Search Results

Search found 8962 results on 359 pages for 'abstract factory pattern'.

Page 227/359 | < Previous Page | 223 224 225 226 227 228 229 230 231 232 233 234  | Next Page >

• SQLite DB borked when opened on a different machine

  - by pruefsumme

  Hello, I'm using SQLite to store some data. The primary database is on a NAS (Debian Lenny, 2.6.15, armv4l) since the NAS runs a script which updates the data every day. A typical "select * from tableX" looks like this: 2010-12-28|20|62.09|25170.0 2010-12-28|21|49.28|23305.7 2010-12-28|22|48.51|22051.1 2010-12-28|23|47.17|21809.9 When I copy the DB to my main computer (Mac OS X) and run the same SQL query, the output is: 2010-12-28|20|1.08115035175016e-160|25170.0 2010-12-28|21|2.39343503830763e-259|-9.25596535779558e+61 2010-12-28|22|-1.02951149572792e-86|1.90359837597183e+185 2010-12-28|23|-1.10707273937033e-234|-2.35343828462275e-185 The 3rd and 4th column have the type REAL. Interesting fact: When the numbers are integer (i.e. they end with ".0"), there is no difference between the two databases. In all other cases, the differences are ... hm ... surprising? I can't seem to find a pattern. If someone's got a clue - please share!

  Read the article

• Magento: Why do controller action predispatch events not fire if the controller is rewritten?

  - by mattalexx

  Why do controller action predispatch events not fire if the controller is rewritten? Here is a snippet of store/app/code/core/Mage/Core/Controller/Varien/Action.php: abstract class Mage_Core_Controller_Varien_Action { // [...] public function preDispatch() { // [...] if ($this->_rewrite()) { return; // [What is the purpose if this?] } // [...] // [This is where my event needs to be firing, but this code never gets // executed because the controller is rewritten] Mage::dispatchEvent( 'controller_action_predispatch_'.$this->getFullActionName(), array('controller_action'=>$this) ); } // [...] } I don't know where to start fixing this problem. Anyone out there ever dealt with this before?

  Read the article

• C#: why Base class is allowed to implement an interface contract without inheriting from it?

  - by etarassov

  I've stumbled upon this "feature" of C# - the base class that implements interface methods does not have to derive from it. Example: public interface IContract { void Func(); } // Note that Base does **not** derive from IContract public abstract class Base { public void Func() { Console.WriteLine("Base.Func"); } } // Note that Derived does *not* provide implementation for IContract public class Derived : Base, IContract { } What happens is that Derived magically picks-up a public method Base.Func and decides that it will implement IContract.Func. What is the reason behind this magic? IMHO: this "quasi-implementation" feature is very-unintuitive and make code-inspection much harder. What do you think?

  Read the article

• How to get my first programming job.

  - by itsbunnies

  What is the best way to go about getting your very first programming job? I am currently going to college but have a few years before I graduate. I want to get out of my current "factory" job and into a computer related field as soon as possible. I found quite a few positions that I qualify for, but believe my pathetic resume has hurt me. My resume has a "skills" section where I list everything I am familiar with, but my employment section contains my first job (Super Wash, best car wash around!) and my current job (Assembling stuff that makes up various fans and motors). How do I get a company to give me a chance?

  Read the article

• c# Generic overloaded method dispatching ambiguous

  - by sebgod

  Hello, I just hit a situation where a method dispatch was ambiguous and wondered if anyone could explain on what basis the compiler (.NET 4.0.30319) chooses what overload to call interface IfaceA { } interface IfaceB<T> { void Add(IfaceA a); T Add(T t); } class ConcreteA : IfaceA { } class abstract BaseClassB<T> : IfaceB<T> { public virtual T Add(T t) { ... } public virtual void Add(IfaceA a) { ... } } class ConcreteB : BaseClassB<IfaceA> { // does not override one of the relevant methods } void code() { var concreteB = new ConcreteB(); // it will call void Add(IfaceA a) concreteB.Add(new ConcreteA()); } In any case, why does the compiler not warn me or even why does it compile? Thank you very much for any answers.

  Read the article

• Zend_Form and Liskov Substitution Principle

  - by blockhead

  A very common pattern I see (I'm picking on Zend Framework, only because I was dealing with it at the moment of this question), is something like this: class My_Form extends Zend_Form { public function init() { $this->addElement(); } } Zend_Form is not an abstract class, but is perfectly usable on its own. This seems to be "recommended" as place to "encapsulate" your forms into a nice class. Does this violate the Liskov Substitution Principle? Each subclass of Zend_Form will have a wildy different behavior than the base class. Would it be better to use composition for this, or am I totally misunderstanding this principle?

