thought up a design where I have a main window and a list of actions that are implemented using a strategy pattern. I'd like to implement the base classes/interfaces in a DLL and have the option of loading actions from DLL's which are loaded dynamically when the application starts. This way the main window can initiate actions without having to recompile or redistribute a new version. I just have to (re)distribute new DLL's which I can update dynamically at runtime. This should enable very easy modular updating from a central online source. The 'action' DLL's all inherit their structure from the code defined in the the DLL which defines the main strategy pattern structure and it's abstract factory. I'd like to know if C# /.Net will allow such a construction. I'd also like to know whether this construction has any major problems in terms of design.

    Read the article

  • Explicitly pass context object versus injecting with IoC

    - by SonOfPirate
    I have a layered service application where the service layer delegates operations into the domain layer for execution. Many of these operations need to know the context under which they are operation. (The context included the identity of the current user, culture information, etc. received from the caller.) For example, I have an API method that returns a list of announcements. The list is based on the current user's role and each announcement is localized to their culture. The API is a thin-facade that delegates to an Application Service in my domain layer. The Application Service method obviously needs to know the context of the current request/operation as another call to the same API from another user should result in a different list. Within this method, we also have logging that uses some of the context information so we a clear understanding of the context when the operation was performed (this is especially useful if something goes wrong.) While this is a contrived example, in the real world, my Application Services will coordinate operations with many collaborative components, any number of them also needing the context information. My choice is to pass the context to the Application Service which would then pass it with any calls to collaborators or have the IoC container satisfy the dependency the Application Service and any collaborators have on the context. I am wondering if it is considered good/bad, best practices/code smell, etc. if I pass the context object as a parameter to the domain methods or if injecting the context via an IoC container is preferred. (EDIT: I should mention that the context object is instantiated per-request.)

    Read the article

  • Designing a "Grid" like object that contains game objects

    - by liortal
    I am working on a 2D game, where there's a game "board" on which other game objects are placed. This this is 2D, my starting point was to design a class that will internally use a 2d array for the actual stored game objects. This class could be simply accessed by 2 indices: (i, j) to get game objects on it. My problem is that i have no idea how to make the game "board" "propagate" its data onto its children. Design questions i ran into are: Should the children placed on the board have display properties such as size, screen position? Should the board itself dictate this information? How to update children in case the board changes some of its properties? (position, etc). Should the board be aware of the types of objects stored in it ? I have no idea how similar things such as WPF or other UI frameworks go about organizing a "container like" object that can arrange or apply certain UI properties to its children.

    Read the article

  • How to test the tests?

    - by Ryszard Szopa
    We test our code to make it more correct (actually, less likely to be incorrect). However, the tests are also code -- they can also contain errors. And if your tests are buggy, they hardly make your code better. I can think of three possible types of errors in tests: Logical errors, when the programmer misunderstood the task at hand, and the tests do what he thought they should do, which is wrong; Errors in the underlying testing framework (eg. a leaky mocking abstraction); Bugs in the tests: the test is doing slightly different than what the programmer thinks it is. Type (1) errors seem to be impossible to prevent (unless the programmer just... gets smarter). However, (2) and (3) may be tractable. How do you deal with these types of errors? Do you have any special strategies to avoid them? For example, do you write some special "empty" tests, that only check the test author's presuppositions? Also, how do you approach debugging a broken test case?

    Read the article

  • Group method parameter or individual parameter?

    - by Nassign
    I would like to ask on method parameters design consideration. I am usually deciding between using individual variables as parameters versus grouping them to a class or dictionary as one parameter. Is there such a rule when you should use individual parameter against using a class or a dictionary to group the parameter? Individual parameter - Straight forward, strongly typed Dictionary parameter - Very extensible, like HTTP request but cannot be strongly typed. Class parameter - Extensible by adding member to the class parameter, strongly typed. I am looking for a design reference on when to use which? Note: I am not sure if this question is valid in programmers but I definitely think it would be closed in stackoverflow, If it is still not valid, please point me to the proper page.

    Read the article

  • What does a Game Designer do? what skills do they need?

    - by xenoterracide
    I know someone who is thinking about getting into game design, and I wondered, what does the job game designer entail? what tools do you have to learn how to use? what unique skills do you need? what exactly is it you'd do from day to day. I may be wording this a bit wrong because I'm not sure if the college program is become a game designer or learn game design. but I think the same questions apply either way.

    Read the article

  • How to overcome fear to draw web-site template? [closed]

    - by Ricky
    I have some problem with web-site design. I can understand CSS, I use CSS grid frameworks, etc. But I can't realize my ideas. If I have some template, I can to translate it to HTML and CSS, but I don't understand how to begin with web-design for web-site from scratch. I think that I was afraid to draw or can't understand first steps. How to overcome this fear? May be some specific techniques like mind maps to streamline operations? or something else..? Or you can share what you are doing when begin. If any one have some ideas.. Thank you!

    Read the article

  • Any learning/studying material for C/C++ that use game programming as learning context out there?

    - by mac
    As most of game programming is done - I read on this very site - in C/C++ I was wondering if there is any learning/studying material for C/C++ that would target specifically game programming. I am not looking for material about "developing games" or "software architecture for games", but rather for material that uses "game programming" as the CONTEXT for introducing and illustrating C/C++ features, idioms, programming techniques, etc... With a simile: think to the GOF book on design patterns. There, they used "developing a text-editor" as a context for introducing design patterns, but the book is most definitively not a book about "developing text-editors". Thanks in advance for your time and advice! PS: My background: I am a programmer with a solid experience in OO scripting languages and only some experience in C and Assembler (on AVR microcontrollers), so I am thinking to mid-to-advanced level material, rather than tutorials for beginners, although it might be interesting to take a look to the latter ones if nothing else is available.

