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  • NHibernate stored procedure problem

    - by Calvin
    I'm having a hard time trying to get my stored procedure works with NHibernate. The data returned from the SP does not correspond to any database table. This is my mapping file: <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="DomainModel" namespace="DomainModel.Entities"> <sql-query name="DoSomething"> <return class="SomeClass"> <return-property name="ID" column="ID"/> </return> exec [dbo].[sp_doSomething] </sql-query> </hibernate-mapping> Here is my domain class: namespace DomainModel.Entities { public class SomeClass { public SomeClass() { } public virtual Guid ID { get; set; } } } When I run the code, it fails with Exception Details: NHibernate.HibernateException: Errors in named queries: {DoSomething} at line 80 Line 78: config.Configure(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "NHibernate.config")); Line 79: Line 80: g_sessionFactory = config.BuildSessionFactory(); When I debug into NHibernate code, it seems that SomeClass is not added to the persister dictionary because there isn't a class mapping (only sql-query) defined in hbm.xml. And later on in CheckNamedQueries function, it is not able to find the persistor for SomeClass. I've checked all the obvious things (e.g. make hbm as an embedded resource) and my code isn't too much different from other samples I found on the web, but somehow I just can't get it working. Any idea how I can resolve this issue?

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  • Binder and variadic template ends up in a segmentation fault

    - by phlipsy
    I wrote the following program #include <iostream> template<typename C, typename Res, typename... Args> class bind_class_t { private: Res (C::*f)(Args...); C *c; public: bind_class_t(Res (C::*f)(Args...), C* c) : f(f), c(c) { } Res operator() (Args... args) { return (c->*f)(args...); } }; template<typename C, typename Res, typename... Args> bind_class_t<C, Res, Args...> bind_class(Res (C::*f)(Args...), C* c) { return bind_class<C, Res, Args...>(f, c); } class test { public: int add(int x, int y) { return x + y; } }; int main() { test t; // bind_class_t<test, int, int, int> b(&test::add, &t); bind_class_t<test, int, int, int> b = bind_class(&test::add, &t); std::cout << b(1, 2) << std::endl; return 0; } compiled it with gcc 4.3.3 and got a segmentation fault. After spending some time with gdb and this program it seems to me that the addresses of the function and the class are mixed up and a call of the data address of the class isn't allowed. Moreover if I use the commented line instead everything works fine. Can anyone else reproduce this behavior and/or explain me what's going wrong here?

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  • belongs_to with multiple models

    - by julie p
    Hi there! I am a Rails noob and have a question. I have a feed aggregator that is organized by this general concept: Feed Category (books, electronics, etc) Feed Site Section (home page, books page, etc) Feed (the feed itself) Feed Entry So: class Category < ActiveRecord::Base has_many :feeds has_many :feed_entries, :through => :feeds, :limit => 5 validates_presence_of :name attr_accessible :name, :id end class Section < ActiveRecord::Base has_many :feeds has_many :feed_entries, :through => :feeds, :limit => 5 attr_accessible :name, :id end class Feed < ActiveRecord::Base belongs_to :categories belongs_to :sections has_many :feed_entries validates_presence_of :name, :feed_url attr_accessible :name, :feed_url, :category_id, :section_id end class FeedEntry < ActiveRecord::Base belongs_to :feed belongs_to :category belongs_to :section validates_presence_of :title, :url end Make sense? Now, in my index page, I want to basically say... If you are in the Category Books, on the Home Page Section, give me the feed entries grouped by Feed... In my controller: def index @section = Section.find_by_name("Home Page") @books = Category.find_by_name("Books") end In my view: <%= render :partial => 'feed_list', :locals => {:feed_group => @books.feeds} -%> This partial will spit out the markup for each feed entry in the @books collection of Feeds. Now what I need to do is somehow combine the @books with the @section... I tried this: <%= render :partial => 'feed_list', :locals => {:feed_group => @books.feeds(:section_id => @section.id)} -%> But it isn't limiting by the section ID. I've confirmed the section ID by using the same code in the console... Make sense? Any advice? Thanks!