  Read the article

• Outlook Replies with Inline Comments

  - by BillN

  I have a user who uses Word as his e-mail editor. Often when replying to an e-mail, he'll insert his comments into the body of the original e-mail. Since he is using Word as the editor, these show as [User Name] Comment Text in a contrasting color. However, some users see the comments in their Outlook, and others do not. I've tried Selecting/DeSelecting Word as the e-mail editor on the recipients, and it does not seem to make a difference. We are using Exchange 2007 with Outlook 2003 and Outlook 2007 clients along with a few Entourage Clients. There does not seem to be a pattern related to which client is used, but Entourage seems to be more likely to have the problem. TIA, Bill

  Read the article

• Using enums or a set of classes when I know I have a finite set of different options?

  - by devoured elysium

  Let's say I have defined the following class: public abstract class Event { public DateTime Time { get; protected set; } protected Event(DateTime time) { Time = time; } } What would you prefer between this: public class AsleepEvent : Event { public AsleepEvent(DateTime time) : base(time) { } } public class AwakeEvent : Event { public AwakeEvent(DateTime time) : base(time) { } } and this: public enum StateEventType { NowAwake, NowAsleep } public class StateEvent : Event { protected StateEventType stateType; public MealEvent(DateTime time, StateEventType stateType) : base(time) { stateType = stateType; } } and why? I am generally more inclined to the first option, but I can't explain why. Is it totally the same or are any advantages in using one instead of the other? Maybe with the first method its easier to add more "states", altough in this case I am 100% sure I will only want two states: now awake, and now asleep (they signal the moments when one awakes and one falls asleep).

  Read the article

• Is there a concise way to create an InputSupplier for an InputStream in Google Guava?

  - by Fabian Steeg

  There are a few factory methods in Google Guava to create InputSuppliers, e.g. from a byte[]: ByteStreams.newInputStreamSupplier(bytes); Or from a File: Files.newInputStreamSupplier(file); Is there a similar way to to create an InputSupplier for a given InputStream? That is, a way that's more concise than an anonymous class: new InputSupplier<InputStream>() { public InputStream getInput() throws IOException { return inputStream; } }; Background: I'd like to use InputStreams with e.g. Files.copy(...) or ByteStreams.equal(...).

  Read the article

• Statsd, Graphite and graphs

  - by w00t

  I've setup Graphite and statsd and both are running well. I'm using the example-client.py from graphite/examples to measure load values and it's OK. I started doing tests with statsd and at first it seemed ok because it generated some graphs but now it doesn't look quite well. First, this is my storage-schema.conf: pattern = .* retentions = 10:2160,60:10080,600:262974 I'm using this command to send data to statsd: echo 'ssh.invalid_users:1|c'| nc -w 1 -u localhost 8126 it executes, I click Update Graph in the Graphite web interface, it generates a line, hit again Update and the line disappears. If I execute the previous command 5 times, the graph line will reach 2 and it will actually save it. Again running the same command two times, graph line reaches 2 and disappears. I can't find what I have misconfigured. The intended use is this: tail -n 0 -f /var/log/auth.log|grep --line-buffered "Invalid user" | while read line; do echo "ssh.invalid_users:1|c" | nc -w 1 -u localhost 8126; done

  Read the article

• Fluent NHibernate + multiple databases

  - by Pablote

  My project needs to handle three databases, that means three session factories. The thing is if i do something like this with fluent nhibernate: .Mappings(m = m.FluentMappings.AddFromAssembly(Assembly.GetExecutingAssembly())) the factories would pick up all the mappings, even the ones that correspond to another database I've seen that when using automapping you can do something like this, and filter by namespace: .Mappings(m = m.AutoMappings.Add(AutoMap.AssemblyOf().Where(t = t.Namespace == "Storefront.Entities"))) I havent found anything like this for fluent mappings, is it possible?? The only solutions I can think of are: either create separate assemblies for each db mapping classes or explicitly adding each of the entities to the factory configuration. I would prefer to avoid both, if possible. Thanks.

  Read the article

• Passing dependent objects to a parent constructor in Scala

  - by Nick Johnson

  Suppose I have the following class heirarchy: class A() class B(a:A) class C(b:B) class BaseClass(b:B, c:C) Now I want to implement a subclass of BaseClass, which is given an instance of A, and constructs instances of B and C, which it passes to its superclass constructor. If I could use arbitrary expressions, I'd do something like this: b = new B(a) c = new C(b) super(b, c) Because the second argument to the parent constructor depends on the value of the first argument, though, I can't see any way to do this, without using a factory function, or a gratuitous hack, such as : class IntermediateSubclass(b:B) extends BaseClass(b, new C(b)) class RealSubclass(a:A) extends IntermediateSubclass(new B(a)) Is there clean way to do this?

