Search Results

Search found 14074 results on 563 pages for 'programmers'.

Page 243/563 | < Previous Page | 239 240 241 242 243 244 245 246 247 248 249 250  | Next Page >

• Session serialization in JavaEE environment

  - by Ionut

  Please consider the following scenario: We are working on a JavaEE project for which the scalability starts to become an issue. Up until now, we were able to scale up but this is no longer an option. Therefore we need to consider scaling out and preparing the App for a clustered environment. Our main concern right now is serializing the user sessions. Sadly, we did not consider from the beginning the issue and we are encountering the following excetion: java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: org.apache.catalina.session.StandardSessionFacade I did some research and this exception is thrown because there are objects stored on the session which does not implement the Serializable interface. Considering that all over the app there are quite a few custom objects which are stored on the session without implementing this interface, it would require a lot of tedious work and dedication to fix all these classes declaration. We will fix all this declarations but the main concern is that, in the future, there may be a developer which will add a non Serializable object on the session and break the session serialization & replication over multiple nodes. As a quick overview of the project, we are developing using a home grown framework based on Struts 1 with the Servlet 3.0 API. This means that at this point, we are using the standard session.getAttribute() and session.setAttribute() to work with the session and the session handling is scattered all over the code base. Besides updating the classes of the objects stored on session and making sure that they implement the Serializable interface, what other measures of precaution should we take in order to ensure a reliable Session replication capability on the Application layer? I know it is a little bit late to consider this but what would be the best practice in this case? Furthermore, are there any other issues we should consider regarding this transition? Thank you in advance!

  Read the article

• Kinect office demo ideas

  - by Tedd Hansen

  I'm thinking of placing a Kinect (connected to a PC) in the office and have something fun on it. Just a small thing people can interact with. Basically I get a depthmap (image) and a color image from the Kinect which I can analyze and do stuff with. My limited imagination came up with: Count people passing by. Measure average width of people passing by. Some ball with physics people can play with. Audible alert when someone is walking too fast. Anyone have any good ideas? :)

  Read the article

• How to REALLY start thinking in terms of objects?

  - by Mr Grieves

  I work with a team of developers who all have several years of experience with languages such as C# and Java. Most of them are young enough to have been shown OOP as a standard way to develop software in university and are very comfortable with concepts such as inheritance, abstraction, encapsulation and polymorphism. Yet, many of them, and I have to include myself, still tend to create classes which are meant to be used in a very functional fashion. The resulting software is often several smaller classes which correctly represent business objects which get passed through larger classes which only supply ways to modify and use those objects (functions). Large complex difficult-to-maintain classes named Manager are usually the result of such behaviour. I can see two theoretical reasons why people might write this type of code: It's easy to start thinking of everything in terms of the database Deep down, for me, a computer handling a web request feels more like a functional operation than an object oriented operation when you think about Request Handlers, Threads, Processes, CPU Cores and CPU operations... I want source code which is easy to read and easy to modify. I have seen excellent examples of OO code which meet these objectives. How can I start writing code like this? How I can I really start thinking in an object oriented fashion? How can I share such a mentality with my colleagues?

  Read the article

• Which is more important in a web application code promotion hierarchy? production environment to repo equivalence or unidirectional propagation?

  - by ghbarratt

  Lets say you have a code promotion hierarchy consisting of several environments, (the polar end) two of which are development (dev) and production (prod). Lets say you also have a web application where important (but not developer controlled) files are created (and perhaps altered) in the production environment. Lets say that you (or someone above you) decided that the files which are controlled/created/altered/deleted in the production environment needed to go into the repository. Which of the following two sets of practice / approaches do you find best: Committing these non-developed file modifications made in the production environment so that the repository reflects the production environment as closely and as often as possible. Generally ignoring the non-developed production environment alterations, placing confidence in backups to restore the production environment should it be harmed, and keeping a resolution to avoid pushing developments through the promotion hierarchy in the reverse direction (avoiding pushing from prod to dev), only committing the files found in the production environment if they were absolutely necessary in other environments for development. So, 1 or 2, and why? PS - I am currently slightly biased toward maintaining production environment to repository equivalence (option 1), but I keep an open mind and would accept an answer supporting either.

  Read the article

• Should a stack trace be in the error message presented to the user?

