Search Results

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

Page 65/582 | < Previous Page | 61 62 63 64 65 66 67 68 69 70 71 72  | Next Page >

  • How does Undo work?

    - by dontWatchMyProfile
    How does undo work? Does it copy all the managed objects every time any of the values change? Or does it only copy the actual changes together with an information which objects were affected? Is that heavy or lightweight?

    Read the article

  • DB Strategy for inserting into a high read table (Sql Server)

    - by Tom
    Looking for strategies for a very large table with data maintained for reporting and historical purposes, a very small subset of that data is used in daily operations. Background: We have Visitor and Visits tables which are continuously updated by our consumer facing site. These tables contain information on every visit and visitor, including bots and crawlers, direct traffic that does not result in a conversion, etc. Our back end site allows management of the visitor's (leads) from the front end site. Most of the management occurs on a small subset of our visitors (visitors that become leads). The vast majority of the data in our visitor and visit tables is maintained only for a much smaller subset of user activity (basically reporting type functionality). This is NOT an indexing problem, we have done all we can with indexing and keeping our indexes clean, small, and not fragmented. ps: We do not currently have the budget or expertise for a data warehouse. The problem: We would like the system to be more responsive to our end users when they are querying, for instance, the list of their assigned leads. Currently the query is against a huge data set of mostly irrelevant data. I am pondering a few ideas. One involves new tables and a fairly major re-architecture, I'm not asking for help on that. The other involves creating redundant data, (for instance a Visitor_Archive and a Visitor_Small table) where the larger visitor and visit tables exist for inserts and history/reporting, the smaller visitor1 table would exist for managing leads, sending lead an email, need leads phone number, need my list of leads, etc.. The reason I am reaching out is that I would love opinions on the best way to keep the Visitor_Archive and the Visitor_Small tables in sync... Replication? Can I use replication to replicate only data with a certain column value (FooID = x) Any other strategies?

    Read the article

  • Smart card driven membership and door entry system

    - by Rob G
    I'm looking at putting in a smart card driven system at my local sports club (which doesn't have oodles of money), and since they're willing to pay for hardware, and I'm willing to do the technical setup, I was wondering if anyone had any experience in setting something like this up. Writing any software needed is not the problem, I've pretty much got that covered with various open source projects out there and custom code I'll write, but it's more the hardware side I'm not too sure about and I'm looking for advice from people out there. I'm sure there are numerous complications, but on the surface it looks fairly simple. I'd basically like to enable members to swipe/touch a smart card at the door to gain entry to the club, walk up to a touch screen PC and swipe/touch a card reader there to "login" to the system I create, which will allow them to book club facilities etc. I may even want that same card to then activate things like lights or music when they enter the room they've booked. Pretty Eutopian I know, but still, we'd like to get as close as we can. As I said, the software shouldn't be a problem, and on the hardware side, so far I'm looking at: All in one touch screen PC running Windows 7 or Ubuntu USB card reader (not sure which one to buy) Smart Cards (again, never bought these before) Door/lighting hardware that could be triggered (not sure here either) If anyone has any advice on implementing something like this - especially the items I'm not sure about above, and of course anything I've missed out that's crucial, I'd be most grateful. Recommended hardware that you've used for something like this would be fantastic!

    Read the article

  • Problem: writing parameter values to data driven MSTEST output

    - by Shubh
    Hi, I am trying to extract some information about the parameter variants used in an MSTEST data driven test case from trx file. Currently, For data driven tests, I get the output of same testcase with different inputs as a sequence of tags , but there is no info about the value of the variants. Example: Suppose we have a [data driven]TestMethod1() and the data rows contain variations a and b. There are two variations a=1,b=2 for which the test passes and a=3,b=4 for which the test fails. If we can output the info that it was a=1,b=2 which passed and a=3 b=4 which failed in the trx file; the output will be meaningful. Better information about test case runs from the output file alone(without any dependencies). Investigating the test failure without rerunning the whole set If the data rows change in data source(now a=1,b=2 pass and a=5,b=6 fail) , easy to decipher that the errors are different; although the fail sequence is still the same(row 0 pass row 1 fail but now row1 is different) Has any of you gone through a similar problem? What did you follow? I tried to put the parameter value information in the Description attribute of TestMethod, it didnt work. Any other methods you think can work too? thanks, Shubhankar

    Read the article

  • What makes them click ?

