Search Results

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

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 31/359 | < Previous Page | 27 28 29 30 31 32 33 34 35 36 37 38  | Next Page >

  • Difference between Class Abstraction and Object Interfaces in PHP?

    - by Mark Tomlin
    What is the difference between a Class Abstraction and an Object Interfaces in PHP? I ask because, I don't really see the point to both of them, they both do the same thing! So, what are the advantages of disadvantages using both against one or the other? Class Abstraction: abstract class aClass { // Force extending class to define these methods abstract public function setVariable($name, $var); abstract public function getHtml($template); } Object Interface: interface iClass { // Force impementing class to define these methods public function setVariable($name, $var); public function getHtml($template); }

    Read the article

  • Question about decorator pattern and the abstract decorator class?

    - by es11
    This question was asked already here, but rather than answering the specific question, descriptions of how the decorator pattern works were given instead. I'd like to ask it again because the answer is not immediately evident to me just by reading how the decorator pattern works (I've read the wikipedia article and the section in the book Head First Design Patterns). Basically, I want to know why an abstract decorator class must be created which implements (or extends) some interface (or abstract class). Why can't all the new "decorated classes" simply implement (or extend) the base abstract object themselves (instead of extending the abstract decorator class)? To make this more concrete I'll use the example from the design patterns book dealing with coffee beverages: There is an abstract component class called Beverage Simple beverage types such as HouseBlend simply extend Beverage To decorate beverage, an abstract CondimentDecorator class is created which extends Beverage and has an instance of Beverage Say we want to add a "milk" condiment, a class Milk is created which extends CondimentDecorator I'd like to understand why we needed the CondimentDecorator class and why the class Milk couldn't have simply extended the Beverage class itself and been passed an instance of Beverage in its constructor. Hopefully this is clear...if not I'd simply like to know why is the abstract decorator class necessary for this pattern? Thanks. Edit: I tried to implement this, omitting the abstract decorator class, and it seems to still work. Is this abstract class present in all descriptions of this pattern simply because it provides a standard interface for all of the new decorated classes?

    Read the article

  • Is context inheritance, as shown by Head First Design Patterns' Duck example, irrelevant to strategy pattern?

    - by Korey Hinton
    In Head First Design Patterns it teaches the strategy pattern by using a Duck example where different subclasses of Duck can be assigned a particular behavior at runtime. From my understanding the purpose of the strategy pattern is to change an object's behavior at runtime. Emphasis on "an" meaning one. Could I further simplify this example by just having a Duck class (no derived classes)? Then when implementing one duck object it can be assigned different behaviors based on certain circumstances that aren't dependent on its own object type. For example: FlyBehavior changes based on the weather or QuackBehavior changes based on the time of day or how hungry a duck is. Would my example above constitute the strategy pattern as well? Is context inheritance (Duck) irrelevant to the strategy pattern or is that the reason for the strategy pattern? Here is the UML diagram from the Head First book:

    Read the article

  • Servlet mapping url patterns

    - by Scobal
    I have the following urls that need mapping to two different servlets. Can anyone suggest a working url-pattern please? vehlocsearch-ws: /ws/vehlocsearch/vehlocsearch /ws/vehavailrate/vehavailratevehlocsearch /ws/vehavailrate/vehavailratevehlocsearch.wsdl vehavailrate-ws: /ws/vehavailrate/vehavailrate /ws/vehavailrate/vehavailratevehavailrate /ws/vehavailrate/vehavailratevehavailrate.wsdl So far I have this, which feels right, but isn't: <servlet-mapping> <servlet-name>vehlocsearch-ws</servlet-name> <url-pattern>*.vehlocsearch*</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>vehavailrate-ws</servlet-name> <url-pattern>*.vehavailrate*</url-pattern> </servlet-mapping> Note: I have no control over the incoming urls

