Search Results

Search found 5895 results on 236 pages for 'cake pattern'.

Page 17/236 | < Previous Page | 13 14 15 16 17 18 19 20 21 22 23 24  | Next Page >

  • Entity and pattern validation vs DB constraint

    - by Joerg
    When it comes to performance: What is the better way to validate the user input? If you think about a phone number and you only want numbers in the database, but it could begin with a 0, so you will use varchar: Is it better to check it via the entity model like this: @Size(min = 10, max = 12) @Digits(fraction = 0, integer = 12) @Column(name = "phone_number") private String phoneNumber; Or is it better to use on the database side a CHECK (and no checking in the entity model) for the same feature?

    Read the article

  • MVC Design Pattern to Combine Multiple Models for use

    - by roverred
    In my design, I have multiple models and each model has a controller. I need to use all the models to process some operation. Most examples I see are pretty simple with 1 view, 1 controller, and 1 model. How would you get all these models together? Only ways I can think of are 1) Have a top-level controller which has a reference to every controller. Those controllers will have a getter/setter function for their model. Does this violate MVC because every controller should have a model? 2) Have an Intermediate class to combine every model into a one model. Then you create a controller for that new super model. Do you know of any better ideas? Thanks.

    Read the article

  • "Collection Wrapper" pattern - is this common?

    - by Prog
    A different question of mine had to do with encapsulating member data structures inside classes. In order to understand this question better please read that question and look at the approach discussed. One of the guys who answered that question said that the approach is good, but if I understood him correctly - he said that there should be a class existing just for the purpose of wrapping the collection, instead of an ordinary class offering a number of public methods just to access the member collection. For example, instead of this: class SomeClass{ // downright exposing the concrete collection. Things[] someCollection; // other stuff omitted Thing[] getCollection(){return someCollection;} } Or this: class SomeClass{ // encapsulating the collection, but inflating the class' public interface. Thing[] someCollection; // class functionality omitted. public Thing getThing(int index){ return someCollection[index]; } public int getSize(){ return someCollection.length; } public void setThing(int index, Thing thing){ someCollection[index] = thing; } public void removeThing(int index){ someCollection[index] = null; } } We'll have this: // encapsulating the collection - in a different class, dedicated to this. class SomeClass{ CollectionWrapper someCollection; CollectionWrapper getCollection(){return someCollection;} } class CollectionWrapper{ Thing[] someCollection; public Thing getThing(int index){ return someCollection[index]; } public int getSize(){ return someCollection.length; } public void setThing(int index, Thing thing){ someCollection[index] = thing; } public void removeThing(int index){ someCollection[index] = null; } } This way, the inner data structure in SomeClass can change without affecting client code, and without forcing SomeClass to offer a lot of public methods just to access the inner collection. CollectionWrapper does this instead. E.g. if the collection changes from an array to a List, the internal implementation of CollectionWrapper changes, but client code stays the same. Also, the CollectionWrapper can hide certain things from the client code - from example, it can disallow mutation to the collection by not having the methods setThing and removeThing. This approach to decoupling client code from the concrete data structure seems IMHO pretty good. Is this approach common? What are it's downfalls? Is this used in practice?

    Read the article

  • Designing web-based plugin systems correctly so they don't waste as many resources?

    - by Xeoncross
    Many CMS systems which rely on third parties for much of their code often build "plugin" or "hooks" systems to make it easy for developers to modify the codebase's actions without editing the core files. This usually means an Observer or Event design pattern. However, when you look at systems like wordpress you see that on every page they load some kind of bootstrap file from each of the plugin's folders to see if that plugin will need to run that request. Its this poor design that causes systems like wordpress to spend many extra MB's of memory loading and parsing unneeded items each page. Are there alternative ways to do this? I'm looking for ideas in building my own. For example, Is there a way to load all this once and then cache the results so that your system knows how to lazy-load plugins? In other words, the system loads a configuration file that specifies all the events that plugin wishes to tie into and then saves it for future requests? If that also performs poorly, then perhaps there is a special file-structure that could be used to make educated guesses about when certain plugins are unneeded to fullfil the request. Any ideas? If anyone wants an example of the "plugin" concept you can find one here.

    Read the article

  • How do I implement repository pattern and unit of work when dealing with multiple data stores?

    - by Jason
    I have a unique situation where I am building a DDD based system that needs to access both Active Directory and a SQL database as persistence. Initially this wasnt a problem because our design was setup where we had a unit of work that looked like this: public interface IUnitOfWork { void BeginTransaction() void Commit() } and our repositories looked like this: public interface IRepository<T> { T GetByID() void Save(T entity) void Delete(T entity) } In this setup our load and save would handle the mapping between both data stores because we wrote it ourselves. The unit of work would handle transactions and would contain the Linq To SQL data context that the repositories would use for persistence. The active directory part was handled by a domain service implemented in infrastructure and consumed by the repositories in each Save() method. Save() was responsible with interacting with the data context to do all the database operations. Now we are trying to adapt it to entity framework and take advantage of POCO. Ideally we would not need the Save() method because the domain objects are being tracked by the object context and we would just need to add a Save() method on the unit of work to have the object context save the changes, and a way to register new objects with the context. The new proposed design looks more like this: public interface IUnitOfWork { void BeginTransaction() void Save() void Commit() } public interface IRepository<T> { T GetByID() void Add(T entity) void Delete(T entity) } This solves the data access problem with entity framework, but does not solve the problem with our active directory integration. Before, it was in the Save() method on the repository, but now it has no home. The unit of work knows nothing other than the entity framework data context. Where should this logic go? I argue this design only works if you only have one data store using entity framework. Any ideas how to best approach this issue? Where should I put this logic?

