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  • Upgrade .NET 1.1 WinForm/Service to what?

    - by Conor
    Hi Folks, We have a current WinForm/Windows Service running in .NET 1.1 out on various customer sites that is getting data from internal systems, transforming it and then calling a Web Service synchronously. This client app will no longer work in Vista or Windows 7 etc.. and its time to update!! I was looking for ideas on what I could do here, I didn't write the App and I have the Business team telling me they want the world but I need to be realistic :) Things the service must be able to do: - Handle multiple formats from internal system and transform to a schema SAP, ERP etc.. - Run silently and just work on customer sites (it does currently albeit .NET 1.1) - The Customers are unable to call our web service from their sites as they are not technical enough. - Upgrade it's self when updates occur (currently don't have this capability) Is there anything I can do here other than upgrade the service to run in .NET and add a few more transformation capabilities e..g they want the customer to be able to give us a flat file, an xml file, a csv and the service transforms it and calls the Web Service? I was hoping in this day and age we could use the Web, but automating this 100% rules it out in my eyes? I could be totally wrong!! Any help would be gratefully appreciated! Cheers. Conor

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  • Risking the exception anti-pattern.. with some modifications

    - by Sridhar Iyer
    Lets say that I have a library which runs 24x7 on certain machines. Even if the code is rock solid, a hardware fault can sooner or later trigger an exception. I would like to have some sort of failsafe in position for events like this. One approach would be to write wrapper functions that encapsulate each api a: returnCode=DEFAULT; try { returnCode=libraryAPI1(); } catch(...) { returnCode=BAD; } return returnCode; The caller of the library then restarts the whole thread, reinitializes the module if the returnCode is bad. Things CAN go horribly wrong. E.g. if the try block(or libraryAPI1()) had: func1(); char *x=malloc(1000); func2(); if func2() throws an exception, x will never be freed. On a similar vein, file corruption is a possible outcome. Could you please tell me what other things can possibly go wrong in this scenario?

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  • java question: Is it a method?

    - by Stefan
    Hello, I'm no Java guy, so I ask myself what this means: public Button(Light light) { this.light = light; } Is Button a method? I ask myself, because it takes an input parameter light. But if it was a method, why would it begin with a capital letter and has no return data type? Here comes the full example: public class Button { private Light light; public Button(Light light) { this.light = light; } public void press() { light.turnOn(); } } I know, this question is really trivial. However, I have nothing to do with Java and haven't found a description for the Button thing above. I'm just interested.

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  • where does the professional sheen of a GUI application realistically come from?

    - by JW
    I have been playing around with php-gtk recently and in the past I have experimented with Java to make GUI 'hello world' apps. However both these types of applications have had a bit of a clunky (almost childish) look and feel to them. I cannot deny that they are handy for making apps for in-house use (and I totally respect the amount of community effort that goes into these projects). But I would not necessarily be proud to sell it as a commercial application with a price tag of, say, £450 or £1,000. If I wanted to make an application that had the look and feel of, say, Firefox for Windows, or Adobe xyz, what GUI/language should I use? Is the 'professional sheen' or smart look and feel down to the designer or is it the case that, no matter how good a designer is, picking the right GUI framework is essential to get that look?

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  • C#: How to inherit constructors?

    - by Ian Boyd
    Imagine a base class with many constructors and a virtual method public class Foo { ... public Foo() {...} public Foo(int i) {...} ... public virtual void SomethingElse() {...} ... } and now I want to create a descendant class that overrides the virtual method: public class Bar : Foo { public override void SomethingElse() {...} } And another descendant that does some more stuff: public class Bah : Bar { public void DoMoreStuff() {...} } Do I really have to copy all constructors from Foo into Bar and Bah? And then if I change a constructor signature in Foo, do I have to update it in Bar and Bah? Is there no way to inherit constructors? Is there no way to encourage code reuse?

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  • Tips on designing a .NET API for future use with F#

    - by Drew Noakes
    I'm in the process of designing a .NET API to allow developers to create RoboCup agents for the 3D simulated soccer league. I'm pretty happy with how the API work with C# code, however I would like to use this project to improve my F# skill (which is currently based on reading rather than practice). So I would like to ask what kinds of things I should consider when designing an API that is to be consumed by both C# and F# code. Some points. I make fairly heavy use of matrix and vector math. These are currently immutable classes/structs. The API currently defines a few interfaces with the consumer implements (eg: IAgent), using instances of their implementations (eg: MyAgent) to construct other API classes (eg: new Client(myAgent)). The API fires events. The API exposes a few delegate types. The API includes several enums. I'd like to release a version of the API as soon as possible and don't want to make major changes to it later if I realise it's too difficult to work with from F#. Any advice is appreciated.