    - by Piet
    The other day (well, actually some weeks ago while relaxing at the beach in Kos) I read ‘Neuro Web Design - What makes them click?’ by Susan Weinschenk. (http://neurowebbook.com) The book is a fast and easy read (no unnecessary filler) and a good introduction on how your site’s visitors can be steered in the direction you want them to go. The Obvious The book handles some of the more known/proven techniques, like for example that ratings/testimonials of other people can help sell your product or service. Another well known technique it talks about is inducing a sense of scarcity/urgency in the visitor. Only 2 seats left! Buy now and get 33% off! It’s not because these are known techniques that they stop working. Luckily 2/3rd of the book handles less obvious techniques, otherwise it wouldn’t be worth buying. The Not So Obvious A less known influencing technique is reciprocity. And then I’m not talking about swapping links with another website, but the fact that someone is more likely to do something for you after you did something for them first. The book cites some studies (I always love the facts and figures) and gives some actual examples of how to implement this in your site’s design, which is less obvious when you think about it. Want to know more ? Buy the book! Other interesting sources For a more general introduction to the same principles, I’d suggest ‘Yes! 50 Secrets from the Science of Persuasion’. ‘Yes!…’ cites some of the same studies (it seems there’s a rather limited pool of studies covering this subject), but of course doesn’t show how to implement these techniques in your site’s design. I read ‘Yes!…’ last year, making ‘Neuro Web Design’ just a little bit less interesting. !!!Always make sure you’re able to measure your changes. If you haven’t yet, check out the advanced segmentation in Google Analytics (don’t be afraid because it says ‘beta’, it works just fine) and Google Website Optimizer. Worth Buying? Can I recommend it ? Sure, why not. I think it can be useful for anyone who ever had to think about the design or content of a site. You don’t have to be a marketing guy to want a site you’re involved with to be successful. The content/filler ratio is excellent too: you don’t need to wade through dozens of pages to filter out the interesting bits. (unlike ‘The Design of Sites’, which contains too much useless info and because it’s in dead-tree format, you can’t google it) If you like it, you might also check out ‘Yes! 50 Secrets from the Science of Persuasion’. Tip for people living in Europe: check Amazon UK for your book buying needs. Because of the low UK Pound exchange rate, it’s usually considerably cheaper and faster to get a book delivered to your doorstep by Amazon UK compared to having to order it at the local book store or web-shop.

    Read the article

  • Combining template method with strategy

    - by Mekswoll
    An assignment in my software engineering class is to design an application which can play different forms a particular game. The game in question is Mancala, some of these games are called Wari or Kalah. These games differ in some aspects but for my question it's only important to know that the games could differ in the following: The way in which the result of a move is handled The way in which the end of the game is determined The way in which the winner is determined The first thing that came to my mind to design this was to use the strategy pattern, I have a variation in algorithms (the actual rules of the game). The design could look like this: I then thought to myself that in the game of Mancala and Wari the way the winner is determined is exactly the same and the code would be duplicated. I don't think this is by definition a violation of the 'one rule, one place' or DRY principle seeing as a change in rules for Mancala wouldn't automatically mean that rule should be changed in Wari as well. Nevertheless from the feedback I got from my professor I got the impression to find a different design. I then came up with this: Each game (Mancala, Wari, Kalah, ...) would just have attribute of the type of each rule's interface, i.e. WinnerDeterminer and if there's a Mancala 2.0 version which is the same as Mancala 1.0 except for how the winner is determined it can just use the Mancala versions. I think the implementation of these rules as a strategy pattern is certainly valid. But the real problem comes when I want to design it further. In reading about the template method pattern I immediately thought it could be applied to this problem. The actions that are done when a user makes a move are always the same, and in the same order, namely: deposit stones in holes (this is the same for all games, so would be implemented in the template method itself) determine the result of the move determine if the game has finished because of the previous move if the game has finished, determine who has won Those three last steps are all in my strategy pattern described above. I'm having a lot of trouble combining these two. One possible solution I found would be to abandon the strategy pattern and do the following: I don't really see the design difference between the strategy pattern and this? But I am certain I need to use a template method (although I was just as sure about having to use a strategy pattern). I also can't determine who would be responsible for creating the TurnTemplate object, whereas with the strategy pattern I feel I have families of objects (the three rules) which I could easily create using an abstract factory pattern. I would then have a MancalaRuleFactory, WariRuleFactory, etc. and they would create the correct instances of the rules and hand me back a RuleSet object. Let's say that I use the strategy + abstract factory pattern and I have a RuleSet object which has algorithms for the three rules in it. The only way I feel I can still use the template method pattern with this is to pass this RuleSet object to my TurnTemplate. The 'problem' that then surfaces is that I would never need my concrete implementations of the TurnTemplate, these classes would become obsolete. In my protected methods in the TurnTemplate I could just call ruleSet.determineWinner(). As a consequence, the TurnTemplate class would no longer be abstract but would have to become concrete, is it then still a template method pattern? To summarize, am I thinking in the right way or am I missing something easy? If I'm on the right track, how do I combine a strategy pattern and a template method pattern? This is part of a homework assignment but I'm not looking to be gifted the answer, I have deliberately been very verbose in my question to show that I have thought about it before coming here to ask a question

