veered - Developer IT

Django Querying Question

- by Veered

If I were to have two different QuerySets in Django, both representing a ManyToMany relation with the same model, how would I find the intersections?

Basic Java Multi-Threading Question

When an object is instantiated in Java, is it bound to the thread that instantiated in? Because when I anonymously implement an interface in one thread, and pass it to another thread to be run, all of its methods are run in the original thread. If they are bound to their creation thread, is there anyway to create an object that will run in whatever thread calls it?

Read the article

Uses of Erlang in Telecom

- by user94154

I'm a web developer and a college student majoring in telecommunications. This means I'm decent at programming and I know a little about telecom networks (at a high, non-technical level). I keep reading that Erlang is used all over the telecom industry (supposedly for its performance). I'm wondering if there's anyway I can combine my programming skills with my telecommunications major with Erlang. Is most of the Erlang/telecom stuff closed source? Are there any open source telecom projects written Erlang? UPDATE: sipwiz's comment makes me think in terms of a question larger than "uses of Erlang". How can I leverage a high-level understanding of telecom networks and the telecom regulatory environment with programming. I hope this hasn't veered too off-topic for SO.

Read the article

ASP.NET MVC and NHibernate coupling

- by Ben

I have just started learning NHibernate. Over the past few months I have been using IoC / DI (structuremap) and the repository pattern and it has made my applications much more loosely coupled and easier to test. When switching my persistence layer to NHibernate I decided to stick with my repositories. Currently I am creating a new session on each method call but of course this means that I can not benefit from lazy loading. Therefore I wish to implement session-per-request but in doing so this will make my web project dependent on NHibernate (perhaps this is not such a bad thing?). I was planning to inject ISession into my repositories and create and dispose sessions on beginrequest/endrequest events (see http://ayende.com/Blog/archive/2009/08/05/do-you-need-a-framework.aspx) Is this a good approach? Presumably I cannot use session-per-request without having a reference to NHibernate in my web project? Having the web project dependent on NHibernate prompts my next (few) questions - why even bother with the repository? Since my web app is calling services that talk to the repositories, why not ditch the repositories and just add my NHibernate persistance code inside the services? And finally, is there really any need to split out into so many projects. Is a web project and an infrastructure project sufficient? I realise that I have veered off a bit from my original question but it seems that everyone seems to have their own opinion on these topics. Some people use the repository pattern with NHibernate, some don't. Some people stick their mapping files with the related classes, others have a separate project for this. Many thanks, Ben

Read the article

Else statement crashes when i enter a letter for a cin << int value

- by TimothyTech

Alright, i have a question, i veered away from using strings for selection so now i use an integer.when the user enters a number then the game progresses. if they enter a wrong character it SHOULD give the else statement, however if i enter a letter or character the system goes into an endless loop effect then crashes. is there a way to give the else statement even if the user defies the variable's type. // action variable; int c_action: if (c_action == 1){ // enemy attack and user attack with added effect buffer. /////////////////////////////////////////////////////// u_attack = userAttack(userAtk, weapons); enemyHP = enemyHP - u_attack; cout << " charging at the enemy you do " << u_attack << "damage" << endl; e_attack = enemyAttack(enemyAtk); userHP = userHP - e_attack; cout << "however he lashes back causing you to have " << userHP << "health left " << endl << endl << endl << endl; //end of ATTACK ACTION }else{ cout << "invalid actions" << endl; goto ACTIONS; }

Read the article

What to do when you need more verbs in REST

- by Richard Levasseur

There is another similar question to mine, but the discussion veered away from the problem I'm encounting. Say I have a system that deals with expense reports (ER). You can create and edit them, add attachments, and approve/reject them. An expense report might look like this: GET /er/1 => {"title": "Trip to NY", "totalcost": "400 USD", "comments": [ "john: Please add the total cost", "mike: done, can you approve it now?" ], "approvals": [ {"john": "Pending"}, {"finance-group": "Pending"}] } That looks fine, right? Thats what an expense report document looks like. If you want to update it, you can do this: POST /er/1 {"title": "Trip to NY 2010"} If you want to approve it, you can do this: POST /er/1/approval {"approved": true} But, what if you want to update the report and approve it at the same time? How do we do that? If you only wanted to approve, then doing a POST to something like /er/1/approval makes sense. We could put a flag in the URL, POST /er/1?approve=1, and send the data changes as the body, but that flag doesn't seem RESTful. We could put special field to be submitted, too, but that seems a bit hacky, too. If we did that, then why not send up data with attributes like set_title or add_to_cost? We could create a new resource for updating and approving, but (1) I can't think of how to name it without verbs, and (2) it doesn't seem right to name a resource based on what actions can be done to it (what happens if we add more actions?) We could have an X-Approve: True|False header, but headers seem like the wrong tool for the job. It'd also be difficult to get set headers without using javascript in a browser. We could use a custom media-type, application/approve+yes, but that seems no better than creating a new resource. We could create a temporary "batch operations" url, /er/1/batch/A. The client then sends multiple requests, perhaps POST /er/1/batch/A to update, then POST /er/1/batch/A/approval to approve, then POST /er/1/batch/A/status to end the batch. On the backend, the server queues up all the batch requests somewhere, then processes them in the same backend-transaction when it receives the "end batch processing" request. The downside with this is, obviously, that it introduces a lot of complexity. So, what is a good, general way to solve the problem of performing multiple actions in a single request? General because its easy to imagine additional actions that might be done in the same request: Suppress or send notifications (to email, chat, another system, whatever) Override some validation (maximum cost, names of dinner attendees) Trigger backend workflow that doesn't have a representation in the document.

Developer IT