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  • Natural vs surrogate keys on support tables

    - by Bugeo
    I have read many articles about the battle between natural versus surrogate primary keys. I agree in the use of surrogate keys to identify records of tables whose contents are created by the user. But in the case of supporting tables what should I use? For example, in a hypothetical table "orderStates". If you use a natural key would have the following data: TABLE ORDERSTATES {ID: "NEW", NAME: "New"} {ID: "MANAGEMENT" NAME: "Management"} {ID: "SHIPPED" NAME: "Shipped"} If I use a surrogate key would have the following data: TABLE ORDERSTATES {ID: 1 CODE: "NEW", NAME: "New"} {ID: 2 CODE: "MANAGEMENT" NAME: "Management"} {ID: 3 CODE: "SHIPPED" NAME: "Shipped"} Now let's take an example: a user enters a new order. In the case in which use natural keys, in the code I can write this: newOrder.StateOrderId = "NEW"; With the surrogate keys instead every time I have an additional step. stateOrderId_NEW = .... I retrieve the id corresponding to the recod code "NEW" newOrder.StateOrderId = stateOrderId_NEW; The same will happen every time I have to move the order in a new status. So, in this case, what are the reason to chose one key type vs the other one?

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  • best option to create simple website mockup with navigation

    - by Buzzer
    I'm trying to put together a static html website with full navigation. In other words, I want the user to click some links and images and actually be taken to another page. I'm a developer so I know how to do this in frameworks like ASP.Net MVC and grails. However, for this particular case, I just want to quickly mock up the UI and provide simple navigation so I can do some user testing. Can anyone advice on how to do this? Thanks,

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  • Which source control paradigm and solution to embed in a custom editor application?

    - by Greg Harman
    I am building an application that manages a number of custom objects, which may be edited concurrently by multiple users (using different instances of the application). These objects have an underlying serialized representation, and my plan is to persist them (through my application UI) in an external source control system. Of course this implies that my application can check the current version of an object for updates, a merging interface for each object, etc. My question is what source control paradigm(s) and specific solution(s) to support and why. The way I (perhaps naively) see the source control world is three general paradigms: Single-repository, locked access (MS SourceSafe) Single-repository, concurrent access (CVS/SVN) Distributed (Mercurial, Git) I haven't heard of anyone using #1 for quite a number of years, so I am planning to disregard this case altogether (unless I get a compelling argument otherwise). However, I'm at a loss as to whether to support #2 or #3, and which specific implementations. I'm concerned that the use paradigms are subtly different enough that I can't adequately capture basic operations in a single UI. The last bit of information I should convey is that this application is intended to be deployed in a commercial setting, where a source control system may already be in use. I would prefer not to support more than one solution unless it's really a deal-breaker, so wide adoption in a corporate setting is a plus.

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  • Data Modeling Help - Do I add another table, change existing table's usage, or something else?

    - by StackOverflowNewbie
    Assume I have the following tables and relationships: Person - Id (PK) - Name A Person can have 0 or more pets: Pet - Id (PK) - PersonId (FK) - Name A person can have 0 or more attributes (e.g. age, height, weight): PersonAttribute _ Id (PK) - PersonId (FK) - Name - Value PROBLEM: I need to represent pet attributes, too. As it turns out, these pet attributes are, in most cases, identical to the attributes of a person (e.g. a pet can have an age, height, and weight too). How do I represent pet attributes? Do I create a PetAttribute table? PetAttribute Id (PK) PetId (FK) Name Value Do I change PersonAttribute to GenericAttribute and have 2 foreign keys in it - one connecting to Person, the other connecting to Pet? GenericAttribute Id (PK) PersonId (FK) PetId (FK) Name Value NOTE: if PersonId is set, then PetId is not set. If PetId is set, PersonId is not set. Do something else?

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  • How do I write this MySQL query?