    Read the article

  • Design for complex ATG applications

    - by Glen Borkowski
    Overview Needless to say, some ATG applications are more complex than others.  Some ATG applications support a single site, single language, single catalog, single currency, have a single development staff, single business team, and a relatively simple business model.  The real complex applications have to support multiple sites, multiple languages, multiple catalogs, multiple currencies, a couple different development teams, multiple business teams, and a highly complex business model (and processes to go along with it).  While it's still important to implement a proper design for simple applications, it's absolutely critical to do this for the complex applications.  Why?  It's all about time and money.  If you are unable to manage your complex applications in an efficient manner, the cost of managing it will increase dramatically as will the time to get things done (time to market).  On the positive side, your competition is most likely in the same situation, so you just need to be more efficient than they are. This article is intended to discuss a number of key areas to think about when designing complex applications on ATG.  Some of this can get fairly technical, so it may help to get some background first.  You can get enough of the required background information from this post.  After reading that, come back here and follow along. Application Design Of all the various types of ATG applications out there, the most complex tend to be the ones in the telecommunications industry - especially the ones which operate in multiple countries.  To get started, let's assume that we are talking about an application like that.  One that has these properties: Operates in multiple countries - must support multiple sites, catalogs, languages, and currencies The organization is fairly loosely-coupled - single brand, but different businesses across different countries There is some common functionality across all sites in all countries There is some common functionality across different sites within the same country Sites within a single country may have some unique functionality - relative to other sites in the same country Complex product catalog (mostly in terms of bundles, eligibility, and compatibility) At this point, I'll assume you have read through the required reading and have a decent understanding of how ATG modules work... Code / configuration - assemble into modules When it comes to defining your modules for a complex application, there are a number of goals: Divide functionality between the modules in a way that maps to your business Group common functionality 'further down in the stack of modules' Provide a good balance between shared resources and autonomy for countries / sites Now I'll describe a high level approach to how you could accomplish those goals...  Let's start from the bottom and work our way up.  At the very bottom, you have the modules that ship with ATG - the 'out of the box' stuff.  You want to make sure that you are leveraging all the modules that make sense in order to get the most value from ATG as possible - and less stuff you'll have to write yourself.  On top of the ATG modules, you should create what we'll refer to as the Corporate Foundation Module described as follows: Sits directly on top of ATG modules Used by all applications across all countries and sites - this is the foundation for everyone Contains everything that is common across all countries / all sites Once established and settled, will change less frequently than other 'higher' modules Encapsulates as many enterprise-wide integrations as possible Will provide means of code sharing therefore less development / testing - faster time to market Contains a 'reference' web application (described below) The next layer up could be multiple modules for each country (you could replace this with region if that makes more sense).  We'll define those modules as follows: Sits on top of the corporate foundation module Contains what is unique to all sites in a given country Responsible for managing any resource bundles for this country (to handle multiple languages) Overrides / replaces corporate integration points with any country-specific ones Finally, we will define what should be a fairly 'thin' (in terms of functionality) set of modules for each site as follows: Sits on top of the country it resides in module Contains what is unique for a given site within a given country Will mostly contain configuration, but could also define some unique functionality as well Contains one or more web applications The graphic below should help to indicate how these modules fit together: Web applications As described in the previous section, there are many opportunities for sharing (minimizing costs) as it relates to the code and configuration aspects of ATG modules.  Web applications are also contained within ATG modules, however, sharing web applications can be a bit more difficult because this is what the end customer actually sees, and since each site may have some degree of unique look & feel, sharing becomes more challenging.  One approach that can help is to define a 'reference' web application at the corporate foundation layer to act as a solid starting point for each site.  Here's a description of the 'reference' web application: Contains minimal / sample reference styling as this will mostly be addressed at the site level web app Focus on functionality - ensure that core functionality is revealed via this web application Each individual site can use this as a starting point There may be multiple types of web apps (i.e. B2C, B2B, etc) There are some techniques to share web application assets - i.e. multiple web applications, defined in the web.xml, and it's worth investigating, but is out of scope here. Reference infrastructure In this complex environment, it is assumed that there is not a single infrastructure for all countries and all sites.  It's more likely that different countries (or regions) could have their own solution for infrastructure.  In this case, it will be advantageous to define a reference infrastructure which contains all the hardware and software that make up the core environment.  Specifications and diagrams should be created to outline what this reference infrastructure looks like, as well as it's baseline cost and the incremental cost to scale up with volume.  Having some consistency in terms of infrastructure will save time and money as new countries / sites come online.  Here are some properties of the reference infrastructure: Standardized approach to setup of hardware Type and number of servers Defines application server, operating system, database, etc... - including vendor and specific versions Consistent naming conventions Provides a consistent base of terminology and understanding across environments Defines which ATG services run on which servers Production Staging BCC / Preview Each site can change as required to meet scale requirements Governance / organization It should be no surprise that the complex application we're talking about is backed by an equally complex organization.  One of the more challenging aspects of efficiently managing a series of complex applications is to ensure the proper level of governance and organization.  Here are some ideas and goals to work towards: Establish a committee to make enterprise-wide decisions that affect all sites Representation should be evenly distributed Should have a clear communication procedure Focus on high level business goals Evaluation of feature / function gaps and how that relates to ATG release schedule / roadmap Determine when to upgrade & ensure value will be realized Determine how to manage various levels of modules Who is responsible for maintaining corporate / country / site layers Determine a procedure for controlling what goes in the corporate foundation module Standardize on source code control, database, hardware, OS versions, J2EE app servers, development procedures, etc only use tested / proven versions - this is something that should be centralized so that every country / site does not have to worry about compatibility between versions Create a innovation team Quickly develop new features, perform proof of concepts All teams can benefit from their findings Summary At this point, it should be clear why the topics above (design, governance, organization, etc) are critical to being able to efficiently manage a complex application.  To summarize, it's all about competitive advantage...  You will need to reduce costs and improve time to market with the goal of providing a better experience for your end customers.  You can reduce cost by reducing development time, time allocated to testing (don't have to test the corporate foundation module over and over again - do it once), and optimizing operations.  With an efficient design, you can improve your time to market and your business will be more flexible  and agile.  Over time, you'll find that you're becoming more focused on offering functionality that is new to the market (creativity) and this will be rewarded - you're now a leader. In addition to the above, you'll realize soft benefits as well.  Your staff will be operating in a culture based on sharing.  You'll want to reward efforts to improve and enhance the foundation as this will benefit everyone.  This culture will inspire innovation, which can only lend itself to your competitive advantage.