  - by Vilx-

  I've got a bit of an argument at my workplace and I'm trying to figure out who is right, and what is the right thing to do. Context: an intranet web application that our customers use for accounting and other ERP stuff. I'm of the opinion that an error message presented to the user (when things crash) should include as much information as possible, including the stack trace. Of course, it has to start with a nice "An Error has occurred, please submit the below information to the developers" in large, friendly letters. My reasoning is that a screenshot of the crashed application will often be the only easily available source of information. Sure, you can try to get a hold of the client's systems administrator(s), attempt to explain where your log files are, etc, but that will probably be slow and painful (talking to the client representatives mostly is). Also, having an immediate and full information is extremely useful in development, where you don't have to go hunting through the log files to find what you need on every exception. (But that could be solved with a configuration switch.) Unfortunately there has been some kind of "Security audit" (no idea how they did that without the sources... but whatever), and they complained about the full exception messages citing them as a security threat. Naturally, the clients (at least one that I know of) has taken this at face value and now demands that the messages be cleaned. I fail to see how a potential attacker could use a stack trace to figure anything out he couldn't have figured out before. Are there any examples, any documented proof of anyone ever doing that? I think that we should fight this foolish idea, but perhaps I'm the fool here, so... Who's right?

  Read the article

• Recommened design pattern to handle multiple compression algorithms for a class hierarchy

  - by sgorozco

  For all you OOD experts. What would be the recommended way to model the following scenario? I have a certain class hierarchy similar to the following one: class Base { ... } class Derived1 : Base { ... } class Derived2 : Base { ... } ... Next, I would like to implement different compression/decompression engines for this hierarchy. (I already have code for several strategies that best handle different cases, like file compression, network stream compression, legacy system compression, etc.) I would like the compression strategy to be pluggable and chosen at runtime, however I'm not sure how to handle the class hierarchy. Currently I have a tighly-coupled design that looks like this: interface ICompressor { byte[] Compress(Base instance); } class Strategy1Compressor : ICompressor { byte[] Compress(Base instance) { // Common compression guts for Base class ... // if( instance is Derived1 ) { // Compression guts for Derived1 class } if( instance is Derived2 ) { // Compression guts for Derived2 class } // Additional compression logic to handle other class derivations ... } } As it is, whenever I add a new derived class inheriting from Base, I would have to modify all compression strategies to take into account this new class. Is there a design pattern that allows me to decouple this, and allow me to easily introduce more classes to the Base hierarchy and/or additional compression strategies?

  Read the article

• Need suggestion for Mutiple Windows application design

  - by King Chan

  This was previously posted in StackOverflow, I just moved to here... I am using VS2008, MVVM, WPF, Prism to make a mutiple window CRM Application. I am using MidWinow in my MainWindow, I want Any ViewModel would able to make request to MainWindow to create/add/close MidChildWindow, ChildWindow(from WPF Toolkit), Window (the Window type). ViewModel can get the DialogResult from the ChildWindow its excutes. MainWindow have control on all opened window types. Here is my current approach: I made Dictionary of each of the windows type and stores them into MainWindow class. For 1, i.e in a CustomerInformationView, its CustomerInformationViewModel can execute EditCommand and use EventAggregator to tell MainWindow to open a new ChildWindow. CustomerInformationViewModel: CustomerEditView ceView = new CustomerEditView (); CustomerEditViewModel ceViewModel = CustomerEditViewModel (); ceView.DataContext = ceViewModel; ChildWindow cWindow = new ChildWindow(); cWindow.Content = ceView; MainWindow.EvntAggregator.GetEvent<NewWindowEvent>().Publish(new WindowEventArgs(ceViewModel.ViewModeGUID, cWindow )); cWindow.Show(); Notice that all my ViewModel will generates a Guid for help identifies the ChildWindow from MainWindow's dictionary. Since I will only be using 1 View 1 ViewModel for every Window. For 2. In CustomerInformationViewModel I can get DialogResult by OnClosing event from ChildWindow, in CustomerEditViewModel can use Guid to tell MainWindow to close the ChildWindow. Here is little question and problems: Is it good idea to use Guid here? Or should I use HashKey from ChildWindow? My MainWindows contains windows reference collections. So whenever window close, it will get notifies to remove from the collection by OnClosing event. But all the Windows itself doesn't know about its associated Guid, so when I remove it, I have to search for every KeyValuePair to compares... I still kind of feel wrong associate ViewModel's Guid for ChildWindow, it would make more sense if ChildWindow has it own ID then ViewModel associate with it... But most important, is there any better approach on this design? How can I improve this better?