    - by CT
    I am working on an Asset DB using a lamp stack. In this example consider the following 5 tables: asset, server, laptop, desktop, software All tables have a primary key of id, which is a unique asset id. Every object has all asset attributes and then depending on type of asset has additional attributes in the corresponding table. If the type is a server, desktop or laptop it also has items in the software table. Here are the table create statements: // connect to mysql server and database "asset_db" mysql_connect("localhost", "asset_db", "asset_db") or die(mysql_error()); mysql_select_db("asset_db") or die(mysql_error()); // create asset table mysql_query("CREATE TABLE asset( id VARCHAR(50) PRIMARY KEY, company VARCHAR(50), location VARCHAR(50), purchase_date VARCHAR(50), purchase_order VARCHAR(50), value VARCHAR(50), type VARCHAR(50), notes VARCHAR(200))") or die(mysql_error()); echo "Asset Table Created.</br />"; // create software table mysql_query("CREATE TABLE software( id VARCHAR(50) PRIMARY KEY, software VARCHAR(50), license VARCHAR(50))") or die(mysql_error()); echo "Software Table Created.</br />"; // create laptop table mysql_query("CREATE TABLE laptop( id VARCHAR(50) PRIMARY KEY, manufacturer VARCHAR(50), model VARCHAR(50), serial_number VARCHAR(50), esc VARCHAR(50), user VARCHAR(50), prev_user VARCHAR(50), warranty VARCHAR(50))") or die(mysql_error()); echo "Laptop Table Created.</br />"; // create desktop table mysql_query("CREATE TABLE desktop( id VARCHAR(50) PRIMARY KEY, manufacturer VARCHAR(50), model VARCHAR(50), serial_number VARCHAR(50), esc VARCHAR(50), user VARCHAR(50), prev_user VARCHAR(50), warranty VARCHAR(50))") or die(mysql_error()); echo "Desktop Table Created.</br />"; // create server table mysql_query("CREATE TABLE server( id VARCHAR(50) PRIMARY KEY, manufacturer VARCHAR(50), model VARCHAR(50), warranty VARCHAR(50))") or die(mysql_error()); echo "Server Table Created.</br />"; ?> How do I query the database so that if I search by id, I receive all related fields to that asset id? Thank you.

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  • Using inheritance and polymorphism to solve a common game problem

    - by Barry Brown
    I have two classes; let's call them Ogre and Wizard. (All fields are public to make the example easier to type in.) public class Ogre { int weight; int height; int axeLength; } public class Wizard { int age; int IQ; int height; } In each class I can create a method called, say, battle() that will determine who will win if an Ogre meets and Ogre or a Wizard meets a Wizard. Here's an example. If an Ogre meets an Ogre, the heavier one wins. But if the weight is the same, the one with the longer axe wins. public Ogre battle(Ogre o) { if (this.height > o.height) return this; else if (this.height < o.height) return o; else if (this.axeLength > o.axeLength) return this; else if (this.axeLength < o.axeLength) return o; else return this; // default case } We can make a similar method for Wizards. But what if a Wizard meets an Ogre? We could of course make a method for that, comparing, say, just the heights. public Wizard battle(Ogre o) { if (this.height > o.height) return this; else if (this.height < o.height) return o; else return this; } And we'd make a similar one for Ogres that meet Wizard. But things get out of hand if we have to add more character types to the program. This is where I get stuck. One obvious solution is to create a Character class with the common traits. Ogre and Wizard inherit from the Character and extend it to include the other traits that define each one. public class Character { int height; public Character battle(Character c) { if (this.height > c.height) return this; else if (this.height < c.height) return c; else return this; } } Is there a better way to organize the classes? I've looked at the strategy pattern and the mediator pattern, but I'm not sure how either of them (if any) could help here. My goal is to reach some kind of common battle method, so that if an Ogre meets an Ogre it uses the Ogre-vs-Ogre battle, but if an Ogre meets a Wizard, it uses a more generic one. Further, what if the characters that meet share no common traits? How can we decide who wins a battle?

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  • Two Tables Serving as one Model in Rails

    - by matsko
    Is is possible in rails to setup on model which is dependant on a join from two tables? This would mean that for the the model record to be found/updated/destroyed there would need to be both records in both database tables linked together in a join. The model would just be all the columns of both tables wrapped together which may then be used for the forms and so on. This way when the model gets created/updated it is just one form variable hash that gets applied to the model? Is this possible in Rails 2 or 3?