    Read the article

  • Unit testing newbie team needs to unit test

    - by Walter
    I'm working with a new team that has historically not done ANY unit testing. My goal is for the team to eventually employ TDD (Test Driven Development) as their natural process. But since TDD is such a radical mind shift for a non-unit testing team I thought I would just start off with writing unit tests after coding. Has anyone been in a similar situation? What's an effective way to get a team to be comfortable with TDD when they've not done any unit testing? Does it make sense to do this in a couple of steps? Or should we dive right in and face all the growing pains at once?? EDIT Just for clarification, there is no one on the team (other than myself) who has ANY unit testing exposure/experience. And we are planning on using the unit testing functionality built into Visual Studio.

    Read the article

  • How can story and gameplay be artfully merged?

    - by NauticalMile
    Let me give some context. Three of my friends and I have a pretty good game idea cooking. It's based off of a prototype I made that's evolving into a cool game mechanic. The mechanic itself is a toy that's fun on its own, but we haven't designed any puzzles around it yet. We have a design document going, and we are answering a lot of questions about what's in the game. It's become clear early on that everyone (including myself) likes the characters and the story a lot. Considering what our favorite games are, this is unsurprising. A story driven game makes sense to me. I like the emphasis that Paper Mario: The Thousand-Year-Door, Portal 2, and Tomb Raider place on story, and I imagine our game will have a similar feel (lots of dialogue, plot twists, lovable characters). However, one team member raised this point in the design doc: I am feeling like [fleshing out the story] is our biggest hurdle right now for making more design decisions - like more specific decisions about levels etc. Is this true? I am uncertain about working on the story extensively before gameplay, and my uneasiness was reinforced when I read this question about story vs. gameplay. What I want to say is: "Let's continue to work on the story, but also start brainstorming and prototyping abstract puzzles and combat sequences, and we'll creatively match them together later." Is this a reasonable approach? If so, how much of the development of these elements should be done independently? Should I try and create a whole bunch of puzzles while my other teammates focus on story and aesthetics? Then when we have a lot of story and game 'chunks' we can match them with eachother to build something meaningful. Or should we focus on iterating individual levels as distinct units where puzzles, story, etc... are designed together? Or maybe we need to put our excitement about the story on hold and just focus on gameplay. Is there another approach to design that we can take? Am I missing something crucial? I have discussed story and gameplay because they seem the most likely to be at odds with each other, but we also have to consider user interface, music, art direction, etc... Can we design these independently as well?

    Read the article

  • Design and Print Your Own Christmas Cards in MS Word, Part 1

    - by Eric Z Goodnight
    Looking for a  little DIY fun this holiday season? Open up familiar tool MS Word and create simple, beautiful Christmas and Holiday cards, and impress your family with your crafting skills. This is the first part of a two part article. In this first section, we’ll tackle design in MS Word. In our second, we’ll cover supplies and proper printing methods to get a great look out of your dusty old inkjet. Latest Features How-To Geek ETC The How-To Geek Guide to Learning Photoshop, Part 8: Filters Get the Complete Android Guide eBook for Only 99 Cents [Update: Expired] Improve Digital Photography by Calibrating Your Monitor The How-To Geek Guide to Learning Photoshop, Part 7: Design and Typography How to Choose What to Back Up on Your Linux Home Server How To Harmonize Your Dual-Boot Setup for Windows and Ubuntu Hang in There Scrat! – Ice Age Wallpaper How Do You Know When You’ve Passed Geek and Headed to Nerd? On The Tip – A Lamborghini Theme for Chrome and Iron What if Wile E. Coyote and the Road Runner were Human? [Video] Peaceful Winter Cabin Wallpaper Store Tabs for Later Viewing in Opera with Tab Vault

    Read the article

  • Android Design - Service vs Thread for Networking

    - by Nevyn
    I am writing an Android app, finally (yay me) and for this app I need persistant, but user closeable, network sockets (yes, more than one). I decided to try my hand at writing my own version of an IRC Client. My design issue however, is I'm not sure how to run the Socket connectivity itself. If I put the sockets at the Activity level, they keeps getting closed shortly after the Activity becomes non-visible (also a problem that needs solving...but I think i figured that one out)...but if I run a "connectivity service", I need to find out if I can have multiple instances of it running (the service, that is...one per server/socket). Either that or a I need a way to Thread the sockets themselves and have multiple threads running that I can still communicate with directly (ID system of some sort). Thus the question: Is it a 'better', or at least more "proper" design pattern, to put the Socket and networking in a service, and have the Activities consume said service...or should I tie the sockets directly to some Threaded Process owned by the UI Activity and not bother with the service implementation at all? I do know better than to put the networking directly on the UI thread, but that's as far as I've managed to get.