  Read the article

• Connect two daemons in python

  - by Simon

  What is the best way to connect two daemons in Python? I have daemon A and B. I'd like to receive data generated by B in A's module (maybe bidirectional). Both daemons support plugins, so I'd like to shut communication in plugins. What's the best and cross-platform way to do that? I know few mechanisms from low-level solutions - shared memory (C/C++), linux pipe, sockets (TCP/UDP), etc. and few high-level - queue (JMS, Rabbit), RPC. Both daemons should run on the same host, but obviously better approach is to abstract from connection type. What are typical solutions/libraries in python? I'm looking for an elegant and lightweight solution. I don't need external server, just two processes talking with each other. What should I use in python to do that?

  Read the article

• no ocijdbc10 in java.library.path

  - by B.Z.B

  Hey all, So I've been plagued by this issue, whenever I try to run my app in eclipse, I get this error. 2011-02-23 09:55:08,388 ERROR (com.xxxxx.services.factory.ServiceInvokerLocal:21) - java.lang.UnsatisfiedLinkError: no ocijdbc10 in java.library.path I've tried following the steps I found here with no luck. I've tried this on a XP VM as well as windows 7 (although in win 7 I get a different error, below) java.lang.UnsatisfiedLinkError: no ocijdbc9 in java.library.path I've made sure my oracle client was ok (by running TOAD) and I also re-added the classes12.jar / ojdbc14.jars to my WEB-INF/lib folder taken directly from my %ORACLE_HOME% folder (also re-added them to the lib path). I've also tried just adding the ojdbc14.jar without the classes12.jar. Any suggestions appreciated. In the XP VM I have my PATH variable set to C:\Program Files\Java\jdk1.6.0_24\bin;C:\ORACLE\product\10.2.0.1\BIN. I'm using Tomcat server 5.0

  Read the article

• Pure virtual destructor in interface

  - by ALOR

  Hello all. Here is my problem. I'm making C++ dll, which extensively relies on instance object exports. So i return my actual instances as a pointers to interface through some exported factory method. Interfaces i use are purely virtual, to avoid linking problame. So i need a pure virtual destructor too, and i implemented one (with empty body, as i googled it). All compiles perfectly well, except... I can't see, if the actual destructors are called or not - because when i added some std::cout << "hello destructor"; i never get to see it. I have some explicit "delete obj", that's not the problem. Am i missing something? Is there another way to delete my object through interface?

  Read the article

• Custom OData operation / customize EF model to hide join table in many-to-many relationship

  - by AC

  I've got a data model that has two tables with a join table for a many to many relationship & creating an OData service to expose the data for CRUD ops in a Silverlight app. What I'd like to do is abstract the join table from the service. I'm not sure if the best way to do this would be in the model (using EF in .NET3.5SP1) or if I should do it with a custom service operation. If I do it in the EF model (not sure how I'd do this), then the OOTB WCF Data Service stuff would make it easy to say [..]/Courses(1)/Modules ... otherwise I'd have to create a custom operation to do this. Is it possible to do this in the EF model and if so, how does that work?

  Read the article

• Is it possible to create nested classes in PHP as it is in C#?

  - by Edward Tanguay

  In C# you can have nested classes like this, which are useful if you have classes which do not have meaning outside the scope of one particular class, e.g. in a factory pattern: public abstract class BankAccount { private BankAccount() {} private sealed class SavingsAccount : BankAccount { ... } private sealed class CheckingAccount : BankAccount { ... } public BankAccount MakeSavingAccount() { ... } public BankAccount MakeCheckingAccount() { ... } } Is this possible in PHP? I've read that it was planned for PHP 5, then cancelled, then planned again, but can't find definitive info. Does anyone know how to create nested classes (classes within the scope of another class) as in the above C# example using PHP 5.3?

  Read the article

• How to whitelist a domain while blocking forgeries using that domain?

  - by QuantumMechanic

  How do you deal with the case of: wanting to whitelist a domain so that emails from it won't get eaten, but not having emails forged to appear to be from that domain get bogusly whitelisted whitelist_from_recvd looks promising, but then you have to know at least the TLD of every host that could send you mail from that domain. Often RandomBigCompany.com will outsource email to one or more sending companies (like Constant Contact and the like) in addition to using servers that reverse-resolve to something in its own domain. But it looks like whitelist_from_recvd can only map to one sending server pattern so that would be problematic. Is there a way to say something like "if email is from domain X, subtract N points from the spam score"? The idea would be that if the mail is legit, that -N will all but guarantee it isn't considered spam. But if it is spam, hopefully all the other failed tests will render it spam even with the -N being included.

  Read the article

• Creating a computer with pencil and paper [closed]

  - by Justian Meyer

  This concept has been brought to my attention before, but many people might know it from this popular comic here, where he uses stones instead of points on a paper. This concept is so abstract to me. A full-functioning computer that can manage algorithms, input, output, etc. without electricity? Surely, it's difficult to visualize because my definition of a computer is not exactly what the word sounds like COMPUTE-ER. Can someone help me bring the concept to light - the understanding, how to make one, etc? It seems like it'd be an interesting read, although I think I wouldn't be able to make it do anything. Many thanks in advance for responses. I've tried searching Google, but all I got were ways to diagram code and chart ideas. -.Justian.