    Read the article

  • iPhone core data problem : referenceData64 only defined for abstract class

    - by occe
    I have an application that downloads/parses a big XML file and store the information using core data (approx. 4000 objects (entities)). The XML is loaded/parsed in a different thread, which has its own NSManagedObjectContext. When trying to save the entities to the persistent store, I sometimes get the following error (about 20%) 2010-03-03 23:41:42.802 xxx[7487:4203] Exception in XML saving 2010-03-03 23:41:42.802 xxx[7487:4203] Description: * -_referenceData64 only defined for abstract class. Define -[NSTemporaryObjectID_default _referenceData64]! 2010-03-03 23:41:42.803 xxx[7487:4203] Name: NSInvalidArgumentException 2010-03-03 23:41:42.804 xxx[7487:4203] UserInfo: (null) 2010-03-03 23:41:42.805 xxx[7487:4203] Reason: * -_referenceData64 only defined for abstract class. Define -[NSTemporaryObjectID_default _referenceData64]! I have a simple integer to keep track of the entities the application creates compared to the insertedObjects property in the NSManagedObjectContext before saving, and when I get the error, these numbers do not match, insertedObjects in the NSManagedObjectContext is missing about 10 entities. I do not know how I should continue to investigate this problem, anyone has any idea how to fix this? Thanks /oscar

    Read the article

  • Retrieving the COM class factory for component error while generating word document

    - by TheDPQ
    Hello, I am trying to edit a word document from VB.NET using for the most part this code: How to automate Word from Visual Basic .NET to create a new document http://support.microsoft.com/kb/316383 It works fine on my machine but when i publish to the server i get the following error. Retrieving the COM class factory for component with CLSID {000209FF-0000-0000-C000-000000000046} failed due to the following error: 80070005. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.UnauthorizedAccessException: Retrieving the COM class factory for component with CLSID {000209FF-0000-0000-C000-000000000046} failed due to the following error: 80070005. The actual error happens when i try to just create a word application object Dim oWord As New Word.Application Using Visual Studio 2008 and VB.NET 3.5. I made a reference to the "Microsoft Word 10.0 Object Library" and i see Interop.Word.dll file in the bin directory. Using MS Office 2003 on development machine and Windows Server 2003 Still fairly new to .NET and don't have much knowledge about window server, but "UnauthorizedAccessException" sounds like a permission issue. I'm wondering if someone could point me in the right direction on what i might need to do to give my little application access to use word. Thank you so much for your time.

    Read the article

  • Mapping interface or abstract class component

    - by Yann Trevin
    Please consider the following simple use case: public class Foo { public virtual int Id { get; protected set; } public virtual IBar Bar { get; set; } } public interface IBar { string Text { get; set; } } public class Bar : IBar { public virtual string Text { get; set; } } And the fluent-nhibernate map class: public class FooMap : ClassMap<Foo> { public FooMap() { Id(x => x.Id); Component(x => x.Bar, m => { m.Map(x => x.Text); }); } } While running any query with configuration, I get the following exception: NHibernate.InstantiationException: "Cannot instantiate abstract class or interface: NHMappingTest.IBar" It seems that NHibernate tries to instantiate an IBar object instead of the Bar concrete class. How to let Fluent-NHibernate know which concrete class to instantiate when the property returns an interface or an abstract base class? EDIT: Explicitly specify the type of component by writing Component<Bar> (as suggested by Sly) has no effect and causes the same exception to occur. EDIT2: Thanks to vedklyv and Paul Batum: such a mapping should be soon is now possible.

    Read the article

  • PLKs and Web Service Software Factory

    - by Nix
    We found a bug in Web Service Software Factory a description can be found here. There has been no updates on it so we decided to download the code and fix it ourself. Very simple bug and we patched it with maybe 3 lines of code. However* we have now tried to repackage it and use it and are finding that this is seemingly an impossible process. Can someone please explain to me the process of PLKs? I have read all about them but still don't understand what is really required to distribute a VS package. I was able to get it to load and run using a PLK obtained from here, but i am assuming that you have to be a partner to get a functional PLK that will be recognized on other peoples systems? Every time i try and install this on a different computer I get a "Package Load Failure". Is the reason I am getting errors because I am not using a partner key? Is there any other way around this? For instance is there any way we can have an "internal" VS package that we can distribute? Edit Files I had to change to get it to work. First run devenv PostInstall.proj Generate your plks and replace ##Package PLK## (.resx files) --Just note that package version is not the class name but is "Web Service Software Factory: Modeling Edition" -- And you need to remove the new lines from the key ProductDefinitionRegistryFragment.wxi line 1252(update version to whatever version you used in plk) Uncomment all // [VSShell::ProvideLoadKey("Standard", Constant in .tt files.