    Read the article

  • Design pattern for animation sequence in LibGDX

    - by kevinyu
    What design pattern to use for sequence of animation that involve different actor in libGDX. For example I am making a game to choose a wolf from a group of sheeps. The first animation played when the game begin is the wolf enter the field that is filled with two sheeps.Then the wolf disguise as a sheep and goes to the center of the screen. Then the game will shuffle the sheeps. After it finished it will ask the player where is the wolf. The game wait for player input. After that the game will show animation to show the player whether their answer is right or wrong. I am currently using State design pattern. There are four states wolfEnterState,DisguiseState,ShuffleState,UserInputState, and answerAnimationState. I feel that my code is messy. I use addAction with action sequence and action completion(new Runnable()) a lot. I feel that the action sequence is getting long. Is there a better solution for this kind of problem

    Read the article

  • OO Design, how to model Tonal Harmony?

    - by David
    I have started to write a program in C++ 11 that would analyse chords, scales, and harmony. The biggest problem I am having in my design phase, is that the note 'C' is a note, a type of chord (Cmaj, Cmin, C7, etc), and a type of key (the key of Cmajor, Cminor). The same issue arises with intervals (minor 3rd, major 3rd). I am using a base class, Token, that is the base class for all 'symbols' in the program. so for example: class Token { public: typedef shared_ptr<Token> pointer_type; Token() {} virtual ~Token() {} }; class Command : public Token { public: Command() {} pointer_type execute(); } class Note : public Token; class Triad : public Token; class MajorTriad : public Triad; // CMajorTriad, etc class Key : public Token; class MinorKey : public Key; // Natural Minor, Harmonic minor,etc class Scale : public Token; As you can see, to create all the derived classes (CMajorTriad, C, CMajorScale, CMajorKey, etc) would quickly become ridiculously complex including all the other notes, as well as enharmonics. multiple inheritance would not work, ie: class C : public Note, Triad, Key, Scale class C, cannot be all of these things at the same time. It is contextual, also polymorphing with this will not work (how to determine which super methods to perform? calling every super class constructors should not happen here) Are there any design ideas or suggestions that people have to offer? I have not been able to find anything on google in regards to modelling tonal harmony from an OO perspective. There are just far too many relationships between all the concepts here.

    Read the article

  • Architectural and Design Challenges with SOA

    With all of the hype about service oriented architecture (SOA) primarily through the use of web services, not much has been said about potential issues of using SOA in the design of an application. I am personally a fan of SOA, but it is not the solution for every application. Proper evaluation should be done on all requirements and use cases prior to deciding to go down the SOA road. It is important to consider how your application/service will handle the following perils as it executes. Example Challenges of SOA Network Connectivity Issues Handling Connectivity Issues Longer Processing/Transaction Times How many of us have had issues visiting our favorite web sites from time to time? The same issue will occur when using service based architecture especially if it is implemented using web services. Forcing applications to access services via a network connection introduces a lot of new failure points to the application. Potential failure points include: DNS issues, network hardware issues, remote server issues, and the lack of physical network connections. When network connectivity issues do occur, how are the service clients are implemented is very important. Should the client wait and poll the service until it is accessible again? If so what is the maximum wait time or number of attempts it should retry. Due to the fact of services being distributed across a network automatically increase the responsiveness of client applications due to the fact that processing time must now also include time to send and receive messages from called services. This could add nanoseconds to minutes per each request based on network load and server usage of the service provider. If speed highly desirable quality attribute then I would consider creating components that are hosted where the client application is located. References: Rader, Dave. (2002). Overcoming Web Services Challenges with Smart Design: http://soa.sys-con.com/node/39458

    Read the article

  • Software Design Idea for multi tier architecture

    - by Preyash
    I am currently investigating multi tier architecture design for a web based application in MVC3. I already have an architecture but not sure if its the best I can do in terms of extendability and performance. The current architecure has following components DataTier (Contains EF POCO objects) DomainModel (Contains Domain related objects) Global (Among other common things it contains Repository objects for CRUD to DB) Business Layer (Business Logic and Interaction between Data and Client and CRUD using repository) Web(Client) (which talks to DomainModel and Business but also have its own ViewModels for Create and Edit Views for e.g.) Note: I am using ValueInjector for convering one type of entity to another. (which is proving an overhead in this desing. I really dont like over doing this.) My question is am I having too many tiers in the above architecure? Do I really need domain model? (I think I do when I exposes my Business Logic via WCF to external clients). What is happening is that for a simple database insert it (1) create ViewModel (2) Convert ViewModel to DomainModel for Business to understand (3) Business Convert it to DataModel for Repository and then data comes back in the same order. Few things to consider, I am not looking for a perfect architecure solution as it does not exits. I am looking for something that is scalable. It should resuable (for e.g. using design patterns ,interfaces, inheritance etc.) Each Layers should be easily testable. Any suggestions or comments is much appriciated. Thanks,

    Read the article

  • Which book should I pick to improve my program designs/design patterns?

    - by zxcvbnm
    I want to learn about design patterns and from what I've seen the most recommended ones are the Gang of Four's Design Patterns and Head First Design Patterns. There are also language specific books, but I never see them recommended. I suppose it ties you to whatever strengths/weaknesses are inherent to each language, so not a good idea to learn design patterns in general. The Gang of Four's book is kinda old, so I'm wondering if there isn't a better alternative out today? I've heard the Heard First one isn't quite as good. But I'm not sure why, so it's really hard to pick either one. I've see some answers on this very site recommending both, but if I can only read one, which should I pick? I've been coding for 3+ years, though I've never had a good class on this subject. Also, would a book like Code Complete help me with this? One more thing: how often are these techniques supposed to be useful? For example, this question has me wondering if this stuff is worth the trouble. And please, tell me more than just "read x". I'd like to know why you're suggesting x.