  Read the article

• PHP - "tabulate" array - make levels from elements

  - by Moha

  If I have an array like this: Array ( [0] => field_schools [1] => und [2] => 0 [3] => field_school [4] => und [5] => 0 [6] => value ) How can I make an array like this from it? array ( [field_schools] => array ( [und] => array ( [0] => array ( [field_school] => array ( [und] => array ( [0] => array ( [value] => something ) ) ) ) ) ) ) I want to specify the 'value' myself.

  Read the article

• Given a project and working with 1 other person - never worked with someone before

  - by Celeritas

  I'm taking a class where I work with a partner to implement the link layer of the OSI model. I've worked programmed with a partner once before and it went bad. Is the goal to divide the work up and decides who does what or should one person code and the other person reviews and switch roles after a while? Any tips are much appreciated. Literally I know nothing about working with a partner to program so even if it's basic please tell me.

  Read the article

• How far has a bug pushed you? [closed]

  - by Darknight

  When debugging (hard to find) bugs, I know I've personally gotten so frustrated as to lash out on the keyboard and shout profanities at the monitor. I have repeatability witnessed co-workers throw their computer mouse off the table in anger and frustration. What is the furthest a bastard of bug has ever pushed you? EDIT: Hehehe :D it would seem this bug, er I mean post has pushed the guys to close it... Oh well, very very interesting answers anyway.

  Read the article

• Agile project management, agile development: early integration

  - by Matías Fidemraizer

  I believe that agile works if everything is agile. In software development area, in my opinion, if team members' code is integrated early, code will be more in sync and this has a lot of pros: Early integration helps team members to avoid painful merges. Encourages better coding habits, because everyone makes sure that they don't break co-workers' code everyday. Both developers and architects (code reviewers) may detect bad design decisions or just wrong development directions in real-time, preventing useless work. Actually I'm talking about getting the latest version of code base and checking-in your own code to the source control in a daily basis. When you start your coding day (i.e. you arrive to your work), your first action is updating your code base with the latest version from the source control. In the other hand, when you're about an hour to leave from your work and go home, your last action is checking-in your code to the source control and be sure that your day work doesn't break the project's build process. Rather than updating and checking-in your code once you finished an entire task, I believe the best approach is fixing small and flexible personal milestones and checking-in the code once you finish one of these. I really believe that this coding approach fits better in the agile project management concept. Do you know some document, blog post, wiki, article or whatever that you can suggest me that could be in sync with my opinion?. And, do you find any problem working with this approach?. Thank you in advance.

  Read the article

• Software development magazines [closed]

  - by Sebastian

  Ive spent the last hour or so browsing the web for professional development magazines. I am mostly interested in the java platform, agile methods, "programming in general" (tutorials on languages or whatever, "hot new stuff" etc) and software craftmanship. My best finding yet was pragpub and maybe MSDN magazine. I am willing to pay and have a Zinio account if anyone knows a magazine about programming that is distributed by them. Ive already browsed a couple of related threads here on stackexchange. ACM and IEEE does not seem relevant, as Im not interested in research articles. Maybe conferences like OOPSLA as somebody mentioned in another thread. PS. I prefer if they are in pdf or readable on kindle or a tablet. DS. BR Sebastian

  Read the article

• Will dolphins die if I use REST "as CRUD"?

  - by l0l0l0l0l

  Recently I moved to Laravel and I was surprised on how good setting the controllers as RESTful is, it made routes and my code cleaner. I'm kinda new on web development and never used REST before since all my clients' projects are basically CRUD operations. There's any cool buzzword to this "approach" or I'm just stupid for doing it? I don't plan to follow any REST patterns, just to make my life easier and code cleaner. Basicallly just GET/POST, the other ones are not native anyway so (emulated on hidden form value).

  Read the article

• IS it ok to use REST for CRUD operations?

  - by l0l0l0l0l

  Recently I moved to Laravel and I was surprised on how good setting the controllers as RESTful is, it made routes and my code cleaner. I'm kinda new on web development and never used REST before since all my clients' projects are basically CRUD operations. Are there any cool buzzword to this "approach" or I'm just stupid for doing it? I don't plan to follow any REST patterns, just to make my life easier and code cleaner. Basically just GET/POST, the other ones are not native anyway so (emulated on hidden form value).