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  • css block links and images

    - by Andrew Heath
    Given this html: <div class="nation"> <a href="library.php?type=nation&amp;id=America"> <div class="nation-image"> <img src="nations/America.png" alt="snip" /> </div> <h3>America</h3> </a> </div> the following CSS results in the entire <div class="nation"> becoming a clickable block link: .nation {float: left; text-align: center; width: 189px;} .nation img {width: 160px; margin: 10px 0 0 0; border: 1px solid #16160C;} but if I make the following single addition: .nation {float: left; text-align: center; width: 189px;} .nation-image {height: 138px;} .nation img {width: 160px; margin: 10px 0 0 0; border: 1px solid #16160C;} to specify the height of <div class="nation-image"> then the image (and only the image) is no longer a link, but the rest of the div (margin around it, h3 etc) remain a block link... /I am teh confussd :-?

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  • Using Pylint with Django

    - by rcreswick
    I would very much like to integrate pylint into the build process for my python projects, but I have run into one show-stopper: One of the error types that I find extremely useful--:E1101: *%s %r has no %r member*--constantly reports errors when using common django fields, for example: E1101:125:get_user_tags: Class 'Tag' has no 'objects' member which is caused by this code: def get_user_tags(username): """ Gets all the tags that username has used. Returns a query set. """ return Tag.objects.filter( ## This line triggers the error. tagownership__users__username__exact=username).distinct() # Here is the Tag class, models.Model is provided by Django: class Tag(models.Model): """ Model for user-defined strings that help categorize Events on on a per-user basis. """ name = models.CharField(max_length=500, null=False, unique=True) def __unicode__(self): return self.name How can I tune Pylint to properly take fields such as objects into account? (I've also looked into the Django source, and I have been unable to find the implementation of objects, so I suspect it is not "just" a class field. On the other hand, I'm fairly new to python, so I may very well have overlooked something.) Edit: The only way I've found to tell pylint to not warn about these warnings is by blocking all errors of the type (E1101) which is not an acceptable solution, since that is (in my opinion) an extremely useful error. If there is another way, without augmenting the pylint source, please point me to specifics :) See here for a summary of the problems I've had with pychecker and pyflakes -- they've proven to be far to unstable for general use. (In pychecker's case, the crashes originated in the pychecker code -- not source it was loading/invoking.)

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  • JQuery Selector - Finding an img in a table

    - by CccTrash
    Cant seem to get the following to find the 'skull' button when the 'heart' button is clicked... Here is the JQuery... $(".voteup").click(function() { var id = $(this).attr("title"); var userID = $('[id$=HiddenFieldUserID]').val(); var ipAddress = $('[id$=HiddenFieldIPAddress]').val(); var skullButton = $(this).parent().siblings(".votedowntd").children("votedown"); registerUpVote("up", id, $(this), skullButton, userID, ipAddress); }); And the HTML... <table width="200px"> <td width="35px" class="votedowntd"> <img src='<%# (bool)Eval("skull") ? "images/skull.png" : "images/skull-bw.png" %>' alt="Vote Down" class="votedown" title='<%# Eval("entry.ID") %>' /> </td> <td width="130px" style="text-align: center;"> Num Votes Goes Here </td> <td width="35px" class="voteuptd"> <img src='<%# (bool)Eval("heart") ? "images/heart.png" : "images/heart-bw.png" %>' alt="Vote Up" class="voteup" title='<%# Eval("entry.ID") %>' /> </td> <tr> </tr> </table> So basically what I need to do is when one img is clicked, I need to find the other one. Why is what I have not working? Is there a better way to do this?

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  • calling background service from BroadcastReceiver....

    - by Shalini Singh
    Hi , i am trying to call a push notification background from BroadcastReceiver class.but my application is going to crash the code is given bellow public class AlarmReceiver extends BroadcastReceiver { Context ctx; static int count=1; @Override public void onReceive(Context context, Intent intent) { // TODO Auto-generated method stub //Toast.makeText(context, "working"+count, Toast.LENGTH_LONG).show(); count++; Log.e("broadcast***","receiver"); Intent myIntent=new Intent(context,NotifyService.class); myIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); context.startActivity(myIntent); } } * manifest entry:- <intent-filter> <action android:name="android.intent.action.BOOT_COMPLETED"/> </intent-filter> </receiver> Error: 05-24 15:17:00.042: ERROR/AndroidRuntime(424): Caused by: android.content.ActivityNotFoundException: Unable to find explicit activity class {com.android.alarm/com.android.alarm.NotifyService}; have you declared this activity in your AndroidManifest.xml? Please help me....