    Read the article

  • Experienced programmer, beginner at web design, tools for effective maintainable web design? [closed]

    - by Clinton
    I do quite a bit of programming in my work, which I'm comfortable with, but recently I've being trying to do some web-design for non-work related reasons. I've got a Drupal site up and running, and added some content. But they all look fairly basic. Header with some content. It doesn't look particularly polished. Anyway, as an example, what I wanted to do was make some "bubbles", each with some text in them. From a programmers point of view, say: bubble(question_text, answer_text) might expand to a box with some border, with "Question: " + question_text then "Answer: " + answer_text. Of course I'd have lots of these bubbles, but I'd like to change their look and feel in one place, so simple HTML would be a maintainable nightmare. I also want to lay them out on the screen in some fashion. I was thinking a mixture of javascript and CSS, or possibly use PHP which Drupal uses. On the other hand, I fear I might be taking a 1990s approach to this, and that there's actually tools available now that make this process a lot easier. I'm just wondering what the best approach to this sort of task is? Should I be using offline web design software and copying the code to Drupal, and if so, any recommendations? I'm sorry if my question is a bit vague, because I'm not really sure what question I should be asking. I'd appreciate if you answer and comment, and I'll try my best to be more specific as I understand more.

    Read the article

  • Design practice for securing data inside Azure SQL

    - by Sid
    Update: I'm looking for a specific design practice as we try to build-our-own database encryption. Azure SQL doesn't support many of the encryption features found in SQL Server (Table and Column encryption). We need to store some sensitive information that needs to be encrypted and we've rolled our own using AesCryptoServiceProvider to encrypt/decrypt data to/from the database. This solves the immediate issue (no cleartext in db) but poses other problems like Key rotation (we have to roll our own code for this, walking through the db converting old cipher text into new cipher text) metadata mapping of which tables and which columns are encrypted. This is simple when it's just couple of columns (send an email to all devs/document) but that quickly gets out of hand ... So, what is the best practice for doing application level encryption into a database that doesn't support encryption? In particular, what is a good design to solve the above two bullet points? If you had specific schema additions would love it if you could give details ("Have a NVARCHAR(max) column to store the cipher metadata as JSON" or a SQL script/commands). If someone would like to recommend a library, I'd be happy to stay away from "DIY" too. Before going too deep - I assume there isn't any way I can add encryption support to Azure by creating a stored procedure, right?

    Read the article

  • MVC design patterns

    - by insane-36
    I have an application and it does not use a very good structure. However it seems to me that I have tried to stick to mvc design pattern but a senior engineer claims that I have no design patterns and code are mesh. How I have structured the code : I have couple of nsmanagedobject model classes which represents model in my case and a reskit library which encapsulates the nsurlconnection and url request. I fetch the request from the view controller itself and then when the request get completed I create predicate and then populate it in tableview. Wherever I need custom view either I create it in nib or create in a custom subclass of UIView. I have use delegation pattern and notification to communication to view controller, views and block callback with restkit. But, the senior engineer is very new to ios. He has been doing it for 2 months now but he is a good java programmer. So, what is mvc pattern ? Is core data model not working as a model objects, view controller as controller and views. I dont seem to find any other places or any other cases to create my own model object since the most of the models are used as NSManagedObject subclass.

    Read the article

  • Examples of temporal database designs? [closed]

    - by miku
    I'm researching various database design for historical record keeping - because I would like to implement a prototypical web application that (excessively) tracks changes made by users and let them undo things, see revisions, etc. I'd love use mercurial or git as backend (with files as records) - since they already implement the kind of append-only changes I imagine. I tried git and dulwich (python git API) - and it went ok - but I was concerned about performance; Bi-temporal database design lets you store a row along with time periods, when this record was valid. This sure sound more performant than to operate on files on disk (as in 1.) - but I had little luck finding real-world examples (e.g. from open source projects), that use this kind of design and are approachable enough to learn from them. Revisions à la MediaWiki revisions or an extra table for versions, as in Redmine. The problem here is, that DELETE would take the whole history with it. I looked at NoSQL solutions, too. With a document oriented approach, it would be simple to just store the whole history of an entity within the document itself - which would reduce design plus implementation time in contrast to a RDBMS approach. However, in this case I'm a bit concerned about ACID-properties, which would be important in the application. I'd like ask about experiences about real-world and pragmatic designs for temporal data.