  Read the article

• I'm a CS student, and honestly, I don't understand Knuth's books

  - by Raymond Ho

  I stumbled upon this quote from Bill Gates: "You should definitely send me a resume if you can read the whole thing." He was talking about The Art of Programming books. So I was pretty curious and want to read it all. But honestly, I don't understand it. I'm really not that intellectual. So this should be the reason why I can't understand it, but I am eager to learn. I'm currently reading Volume 1 about fundamental algorithms. Are there any books out there that are friendly for novices/slow people like me, which would help to build up my knowledge so that I can read Knuth's book with ease in the future?

  Read the article

• Starting my first project and have no idea about it. Guide please.

  - by Chankey Pathak

  I am a Computer Science student (6th semester). I want to make a project and I have a team of 4 people (My friends). So we are 5 people and we have decided to make a "Web based file explorer". The project will be similar to THIS one. How should we start with this project? We guys don't know much about programming. I know Java a little and I am a RHCE so can handle the server and all such administrative stuffs. Since this is our first project so we guys have no idea how we'll make it? I know Java and other guys in the group knows C#, ASP.NET, PHP, SQL and Joomla. Please guide and give your suggestions. Thank you. PS : Perhaps my question is not complete, if you want more information then leave a comment I will edit the question.

  Read the article

• PDF or ebook Java API documentation

  - by AmaDaden

  Since I have a long train ride to and from work I was wondering if there is a version of the Java API documentation floating around that I could put on my Kindle. It would be nice on the rare occasion I get something in my head that I want to think about some more. I know I can browse the web through the Kindle but coverage is spotty and slow. I know that the api docs are not really designed for a sequential reading format but I'm curious to see if anyone else has thought about this and given it a shot.

  Read the article

• How to build a team of people not working together?

  - by Bernd

  I am in charge of a group of about 30 software development experts and architects. While these people are co-located in the companies organization chart, they do not really feel as a team. This is due to their work enviroment: 1) The people are spread over eight locations, with a max. distance of about 1000km (this is Europe). 2) The people don't work as team but instead get called as single people (and sometimes small groups into projects for as long as the projects run. 3) Travelling is somewhat limited as this requires business reasons. Lot is done via phone. Do you have ideas or suggestions on how I could make these people feeling part of a joint organization where they support others and get supported by others. So that they get to know their peers, build a network, informally exchange information? So that they generally get the feeling of having common ground and derive motivation and job satisfaction?

  Read the article

• Best solution for getting referral information in PHP

  - by absentx

  I am currently redoing some link structuring on a website. In the past we have used specific php files on the last step to direct the user to the proper place. Example: www.mysite.com/action/go-to-blue.php or www.mysite.com/action/short/go-to-red.php www.mysite.com/action/tall/go-to-red.php We are now restructuring to eliminate the /short/ or /tall/ directory. What this means is now "go-to-blue.php" will be doing some extra processing to make sure it sends the visitor to the proper place. The static method of the past was quite effective, because, well, if they left from that page we knew we had it right. Now since we are 301 redirecting action/short/go-to-red.php to just action/go-to-red.php it is quite important on "go-to-red.php" that we realize a user may have been redirected from /short/ or /tall/. So right now I am using HTTP_REFERRER and of course in my testing that works fine, but after a lot of reading it is clear that this is not a solid solution, so I was starting to brainstorm on other ways to check and make sure we get the proper referral information. If we could check HTTP_REFERRER plus some other test, I would feel confident we have a pretty good system in place to send the visitor to the right place. Some questions/comments: Could I use a session variable or a cookie to accomplish this goal? If so, would that be maintained through the 301 redirect? I don't see why it wouldn't be.. Passing the url in the url is not an option in this case.

  Read the article

• GSL Uniform Random Number Generator

  - by Jamaia

  I want to use GSL's uniform random number generator. On their website, they include this sample code: #include <stdio.h> #include <gsl/gsl_rng.h> int main (void) { const gsl_rng_type * T; gsl_rng * r; int i, n = 10; gsl_rng_env_setup(); T = gsl_rng_default; r = gsl_rng_alloc (T); for (i = 0; i < n; i++) { double u = gsl_rng_uniform (r); printf ("%.5f\n", u); } gsl_rng_free (r); return 0; } However, this does not rely on any seed and so, the same random numbers will be produced each time. They also specify the following: The generator itself can be changed using the environment variable GSL_RNG_TYPE. Here is the output of the program using a seed value of 123 and the multiple-recursive generator mrg, $ GSL_RNG_SEED=123 GSL_RNG_TYPE=mrg ./a.out But I don't understand how to implement this. Any ideas as to what modifications I can make to the above code to incorporate the seed?