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  • Module based web project directory layout with git and symlinks

    - by karlthorwald
    I am planning my directory structure for a linux/apache/php web project like this: Only www.example.com/webroot/ will be exposed in apache www.example.com/ webroot/ index.php module1/ module2/ modules/ module1/ module1.class.php module1.js module2/ module2.class.php module2.css lib/ lib1/ lib1.class.php the modules/ and lib/ directory will only be in the php path. To make the css and js files visible in the webroot directory I am planning to use symlinks. webroot/ index.php module1/ module1.js (symlinked) module2/ module2.css (symlinked) I tried following these principles: layout by modules and libraries, not by file type and not by "public' or 'non public', index.php is an exception. This is for easier development. symlinking files that need to be public for the modules and libs to a public location, but still mirroring the layout. So the module structure is also visible in the resulting html code in the links, which might help development. How will git handle the symlinking of the single files correctly, is there something to consider? When it comes to images I will need to link directories, how to handle that with git? modules/ module3/ module3.class.php img/ img1.jpg img2.jpg img3.jpg They should be linked here: webroot/ module3/ img/ (symlinked ?) So this is a git and symlink question. But I would be interested to hear comments about the php layout, maybe you want to use the comment function for this.

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  • Using Sub-Types And Return Types in Scala to Process a Generic Object Into a Specific One

    - by pr1001
    I think this is about covariance but I'm weak on the topic... I have a generic Event class used for things like database persistance, let's say like this: class Event( subject: Long, verb: String, directobject: Option[Long], indirectobject: Option[Long], timestamp: Long) { def getSubject = subject def getVerb = verb def getDirectObject = directobject def getIndirectObject = indirectobject def getTimestamp = timestamp } However, I have lots of different event verbs and I want to use pattern matching and such with these different event types, so I will create some corresponding case classes: trait EventCC case class Login(user: Long, timestamp: Long) extends EventCC case class Follow( follower: Long, followee: Long, timestamp: Long ) extends EventCC Now, the question is, how can I easily convert generic Events to the specific case classes. This is my first stab at it: def event2CC[T <: EventCC](event: Event): T = event.getVerb match { case "login" => Login(event.getSubject, event.getTimestamp) case "follow" => Follow( event.getSubject, event.getDirectObject.getOrElse(0), event.getTimestamp ) // ... } Unfortunately, this is wrong. <console>:11: error: type mismatch; found : Login required: T case "login" => Login(event.getSubject, event.getTimestamp) ^ <console>:12: error: type mismatch; found : Follow required: T case "follow" => Follow(event.getSubject, event.getDirectObject.getOrElse(0), event.getTimestamp) Could someone with greater type-fu than me explain if, 1) if what I want to do is possible (or reasonable, for that matter), and 2) if so, how to fix event2CC. Thanks!

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  • How can i add list data in my object?

    - by Phsika
    Below codes run perfectly but i want to re generate simply static void YeniMethodListele() { Calisan calisan = new Calisan(){ ID=1, Ad="yusuf", SoyAd="karatoprak"}; List<Calisan> myList = new List<Calisan>(); myList.Add(calisan); MyCalisan myCalisan = new MyCalisan() { list = myList }; //myCalisan.list.Add(calisan); foreach (Calisan item in myCalisan.list) { Console.WriteLine(item.Ad.ToString()); } } } public class Calisan { public int ID { get; set; } public string Ad { get; set; } public string SoyAd { get; set; } } public class MyCalisan { public List<Calisan> list { get; set; } public MyCalisan() { list = new List<Calisan>(); } } static void YeniMethodListele() { Calisan calisan = new Calisan(){ ID=1, Ad="yusuf", SoyAd="karatoprak"}; MyCalisan myCalisan = new MyCalisan(); myCalisan.list.Add(calisan); foreach (Calisan item in myCalisan.list) { Console.WriteLine(item.Ad.ToString()); } } } public class Calisan { public int ID { get; set; } public string Ad { get; set; } public string SoyAd { get; set; } } public class MyCalisan { public List<Calisan> list { get; set; } public MyCalisan() { list = new List<Calisan>(); } }