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  • Meaning of Primary Key to Microsoft SQL Server 2008

    - by usr
    What meaning does the concept of a primary key have to the database engine of SQL Server? I don't mean the clustered/nonclustered index created on the "ID" column, i mean the constraint object "primary key". Does it matter if it exists or not? Alternatives: alter table add primary key clustered alter table create clustered index Does it make a difference?

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  • Truly declarative language?

    - by gjvdkamp
    Hi all, Does anyone know of a truly declarative language? The behaviour I'm looking for is kind of what Excel does, where I can define variables and formulas, and have the formula's result change when the input changes (without having set the answer again myself) The behaviour I'm looking for is best shown with this pseudo code: X = 10 // define and assign two variables Y = 20; Z = X + Y // declare a formula that uses these two variables X = 50 // change one of the input variables ?Z // asking for Z should now give 70 (50 + 20) I've tried this in a lot of languages like F#, python, matlab etc, but every time i try this they come up with 30 instead of 70. Wich is correct from an imperative point of view, but i'm looking for a more declerative behaviour if you know what i mean. And this is just a very simple calculation. When things get more difficult it should handle stuff like recursion and memoization automagically. The code below would obviously work in C# but it's just so much code for the job, i'm looking for something a bit more to the point without all that 'technical noise' class BlaBla{ public int X {get;set;} // this used to be even worse before 3.0 public int Y {get;set;} public int Z {get{return X + Y;}} } static void main(){ BlaBla bla = new BlaBla(); bla.X = 10; bla.Y = 20; // can't define anything here bla.X = 50; // bit pointless here but I'll do it anyway. Console.Writeline(bla.Z);// 70, hurray! } This just seems like so much code, curly braces and semicolons that add nothing. Is there a language/ application (apart from Exel) that does this? Maybe I'm no doing it right in the mentioned langauges, or I've completely missed an app that does just this. I prototyped a language/ application that does this (along with some other stuff) and am thinking of productizing it. I just can't believe it's not there yet. Don't want to waste my time. Thanks in advance, Gert-Jan

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  • OOP - Handling Automated Instances of a Class - PHP

    - by dscher
    This is a topic that, as a beginner to PHP and programming, sort of perplexes me. I'm building a stockmarket website and want users to add their own stocks. I can clearly see the benefit of having each stock be a class instance with all the methods of a class. What I am stumped on is the best way to give that instance a name when I instantiate it. If I have: class Stock() { ....doing stuff..... } what is the best way to give my instances of it a name. Obviously I can write: $newStock = new Stock(); $newStock.getPrice(); or whatever, but if a user adds a stock via the app, where can the name of that instance come from? I guess that there is little harm in always creating a new child with $newStock = new Stock() and then storing that to the DB which leads me to my next question! What would be the best way to retrieve 20 user stocks(for example) into instances of class Stock()? Do I need to instantiate 20 new instances of class Stock() every time the user logs in or is there something I'm missing? I hope someone answers this and more important hope a bunch of people answer this and it somehow helps someone else who is having a hard time wrapping their head around what probably leads to a really elegant solution. Thanks guys!

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  • Clean up upon the kill signal

    - by Begui
    How do you handle clean up when the program receives a kill signal? For instance, there is an application I connect to that wants any third party app (my app) to send a finish command. What is the best say to send that finish command when my app has been destroyed with a kill -9?

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  • Is the set of data always normalized in one form or the other in Databases

    - by manugupt1
    Suppose I have a set of data, given the data and the relation schemas can I assume that the set of data is normalized in one form or the other. In my opinion raw data given, has to be normalized into some form. However a discussion with a friend has led to ask me this question here. To expound more on the question, I would say given a set of functional dependencies for a relation or table, is it guaranteed that the table would atleast be in 1NF if not others

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  • Perl classes like stuff

    - by user350571
    Hello, lovers of the camel. I'm new to perl and it's blessing stuff to imitate class like functionality made me feel strange I even had to go to the bathroom. Now, please tell me: what do you don't like, find wrong or strange with this code: sub Person { my $age = shift || 15; return { printAge => sub { print "Age -> $age\n"; }, changeAge => sub { $age = shift } } } my $p = Person(); my $p2 = Person(27); $p->{printAge}->(); $p->{changeAge}->(30); $p->{printAge}->(); $p2->{printAge}->(); I'm going to walk my dog, hope to get responses when I'm back. Thanks in advance. Cheers. Be back soon. Thanks again.