    Read the article

  • Fitting it together, database, reporting, applications in C#

    - by alvonellos
    Introduction Preamble I was hesitant to post this, since it's an application whose intricate details are defined elsewhere, and answers may not be helpful to others. Within the past few weeks (I was actually going to write a blog post about this after I finished) I've discovered that the barrier I'm encountering is one that's actually quite common for newer developers. This question is not so much about a specific thing as it is about piecing those things together. I've searched the internet far and wide, and found many tutorials on how to create applications that are kind of similar to what I'm looking for. I've also looked at hiring another, more experienced, developer to help me along, but all I've gotten are unqualified candidates that don't have the experience necessary and won't take care of the client or project like I will. I'd rather have the project never transpire than to release a solution that is half-baked. I've asked professors at my school, but they've not turned up answers to my question. I'm an experienced developer, and I've written many applications that are -- very abstractly -- close to what I'm doing, but my experiences from those applications aren't giving me enough leverage to solve this particular problem. I just hope that posting this article isn't a mistake for me to write. Project Description I have a project I'm working on for a client that is a rewrite of an application, originally written in Foxpro 2.6 by someone before me, that performs some analysis (which, sadly, I'm not allowed to disclose as per of my employment contract) on financial data. One day, after a long talk between the client and I -- where he intimately described his frustrations with all the bugs I've been hacking out of this code for 6 months now -- he told me to just rewrite it and gave me a month to write a good 1/8 of this 65k LOC Foxpro monstrosity. this 65k line of code foxpro monstrosity. It'll take me a good 3 - 6 months to rewrite this software (I know things the original programmer did not, like inheritance) going as I am right now, but I'm quickly discovering that I'm going to need to use databases. Prior to this contract I didn't even know about foxpro, and so I've had to learn foxpro on the fly, write procedures and make modifications to the database. I've actually come to like it, and this project would be rewritten in Foxpro if it were still a supported language, because over the past few months, I've come to like the features of Foxpro that make it so easy to develop data-driven applications. I once perfomed an experiment, comparing C# to Foxpro. What took me 45 minutes in C# took me two in Foxpro, and I knew C# prior to Foxpro. I was hoping to leverage the power of C#, but it intimidates me that in foxpro, you can have one line of code and be using a database. Prior to this, I have never written any serious database development from scratch. All the applications that I've written are in a different league. They are either completely data-naive or data-naive enough that I can get away with not using a database through serialization or by designing algorithms that work with the data in a manner that is stateless, so there is no need to worry about databases. I've come to realize, very quickly, that serialization and my efficacy with data structures has been my crutch all these years that's prevented me from adventuring into databases, and has consequently hindered my success in real-world programming. Sure, I've written some database stuff in Perl and Python, and I've done forms and worked with relational databases and tables, I'm a wizard in Access and Excel (seriously) and can do just about anything, but it just feels unnatural writing SQL code in another language... I don't mind writing SQL, and I don't It's that bridge between the database and the program code that drives me absolutely bonkers. I hope I'm not the only one to think this, but it bothers me that I have to create statements like the following string sSql = "SELECT * from tablename" When there's really no reason for that kind of unchecked language binding between two languages and two API's. Don't get my wrong, SQL is great, but I don't like the idea that, when executing commands on a SQL database, that one must intermix database and application software, and there's no database independence, which means that different versions of different databases can break code. This isn't very nice. The nicest thing about Foxpro is the cohesiveness between programming language and database. It's so easy, and Foxpro makes it easy, because the tool just fits the task. I can see why so many developers have created a career with this language, because it lowered the barrier of entry to data-driven applications that so many businesses need. It was wonderful. For my purposes today, with the demands and need for community support, extensibility, and language features, Foxpro isn't a solution that I feel would be the right tool for the job. I'm also worried about working too heavy with the database, because I've seen data-driven .NET applications have issues with database caches, running out of memory, and objects in the database not being collected. (Memory leaks) And OH the queries. Which one, how, and why? There are a plethora of different ways that a database can be setup, I think I counted 5 or 6 different kinds of database applications alone that I can chose from. That is a great mountain for me to climb when I don't even know where to begin when it comes to writing data-driven applications. The problem isn't that I don't know SQL or that I don't know C#. I know both and have worked with both extensively. It's making them work together that's the problem, and it's something I've never done in C# before. Reports The client likes paper. The data needs to be printed out in a format that is extensible, layered, and easy to use. I have never done reporting before, and so this is a bit of a problem. From the data source comes crystal reports, and so there's a dependency on the database, from what I understand. Code reuse A large part of the design decision that I've gone through so far is to break the task of writing a piece of this software into routines and modular DLL's and so forth such that much of the code can be reused. For example, when I setup this database, I want to be able to reuse the same database code over and over again. I also want to make sure that when the day comes that another developer is here, that he/she will be able to pick up just where I left off. The quicker I develop these applications, the better off I am. Tasks & Goals In my project, I need to write routines that apply algorithms and look for predefined patterns in financial data. Additionally, I need to simulate trading based on predefined algorithms and data. Then I need to prepare reports on that data. Additionally, I need to have a way to change the code base for this application quickly and effectively, without hacking together some band-aid solution for a problem that really needs a trauma ward. Special Considerations The solution must be fast, run quickly on existing hardware, and not be too much of a pain to maintain and write. I understand that anything I write I'm married to -- I'm responsible for the things that I write because my reputation and livelihood is dependent on it. Do I really need a database? What about performance? Performance was such a big issue that I hand wrote a data structure that is capable of performing 2 billion operations, using a total of 4 gigs of memory in under 1/4 of a second using the standard core two duo processor. I could not find a similar, pre-written data structure in C# to perform this task. What setup do I use in terms of database? What about reporting? I'd prefer to have PDF's generated, but I'd like to be able to visually sketch those reports and then just have a ReportFactory of some sort, that when I pass some variables in, it just does that data. About Me I'm a lone developer for a small business in this area. This is the first time I've done this and I've never had the breadth and depth of my knowledge tested. I'm incredibly frustrated with this project because I feel incredibly overwhelmed with the task at hand. I'm looking for that entry level point where I can draw a line and say "this is what I need to do" Conclusion I may have not been clear enough on my post. I'm still new to this whole thing, and I've been doing my best to contribute back to the community that I've leached so much knowledge from. I'd be glad to edit my post and add more information if possible. I'm looking for a big-picture solution or design process that helps me get off the ground in this world of data-driven applications, because I have a feeling that it's going to be concentric to my entire career as a programmer for some time. Specifically, if you didn't get it from the rest of the post (I may not have been clear enough) I really need some guidance as to where to go in terms of the design decisions for this project. Some things that'll be useful will be a pro/con list for the different kinds of database projects available in VS2010. I've tried, but generating that list has been as hard as solving the problem itself... If you could walk a developer writing a data-driven application for the first time in C#, how would you do that? Where would you point them to?