    Read the article

  • Using Scala structural types with abstract types

    - by Joshua Hartman
    I'm trying to define a structural type defining anything that has an "add" method (for instance, a java collection or a java map). Using this, I want to define a few higher order functions that operate on a certain collection object GenericTypes { type GenericCollection[T] = { def add(value: T): java.lang.Boolean} } import GenericTypes._ trait HigherOrderFunctions[T, CollectionType[X] <: GenericCollection[X]] { def map[V](fn: (T) => V): CollectionType[V] .... } class RichJList[T](list: List[T]) extends HigherOrderFunctions[T, java.util.List] This does not compile with the following error error: Parameter type in structural refinement may not refer to abstract type defined outside that same refinement I tried removing the parameter on GenericCollection and putting it on the method: object GenericTypes { type GenericCollection = { def add[T](value: T): java.lang.Boolean} } import GenericTypes._ trait HigherOrderFunctions[T, CollectionType[X] <: GenericCollection] class RichJList[T](list: List[T]) extends HigherOrderFunctions[T, java.util.List] but I get another error: error: type arguments [T,java.util.List] do not conform to trait HigherOrderFunctions's type parameter bounds [T,CollectionType[X] <: org.scala_tools.javautils.j2s.GenericTypes.GenericCollection] Can anyone give me some advice on how to use structural typing with abstract typed parameters in Scala? Or how to achieve what I'm looking to accomplish? Thanks so much!

    Read the article

  • Nested factory methods in Objective-C

    - by StephenT
    What's the best way to handle memory management with nested factory methods, such as in the following example? @implementation MyClass + (MyClass *) SpecialCase1 { return [MyClass myClassWithArg:1]; } + (MyClass *) SpecialCase2 { return [MyClass myClassWithArg:2]; } + (MyClass *) myClassWithArg:(int)arg { MyClass *instance = [[[MyClass alloc] initWithArg:arg] autorelease]; return instance; } - (id) initWithArg:(int)arg { self = [super init]; if (nil != self) { self.arg = arg; } return self; } @end The problem here (I think) is that the autorelease pool is flushed before the SpecialCaseN methods return to their callers. Hence, the ultimate caller of SpecialCaseN can't rely on the result having been retained. (I get "[MyClass copyWithZone:]: unrecognized selector sent to instance 0x100110250" on trying to assign the result of [MyClass SpecialCase1] to a property on another object.) The reason for wanting the SpecialCaseN factory methods is that in my actual project, there are multiple parameters required to initialize the instance and I have a pre-defined list of "model" instances that I'd like to be able to create easily. I'm sure there's a better approach than this.

    Read the article

  • Problem using Lazy<T> from within a generic abstract class

    - by James Black
    I have a generic class that all my DAO classes derive from, which is defined below. I also have a base class for all my entities, but that is not generic. The method GetIdOrSave is going to be a different type than how I defined SabaAbstractDAO, as I am trying to get the primary key to fulfill the foreign key relationships, so this function goes out to either get the primary key or save the entity and then get the primary key. The last code snippet has a solution on how it will work if I get rid of the generic part, so I think this can be solved by using variance, but I can't figure out how to write an interface that will compile. public abstract class SabaAbstractDAO<T> { ... public K GetIdOrSave<K>(K item, Lazy<SabaAbstractDAO<BaseModel>> lazyitemdao) where K : BaseModel { if (item != null && item.Id.IsNull()) { var itemdao = lazyitemdao.Value; item.Id = itemdao.retrieveID(item); if (item.Id.IsNull()) { return itemdao.SaveData(item); } } return item; } } I am getting this error, when I try to compile: Argument 2: cannot convert from 'System.Lazy<ORNL.HRD.LMS.Dao.SabaCourseDAO>' to 'System.Lazy<ORNL.HRD.LMS.Dao.SabaAbstractDAO<ORNL.HRD.LMS.Models.BaseModel>>' I am trying to call it this way: GetIdOrSave(input.OfferingTemplate, new Lazy<SabaCourseDAO>( () => { return new SabaCourseDAO() { Dao = Dao }; }) ); If I change the definition to this, it works. public K GetIdOrSave<K>(K item, Lazy<SabaCourseDAO> lazyitemdao) where K : BaseModel { So, how can I get this to compile using variance (if needed) and generics, so I can have a very general method that will only work with BaseModel and AbstractDAO<BaseModel>? I expect I should only need to make the change in the method and perhaps abstract class definition, the usage should be fine.