  Read the article

• Google Closure Compiler - what does the name mean?

  - by mikez302

  I am curious about the Google Closure Compiler. Why did they name it that? Does it have anything to do with lexical closures? EDIT: I tried researching it in the FAQ and documentation, as well as doing Google searches such as "closure compiler name". I couldn't find anything definite, hence the reason I am asking. I don't think I will get a profoundly helpful answer but I was hoping that I could at least satisfy my curiosity. I am not trying to solve a specific problem. I am just curious.

  Read the article

• Modelling work-flow plus interaction with a database - quick and accessible options

  - by cjmUK

  I'm wanting to model a (proposed) manufacturing line, with specific emphasis on interaction with a traceability database. That is, various process engineers have already mapped the manufacturing process - I'm only interested in the various stations along the line that have to talk to the DB. The intended audience is a mixture of project managers, engineers and IT people - the purpose is to identify: points at which the line interacts with the DB (perhaps going so far as indicating the Store Procs called at each point, perhaps even which parameters are passed.) the communication source (PC/Handheld device/PLC) the communication medium (wireless/fibre/copper) control flow (if leak test fails, unit is diverted to repair station) Basically, the model will be used as a focus different groups on outstanding tasks; for example, I'm interested in the DB and any front-end app needed, process engineers need to be thinking about the workflow and liaising with the PLC suppliers, the other IT guys need to make sure we have the hardware and comms in place. Obviously I could just improvise in Visio, but I was wondering if there was a particular modelling technique that might particularly suit my needs or my audience. I'm thinking of a visual model with supporting documentation (as little as possible, as much as is necessary). Clearly, I don't want something that will take me ages to (effectively) learn, nor one that will alienate non-technical members of the project team. So far I've had brief looks at BPMN, EPC Diagrams, standard Flow Diagrams... and I've forgotten most of what I used to know about UML... And I'm not against picking and mixing... as long as it is quick, clear and effective. Conclusion: In the end, I opted for a quasi-workflow/dataflow diagram. I mapped out the parts of the manufacturing process that interact with the traceability DB, and indicated in a significantly-simplified form, the data flows and DB activity. Alongside which, I have a supporting document which outlines each process, the data being transacted for each process (a 'data dictionary' of sorts) and details of hardware and connectivity required. I can't decide whether is a product of genius or a crime against established software development practices, but I do think that is will hit the mark for this particular audience.

  Read the article

• Presenting agile estimates for Pivotal Tracker project

  - by Tom Styles

  I've been developing for 6-7 years but never in a particularly agile way. With the latest project I'm trying to make our development process more professional, and more agile. We're using Pivotal Tracker to track the project and have gathered some pretty well thought out stories. We're also trying to keep some of our (Prince2/Waterfall mindset) project managers happy. So far I've got them to accept that requirements always change priorities always change some of the requirements won't be delivered if you fix the time scale you should fix the time scale short sprints and regular review is good However they still feel like they need to get a better grip of roughly how much will be delivered within a certain time. I've come up with a spreadsheet to demonstrate what we might expect to get done in a range of 4 different timescales. Questions Are we setting ourselves up to fail Are there better ways to do this

  Read the article

• What are some good Software Engineering books for people who didn't formally study Computer Science or Software Engineering?

  - by Kugathasan Abimaran

  I'm a graduate in the electronic & telecommunication field, but working in a software company. I want to continue in this field and going for Masters in it. Can you recommend me some of the best books on software engineering, which cover almost all the topics in software engineering. I am not looking for books about coding practices such as Code Complete, Pragmatic Programmer, but rather general software engineering references.

  Read the article

• MCTS certification (Windows Communication Foundation Development)

  - by Pinchy

  Hi guys! I seriously need some advice on getting MCTS certified (Windows Communication Foundation Development) I just cannot go to a MS certification courses as they are very expensive here and far from my hometown. I want to self educate myself and I don't know where to start with. My problem is finding good study materials and sample exam questions. I haven't taken any Microsoft exams before so I have got no idea what they would ask me on the exam (70-513). Can anyone give me some ideas on how to start from scratch? Any answer will be much appreciated. Thanks

  Read the article

< Previous Page | 239 240 241 242 243 244 245 246 247 248 249 250  | Next Page >