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  • Singleton Pattern combine with a Decorator

    - by Mike
    Attached is a classic Decorator pattern. My question is how would you modify the below code so that you can wrap zero or one of each topping on to the Pizza Right now I can have a Pepporini - Sausage -- Pepporini -- Pizza class driving the total cost up to $10, charging twice for Pepporini. I don't think I want to use the Chain of Responsibility pattern as order does not matter and not all toppings are used? Thank you namespace PizzaDecorator { public interface IPizza { double CalculateCost(); } public class Pizza: IPizza { public Pizza() { } public double CalculateCost() { return 8.00; } } public abstract class Topping : IPizza { protected IPizza _pizzaItem; public Topping(IPizza pizzaItem) { this._pizzaItem = pizzaItem; } public abstract double CalculateCost(); } public class Pepporini : Topping { public Pepporini(IPizza pizzaItem) : base(pizzaItem) { } public override double CalculateCost() { return this._pizzaItem.CalculateCost() + 0.50; } } public class Sausage : Topping { public Sausage(IPizza pizzaItem) : base(pizzaItem) { } public override double CalculateCost() { return this._pizzaItem.CalculateCost() + 1.00; } } public class Onions : Topping { public Onions(IPizza pizzaItem) : base(pizzaItem) { } public override double CalculateCost() { return this._pizzaItem.CalculateCost() + .25; } } }

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  • Binary Search Tree for specific intent

    - by Luís Guilherme
    We all know there are plenty of self-balancing binary search trees (BST), being the most famous the Red-Black and the AVL. It might be useful to take a look at AA-trees and scapegoat trees too. I want to do deletions insertions and searches, like any other BST. However, it will be common to delete all values in a given range, or deleting whole subtrees. So: I want to insert, search, remove values in O(log n) (balanced tree). I would like to delete a subtree, keeping the whole tree balanced, in O(log n) (worst-case or amortized) It might be useful to delete several values in a row, before balancing the tree I will most often insert 2 values at once, however this is not a rule (just a tip in case there is a tree data structure that takes this into account) Is there a variant of AVL or RB that helps me on this? Scapegoat-trees look more like this, but would also need some changes, anyone who has got experience on them can share some thougts? More precisely, which balancing procedure and/or removal procedure would help me keep this actions time-efficient?

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  • CSS box around box technique

    - by webzide
    Dear Experts, I was trying to make an CSS division box with content in it as well as a border around it. Instead of using the box-border technique, I was trying out a new box to box technique instead. <html> <head> <style type="text/css"> #outer{ height: 20px; width: 20px; background-color:#233D78; } #inner{ height:18px; width: 18px; background-color: #FFF; font-size: 1em; text-align:center; font-family:'Bookman Old Style', serif; padding: 0px; margin-top: 1px; margin-right:auto; margin-left:auto; margin-bottom:1px; vertical-align:middle; } </style> </head> <body> <div id="outer"><div id="inner">TEXT</div></div> </body> </html> Somehow the borders are just not showing up right with FireFox. I tried everything. Setting up the Paddings of both boxes, margin, and messing around with the width. TO be honest, it took me around 30min to do this and I still can't get it right :( I know that a way to achieve the same result would be setting up a border around just one box. But I just wanna learn this box around box background-color technique. THanks in advance

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  • Database Modelling - Conceptually different entities but with near identical fields

    - by Andrew Shepherd
    Suppose you have two sets of conceptual entities: MarketPriceDataSet which has multiple ForwardPriceEntries PoolPriceForecastDataSet which has multiple PoolPriceForecastEntry Both different child objects have near identical fields: ForwardPriceEntry has MarketPriceDataSetId (foreign key to parent table) StartDate EndDate SimulationItemId ForwardPrice PoolPriceForecastEntry has PoolPriceForecastDataSetId (foreign key to parent table) StartDate EndDate SimulationItemId ForecastPoolPrice If I modelled them as separate tables, the only difference would be the foreign key, and the name of the price field. There has been a debate as to whether the two near identical tables should be merged into one. Options I've thought of to model this is: Just keep them as two independent, separate tables Have both sets in the one table with an additional "type" field, and a parent_id equalling a foreign key to either parent table. This would sacrifice referential integrity checks. Have both sets in the one table with an additional "type" field, and create a complicated sequence of joining tables to maintain referential integrity. What do you think I should do, and why?

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