    Read the article

  • When dealing with a static game board, what are some methods to make it more interesting?

    - by Ólafur Waage
    Let's say you have a game board that you look at. It does not move but there is some action going on. For example Chess, Checkers, Solitaire. The game I'm working on is not one of this but it's a good reference. What are some methods you can apply to the game or the design that increases the appeal of the user to the game. Of course you can make it prettier but what are some other methods you can use? For example: Visual cues, game design changes, user interface arrangement, etc.

    Read the article

  • So with HTML5 what exactly.....is "supposed" to become phased out.

    - by Mercfh
    So I know HTML5 is the "replacement" for Flash...however it's obviously not mainstream just yet......but what else is it supposed to replace. I ask this because web-dev has always been a secret kinda side-passion of mine (even though I a firmware programmer mostly doing C/Java stuff). And anyway I want to pursue a side thing at doing web design (I know basic XHTML/CSS + some CSS3) But what exactly is I guess...."pointless" to study? JavaScript I assume will always be a huge part of web design? (HTML5 isn't replacing that is it?) What about Ajax and CSS itself?) And then there's Flash....not sure if thats really worth putting effort into? Also there's Adobe Flex/Air......I'm a bit confused if you can't tell.

    Read the article

  • How can be data oriented programming applied for GUI system?

    - by Miro
    I've just learned basics of Data oriented programming design, but I'm not very familiar with that yet. I've also read Pitfalls of Object Oriented Programming GCAP 09. It seems that data oriented programming is much better idea for games, than OOP. I'm just creating my own GUI system and it's completely OOP. I'm thinking if is data oriented programming design applicable for structured things like GUI. The main problem I see is that every type widget has different data, so I can hardly group them into arrays. Also every type of widget renders differently so I still need to call virtual functions.

    Read the article

  • Ubiquitous Language and Custom types

    - by EdvRusj
    Note that my question is referring to those attributes that even on their own already represent a concept ( ie on their own provide a cohesive meaning ). Thus such attribute needs no additional functional support and as such is self-contained. I'm also well-aware that even with self-contained attributes the custom types may prove beneficial ( for example, they give the ability to add new behavior later, when business requirements change ). Thus, my question focuses only on whether custom types for self-contained attributes really enrich Ubiquitous Language UL a) I've read that in most cases, even simple, self-contained attributes should have custom, more descriptive types rather than basic value types ( double, string ... ), because among other things, descriptive types add to the UL, while the use of basic types instead weakens the language. I understand the importance of UL, but how does having a basic type for a self-contained attribute weaken the language, since with self-contained attributes the name of the attribute already adequately describes the concept and thus contributes to the UL vocabulary? For example, the term person_age already adequately explains the concept of quantifying the number of years a person has: class Person { string person_age; } so what could we possibly gain by also introducing the term ThingAge to the UL: class person { ThingAge person_age; } thanks

    Read the article

  • When should an API favour optimization over readability and ease-of-use?

    - by jmlane
    I am in the process of designing a small library, where one of my design goals is to use as much of the native domain language as possible in the API. While doing so, I've noticed that there are some cases in the API outline where a more intuitive, readable attribute/method call requires some functionally unnecessary encapsulation. Since the final product will not necessarily require high performance, I am unconcerned about making the decision to favour ease-of-use in my current project over the most efficient implementation of the code in question. I know not to assume readability and ease-of-use are paramount in all expected use-cases, such as when performance is required. I would like to know if there are more general reasons that argue for an API design preferring (marginally) more efficient implementations?

    Read the article

  • How do I check that my tests were not removed by other developers?

    - by parxier
    I've just came across an interesting collaborative coding issue at work. I've written some unit/functional/integration tests and implemented new functionality into application that's got ~20 developers working on it. All tests passed and I checked in the code. Next day I updated my project and noticed (by chance) that some of my test methods were deleted by other developers (merging problems on their end). New application code was not touched. How can I detect such problem automatically? I mean, I write tests to automatically check that my code still works (or was not deleted), how do I do the same for tests? We're using Java, JUnit, Selenium, SVN and Hudson CI if it matters.

    Read the article

  • Clarification on the Strategy Pattern

    - by Holly
    I've just been reading through some basic design patterns, Could someone tell me if the term "strategy pattern" only applies if your implementing a completely abstract interface? What about when your children (concretes?) inherit from a parent class (the strategy?) with some implemented methods and some virtual and/or abstract functions? Otherwise the rest of the implementation, the idea that you can switch between different children at run time, is identical. This is something i'm quite familiar with, i was wondering if you would still call it the Strategy Pattern or if that term only applies to using an interface. Apologies if this question is not appropriate! Or if this is just nitpicking :) I'm still learning and i'm not really sure if design patterns are quite heavily defined within the industry or just a concept to be implemented as you like.

    Read the article

  • Is it okay to have many Abstract classes in your application?

    - by JoseK
    We initially wanted to implement a Strategy pattern with varying implementations of the methods in a commmon interface. These will get picked up at runtime based on user inputs. As it's turned out, we're having Abstract classes implementing 3 - 5 common methods and only one method left for a varying implementation i.e. the Strategy. Update: By many abstract classes I mean there are 6 different high level functionalities i.e. 6 packages , and each has it's Interface + AbstractImpl + (series of Actual Impl). Is this a bad design in any way? Any negative views in terms of later extensibility - I'm preparing for a code/design review with seniors.

    Read the article

< Previous Page | 71 72 73 74 75 76 77 78 79 80 81 82  | Next Page >