    Read the article

  • Improve this generic abstract class

    - by Keivan
    I have the following abstract class design, I was wondering if anyone can suggest any improvements in terms of stronger enforcement of our requirements or simplifying implementing of the ControllerBase. //Dependency Provider base public abstract class ControllerBase<TContract, TType> where TType : TContract, class { public static TContract Instance { get { return ComponentFactory.GetComponent<TContract, TType>(); } } public TContract GetComponent<TContract, TType>() where TType : TContract, class { component = (TType)Activator.CreateInstance(typeof(TType), true); RegisterComponentInstance<TContract>(component); } } //Contract public interface IController { void DoThing(); } //Actual Class Logic public class Controller: ControllerBase<IController,Controller> { public void DoThing(); //internal constructor internal Controller(){} } //Usage public static void Main() { Controller.Instance.DoThing(); } The following facts should always be true, TType should always implement TContract (Enforced using a generic constraint) TContract must be an interface (Can't find a way to enforce it) TType shouldn't have public constructor, just an internal one, is there any way to Enforce that using ControllerBase? TType must be an concrete class (Didn't include New() as a generic constrain since the constructors should be marked as Internal)

    Read the article

  • Jersey, JAXB and getting an objectextending an abstract class as a parameter

    - by krajol
    I want to get an object as a parameter of a POST request. I got an abstract superclass that is called Promotion and subclasses Product and Percent. Here's how I try to get a request: @POST @Consumes(MediaType.APPLICATION_XML) @Produces(MediaType.APPLICATION_XML) @Path("promotion/") public Promotion createPromotion(Promotion promotion) { Product p = (Product) promotion; System.out.println(p.getPriceAfter()); return promotion; } and here's how I use JAXB in classes' definitions: @XmlRootElement(name="promotion") @XmlSeeAlso({Product.class,Percent.class}) public abstract class Promotion { //body } @XmlRootElement(name="promotion") public class Product extends Promotion { //body } @XmlRootElement(name="promotion") public class Percent extends Promotion { //body } So the problem now is when I send a POST request with a body like this: <promotion> <priceBefore>34.5</priceBefore> <marked>false</marked> <distance>44</distance> </promotion> and I try to cast it to Product (as in this case, fields 'marked' and 'distance' are from Promotion class and 'priceBefore' is from Product class) I get an Exception: java.lang.ClassCastException: Percent cannot be cast to Product. It seems like Percent is chosen as a 'default' subclass. Why is that and how can I get an object that is a Product?

    Read the article

  • interface variables are final and static by default and methods are public and abstract

    - by sap
    The question is why it's been decided to have variable as final and static and methods as public and abstract by default. Is there any particular reason for making them implicit,variable as final and static and methods as public and abstract. Why they are not allowing static method but allowing static variable? We have interface to have feature of multiple inheritance in Java and to avoid diamond problem. But how it solves diamond problem,since it does not allow static methods. In the following program, both interfaces have method with the same name..but while implementing only one we implement...is this how diamond problem is solved? interface testInt{ int m = 0; void testMethod(); } interface testInt1{ int m = 10; void testMethod(); } public class interfaceCheck implements testInt, testInt1{ public void testMethod(){ System . out . println ( "m is"+ testInt.m ); System . out . println ( "Hi World!" ); } }

    Read the article

  • Reset DRAC to factory defaults

    - by yakatz
    I put a DRAC that has not been used in a long time into a PowerEdge 1750 running CentOS 5.8. Because we run our DRACs on a separate network, we don't change the password from the default (root/calvin), but evidently someone changed this one. I tried the regular command line reset (racadm racresetcfg), but I get the following error: ERROR: Unable to perform requested operation. If the operation attempted was to configure DRAC, possible reason may be that Local Configuration using RACADM is disabled. This implies to me that racadm is able to communicate, but there is a setting on the DRAC that is preventing it from working. I was not able to find any references to this error in any Dell documentation. Has anyone seen this problem and/or know what I can do about it? (The DRAC is useless is I can't log in to it.)