    Read the article

  • TDD - Outside In vs Inside Out

    - by Songo
    What is the difference between building an application Outside In vs building it Inside Out using TDD? These are the books I read about TDD and unit testing: Test Driven Development: By Example Test-Driven Development: A Practical Guide: A Practical Guide Real-World Solutions for Developing High-Quality PHP Frameworks and Applications Test-Driven Development in Microsoft .NET xUnit Test Patterns: Refactoring Test Code The Art of Unit Testing: With Examples in .Net Growing Object-Oriented Software, Guided by Tests---This one was really hard to understand since JAVA isn't my primary language :) Almost all of them explained TDD basics and unit testing in general, but with little mention of the different ways the application can be constructed. Another thing I noticed is that most of these books (if not all) ignore the design phase when writing the application. They focus more on writing the test cases quickly and letting the design emerge by itself. However, I came across a paragraph in xUnit Test Patterns that discussed the ways people approach TDD. There are 2 schools out there Outside In vs Inside Out. Sadly the book doesn't elaborate more on this point. I wish to know what is the main difference between these 2 cases. When should I use each one of them? To a TDD beginner which one is easier to grasp? What is the drawbacks of each method? Is there any materials out there that discuss this topic specifically?

    Read the article

  • How to improve designer and developer work flow?

    - by mbdev
    I work in a small startup with two front end developers and one designer. Currently the process starts with the designer sending a png file with the whole page design and assets if needed. My task as front end developer is to convert it to a HTML/CSS page. My work flow currently looks like this: Lay out the distinct parts using html elements. Style each element very roughly (floats, minimal fonts and padding) so I can modify it using inspection. Using Chrome Developer Tools (inspect) add/change css attributes while updating the css file. Refresh the page after X amount of changes Use Pixel Perfect to refine the design more. Sit with the designer to make last adjustments. Inferring the paddings, margins, font sizes using trial and error takes a lot of time and I feel the process could become more efficient but not sure how to improve it. Using PSD files is not an option since buying Photoshop for each developer is currently not considered. Design guide is also not available since design is still evolving and new features are introduced. Ideas for improving the process above and sharing how the process looks like in your company will be great.

    Read the article

  • Name for Osherove's modified singleton pattern?

    - by Kazark
    I'm pretty well sold on the "singletons are evil" line of thought. Nevertheless, there are limited occurrences when you want to limit the creation of an object. Roy Osherove advises, If you're planning to use a singleton in your design, separate the logic of the singleton class and the logic that makes it a singleton (the part that initializes a static variables, for example) into two separate classes. That way, you can keep the single responsibility principle (SRP) and also have a way to override singleton logic. (The Art of Unit Testing 261-262) This pattern still perpetuates the global state. However, it does result in a testable design, so it seems to me to be a good pattern for mitigating the damage of a singleton. However, Osherove does not give a name to this pattern; but naming a pattern, according to the Gang of Four, is important: Naming a pattern immediately increases our design vocabulary. It lets us design at a higher level of abstraction. (3) Is there a standard name for this pattern? It seems different enough from a standard singleton to deserve a separate name. Decoupled Singleton, perhaps?

    Read the article

  • Advice on choosing a book to read

    - by Kioshiki
    I would like to ask for some recommendations on useful books to read. Initially I had intended on posting quite a long description of my current issue and asking for advice. But I realised that I didn’t have a clear idea of what I wanted to ask. One thing that is clear to me is that my knowledge in various areas needs improving and reading is one method of doing that. Though choosing the right book to read seems like a task in itself when there are so many books out there. I am a programmer but I also deal with analysis, design & testing. So I am not sure what type of book to read. One option might be to work through two books at the same time. I had thought maybe one about design or practices and another of a more technical focus. Recently I came across one book that I thought might be useful to read: http://xunitpatterns.com/index.html It seems like an interesting book, but the comments I read on amazon.co.uk show that the book is probably longer than it needs to be. Has anyone read it and can comment on this? Another book that I already own and would probably be a good one to finish reading is this: http://www.amazon.co.uk/Code-Complete-Practical-Handbook-Construction/dp/0735619670/ref=sr_1_1?ie=UTF8&qid=1309438553&sr=8-1 Has anyone else read this who can comment on its usefulness? Beyond these two I currently have no clear idea of what to read. I have thought about reading a book related to OO design or the GOF design patterns. But I wonder if I am worrying too much about the process and practices and not focusing on the actual work. I would be very grateful for any suggestions or comments. Many Thanks, Kioshiki

    Read the article

< Previous Page | 61 62 63 64 65 66 67 68 69 70 71 72  | Next Page >