    Read the article

  • nHibernate session - Using repository pattern in Web, windows, wcf etc...

    - by alex
    I recently posted a question which was answered by Bryan Watts, regarding generic repository for nHibernate. I'm trying to design my data access to allow various facets - from ASP.net, WCF and Windows Forms / Windows services. I'm a bit confused re: session management etc.. How would I handle this? I've been checking out code such as: http://membranecms.googlecode.com/svn/ and questions such as: http://stackoverflow.com/questions/1207833/nhibernate-linq-session-management But what do i do if i don't just do things in a web based environment..? Do i need to create different repositories for each client? Or do i pass in the ISession into the (for example) UserRepository constructor..? ... as a side note I'm using nHibernate.Linq Also using fluent nHibernate to config my mapping

    Read the article

  • How do you code up a pattern matching block in scala?

    - by egervari
    How do you code a function that takes in a block of code that contains case statements? For instance, in my block of code, I don't want to code a match or a default case... looking something like this myApi { case Whatever() => // code for case 1 case SomethingElse() => // code for case 2 } And inside of my myApi(), it'll actually do the matches. Help?

    Read the article

  • How do you code up a pattern matching code block in scala?

    - by egervari
    How do you code a function that takes in a block of code as a parameter that contains case statements? For instance, in my block of code, I don't want to do a match or a default case explicitly. I am looking something like this myApi { case Whatever() => // code for case 1 case SomethingElse() => // code for case 2 } And inside of my myApi(), it'll actually execute the code block and do the matches. Help?

    Read the article

  • Good case for a Null Object Pattern? (Provide some service with a mailservice)

    - by fireeyedboy
    For a website I'm working on, I made an Media Service object that I use in the front end, as well as in the backend (CMS). This Media Service object manipulates media in a local repository (DB); it provides the ability to upload/embed video's and upload images. In other words, website visitors are able to do this in the front end, but administrators of the site are also able to do this in the backend. I'ld like this service to mail the administrators when a visitor has uploaded/embedded a new medium in the frontend, but refrain from mailing them when they upload/embed a medium themself in the backend. So I started wondering whether this is a good case for passing a null object, that mimicks the mail funcionality, to the Media Service in the backend. I thought this might come in handy when they decide the backend needs to have implemented mail functionality as well. In simplified terms I'ld like to do something like this: Frontend: $mediaService = new MediaService( new MediaRepository(), new StandardMailService() ); Backend: $mediaService = new MediaService( new MediaRepository(), new NullMailService() ); How do you feel about this? Does this make sense? Or am I setting myself up for problems down the road?

    Read the article

  • ASP.NET MVC - How to Unit Test boundaries in the Repository pattern?

    - by JK
    Given a basic repository interface: public interface IPersonRepository { void AddPerson(Person person); List<Person> GetAllPeople(); } With a basic implementation: public class PersonRepository: IPersonRepository { public void AddPerson(Person person) { ObjectContext.AddObject(person); } public List<Person> GetAllPeople() { return ObjectSet.AsQueryable().ToList(); } } How can you unit test this in a meaningful way? Since it crosses the boundary and physically updates and reads from the database, thats not a unit test, its an integration test. Or is it wrong to want to unit test this in the first place? Should I only have integration tests on the repository? I've been googling the subject and blogs often say to make a stub that implements the IRepository: public class PersonRepositoryTestStub: IPersonRepository { private List<Person> people = new List<Person>(); public void AddPerson(Person person) { people.Add(person); } public List<Person> GetAllPeople() { return people; } } But that doesnt unit test PersonRepository, it tests the implementation of PersonRepositoryTestStub (not very helpful).

    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

  • 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

  • PRG Pattern and Sticky Forms

    - by Scott Christopherson
    I'm using the PRG pattern on a form of mine. I've never used this approach before and I'm trying to figure something out: Normally, I always just displayed the posted form again when there were validation errors and displayed POST values in the form (sticky form). However with the PRG pattern, the form is displayed after a redirect, so there aren't any POST values. So my question is, how can I implement the PRG pattern and still have sticky forms?

    Read the article

  • Ignore duplicates in regex pattern

    - by gAMBOOKa
    I have a regex pattern that searches for words in a text file. How do I ignore duplicates? For instance, take a look at this code $pattern = '/(lorem|ipsum|daboom|pahwal|ababaga)/i'; $num_found = preg_match_all( $pattern, $string, $matches ); echo "$num_found match(es) found!"; echo "Matched words: " . implode( ',', $matches[0] ); If I have more than one say lorem in the article, the output will be something like this 5 matches found! Matched words: daboom,lorem,lorem,lorem,lorem I want the pattern to only find the first occurrence, and ignore the rest, so the output should be: 2 matches found! Matched words: daboom,lorem

    Read the article

< Previous Page | 13 14 15 16 17 18 19 20 21 22 23 24  | Next Page >