    Read the article

  • Format Factory not working for mov files

    - by LanguaFlash
    I have attempted multiple destination formats with no success. I am using Format Factor 2.30. I drag and drop a .mov file into FF, select all to mpg (or any format) then click Start. It thinks for a couple seconds and then jumps to 100%. When I open the file I get no sound or picture from the video. These mov files were created with a Canon SX10 camera. (It is my brother's camera so I'm not sure of the model.) Any suggestions? TMPGEnc is able to convert the files with the QTReader plug in so the video isn't corrupted or something. Thanks. Jeff

    Read the article

  • Reset Windows system to factory defaults

    - by carlosz
    A friend just bought a netbook (HP mini 110) with Windows XP but it was the one used for testing in the store (the last one on storage) so it's somewhat filled with stuff from people testing the machine. How should I go about restoring the system to a ? As a first step I'm going to create a new User account and delete the old one (from the store). How do we change the name It's registered to? What other things should I take in account?

    Read the article

  • Restoring factory recovery partition (samsung)

    - by user974896
    I have upgraded the HDD in a Samsung laptop and would like to restore the "Press F4 for recovery" partition. My new disk has three partitions, System, Windows, and Recovery. I did a dd of the recovery partition from the old HDD to the new. I also set the diag flag on the new HDD. F4 recovery still is not working. tldr: I mapped my new disk like my old disk with the exception of exact sizes. I did the recover partition from old to new via livecd. F4 recovery does not work

    Read the article

  • Pass variable to regular expression pattern string in jquery

    - by phil
    Is that possible to pass variable into regular expression pattern string in jquery ( or javascript)? For example, I want to validate a zip code input field every time while user type in a character by passing variable i to the regular expression pattern. How to do it right? $('#zip').keyup( function(){ var i=$('#zip').val().length for ( i; i<=5; i++){ var pattern=/^[0-9]{i}$/; if ( !pattern.test( $('#zip').val() ) ) {$('#zip_error').css('display','inline');} else {$('#zip_error').css('display','none');} } })

    Read the article

  • java.util.regex.Pattern matching the beginning of a String

    - by Pierre
    Hi all, Is it possible to know if a stream/string contains an input that could match a regular expression. For example String input="AA"; Pattern pat=Pattern.compile("AAAAAB"); Matcher matcher=pat.matcher(input); //<-- something here returning true ? or String input="BB"; Pattern pat=Pattern.compile("AAAAAB"); Matcher matcher=pat.matcher(input); //<-- something here returning false ? Thanks

    Read the article

  • How does the following regex pattern work?

    - by zSysop
    Hi all, I'm horrible with regex but i'm trying to figure out how an import function works and i came across this regex pattern. Maybe one of you can help me understand how it works. string pattern = @"^""(?<code>.*)"",""(?<last_name>.*)"",""(?<first_name>.*)"",""(?<address>.*)"",""(?<city>.*)"",""(?<state>.*)"",""(?<zip>.*)""$"; Regex re = new Regex(pattern); Match ma = re.Match(_sReader.ReadLine().Trim()); Thanks

    Read the article

  • Finding a pattern within a string variable in C#

    - by lo3
    Ok i'm working on a project for a 200 level C# course, we are required to create a heads or tails project. Basically the project is setup so that the computer will guess randomly up to 5 times, but on the sixth time it will look into the playersGuessHistory variable setup as a string to see if it can find a match for a pattern of 4 entires, if there is a pattern found the computer will guess the next character after the pattern EX: [HHTT]H [HHTTH]H HHTT being the pattern then the computer would guess H for the next turn. My only problem is that i'm having difficulty setting up the project so that it will look through the playersguesshistory and find the patterns and guess the next character in the history. Any suggestions?

    Read the article

  • php replace a pattern

    - by Hulk
    Suppose in a file there is a pattern as sumthing.c: and asdfg.c: and many more.. with *.c: pattern How to replace this with the text yourinput and save the file using php The pattern is *.c thanks..

    Read the article

  • Best practice for DAO pattern ?

    - by Tony
    I've seen a lot of codes use a service-dao pattern , I don't know the origin of this pattern . It force the front layer call service , then delegates some of the service task to dao. I want to ask : Does DAO layer do purely data access related task ? What about exception encapsulation ? Is there other pattern can be used to replace this ?

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 27 28 29 30 31 32 33 34 35 36 37 38  | Next Page >