  Read the article

• How can one describe a rock-paper-scissors relationship between 3 items?

  - by Madara Uchiha

  Let's say I have the following structure: abstract class Hand {} class Rock extends Hand {} class Paper extends Hand {} class Scissors extends Hand {} The goal is to make a function (or a method) Hand::compareHands(Hand $hand1, Hand $hand2), which would return the winning hand in a rock-paper-scissors match. That would be very easy with a bunch of ifs, but the point is to have a more robust structure, that's relying on polymorphism rather than on procedural code. P.S. this is done in actual production code, if someone is asking. This isn't some sort of challenge or homework. (It's not really rock-paper-scissors, but you get the point).

  Read the article

• Do best-practices say to restrict the usage of /var to sudoers?

  - by NewAlexandria

  I wrote a package, and would like to use /var to persist some data. The data I'm storing would perhaps even be thought of as an addition for /var/db. The pattern I observe is that files in /var/db, and the surrounds, are owned by root. The primary (intended) use of the package filters cron jobs - meaning you would need permissions to edit the crontab. Should I presume a sudo install of the package? Should I have the package gracefully degrade to a /usr subdir, and if so then which one? If I 'opinionate' that any non-sudo install requires a configrc (with paths), where should the package look (presuming a shared-host environment) for that config file? Incidentally, this package is a ruby gem, and you can find it here.

  Read the article

• nginx errors: upstream timed out (110: Connection timed out)

  - by Sparsh Gupta

  Hi, I have a nginx server with 5 backend servers. We serve around 400-500 requests/second. I have started getting a large number of Upstream Timed out errors (110: Connection timed out) Error string in error.log looks like 2011/01/10 21:59:46 [error] 1153#0: *1699246778 upstream timed out (110: Connection timed out) while reading response header from upstream, client: {IP}, server: {domain}, request: "GET {URL} HTTP/1.1", upstream: "http://{backend_server}:80/{url}", host: "{domain}", referrer: "{referrer}" Any suggestions how to debug such errors. I am unable to find a munin plugin to keep a check on number of upstream errors. Sometime the number of errors per day is way too high and somedays its a more decent 3 digit number. A munin graph would probably help us finding out any pattern or correlation with anything else How can we make the number of such error as ZERO

  Read the article

• How to set order of appearance for fields when using Html.EditorFor in MVC 2?

  - by Anrie

  I have the following classes in my Model: public abstract class Entity : IEntity { [ScaffoldColumn(false)] public int Id { get; set; } [Required,StringLength(500)] public string Name { get; set; } } and public class Model : SortableEntity { [Required] public ModelType Type { get; set; } [ListRequired] public List<Producer> Producers { get; set; } public List<PrintArea> PrintAreas { get; set; } public List<Color> Colors { get; set; } } To display the "Model" class in the view I simply call Html.EditorFor(model=model), but the "Name" property of the base class is rendered last, which is not the desired behaviour. Is it possible to influenece on the order of displayed fields somehow?

  Read the article

• Questions about my program and Polymorphism

  - by Strobe_

  Ok, so basically I'm creating a program which allows the user to select a shape (triangle, square, circle) and then it takes in a int and calculates the boundary length and area. I have no problem doing this and have a program that's working perfectly. (https://gist.github.com/anonymous/c63a03c129560a7b7434 4 classes) But now I have to implement this with polymorphism concepts and I'm honestly struggling as to how to do it. I have a basic idea of what I want to do when it comes to inheritance Main | Shapes / | \ triangle circle square But I don't understand how I'm supposed to override when all the methods within the triangle/square/circle classes are unique, there are no "abstract" methods as such that I could inherit from the "Shapes" class. If somebody could make look quickly at the code I linked and suggest a way to do this it would be much appreciated. Sorry if I was bad at explaining this. Thanks.

  Read the article

• NHibernate: discriminator without common base class?

  - by joniba

  Is it possible to map two classes to the same property without them sharing a common base class? For example, a situation like this: class Rule { public virtual int SequenceNumber { get; set; } public virtual ICondition Condition { get; set; } } interface ICondition { } class ExpressionCondition : ICondition { public virtual string Expression { get; set; } } class ThresholdCondition : ICondition { public virtual int Threshold { get; set; } } I also cannot add some empty abstract class that both conditions inherit from because the two ICondition implementations exist in different domains that are not allowed to reference each other. (Please no responses telling me that this situation should not occur in the first place - I'm aware of it and it doesn't help me.)

  Read the article

< Previous Page | 223 224 225 226 227 228 229 230 231 232 233 234  | Next Page >