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  • Absolutely positioned div on right causing scrollbar when the left doesn't

    - by Michael Snyder
    I'm trying to "flank" a centered div with some design elements that are absolutely positioned outside the main div's width. I'm getting a scroll bar due to the element on the right, but not the element on the left (IE6/7/8, Chrome, Firefox). How can I get rid of that horizontal scrollbar? <html> <head> <style type="text/css"> html, body { height: 100%; width: 100%; margin: 0; } body { text-align: center; } .wrapper { margin: 0 auto; position: relative; width: 960px; z-index: 0; } .main { background: #900; height: 700px; } .right, .left { position: absolute; height: 100px; width: 100px; } .right { background: #090; top: 0px; left: 960px; z-index: 1; } .left { background: #009; top: 0px; left: -100px; z-index: 1; } </style> </head> <body> <div class="wrapper"> <div class="main"></div> <div class="left"></div> <div class="right"></div> </div> </body> </html>

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  • error C3662: override specifier 'new' only allowed on member functions of managed classes

    - by William
    Okay, so I'm trying to override a function in a parent class, and getting some errors. here's a test case #include <iostream> using namespace std; class A{ public: int aba; void printAba(); }; class B: public A{ public: void printAba() new; }; void A::printAba(){ cout << "aba1" << endl; } void B::printAba() new{ cout << "aba2" << endl; } int main(){ A a = B(); a.printAba(); return 0; } And here's the errors I'm getting: Error 1 error C3662: 'B::printAba' : override specifier 'new' only allowed on member functions of managed classes c:\users\test\test\test.cpp 12 test Error 2 error C2723: 'B::printAba' : 'new' storage-class specifier illegal on function definition c:\users\test\test\test.cpp 19 test How the heck do I do this?

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  • Cannot edit values of DataGridView bound to a BindingList

    - by m_oLogin
    Hello community, I have trouble editing a databound bindinglist. Let me illustrate it with the following: Say I have the Person class: public Class Person{ private string m_firstname; private string m_lastname; public string FirstName{get;set;} public string LastName{get;set;} public Person{ ... } } I then have a containing class called Population: public class Population{ private BindingList<Person> m_lstPerson = new BindingList<Person>(); private string m_countryName; public BindingList<Person> ListPerson{get; set;} public string CountryName { get; set; } } I then have on one form a first datagridview with DataSource = m_lstPopulation (BindingList). The binding works like a charm when working with the Population objects. When I double click, it opens up a dialog form showing the object details. One tab in the details holds a datagridview bound to that population's ListPerson. The second datagridview displays fine. However, I cannot edit or add cells in this datagridview. None of the columns is set to read-only. In fact, both datagridview have just about the same parameters. What am I missing? It seems that a lock has been placed on the Population object so that its inner fields cannot be edited... Please advise. Thanks.

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  • Jquery: Display element relative to another

    - by namtax
    Hi I am trying to display a drop down list using jquery everytime a user clicks on a particular formfield... At the moment the HTML is as stands // Form field to enter the time an event starts <div> <label for="eventTime"> Event Time </label> <input type = "text" name="eventTime" id="eventTime" class="time"> </label> </div> // Form field to enter the time an event finishes <div> <label for="eventEnd"> Event Ends</label> <input type = "text" name="eventEnds" id="eventEnds" class="time"> </label> </div> And the Jquery looks like so // Display Time Picker $('.time').click(function(){ var thisTime = $(this); var timePicker = '<ul class="timePicker">' timePicker += '<li>10.00am</li>' timePicker += '<li>11.00am</li>' timePicker += '<li>12.00am</li>' timePicker += '</ul>' $('.timePicker').hide().insertAfter(thisTime); //show the menu directly over the placeholder var pos = thisTime.offset(); $(".timePicker").attr({ top: pos.top left: pos.left }); $(".timePicker").show(); }); However, when I click on one the form fields with class time, the timePicker drop down appears, but it always appears in the same location, not next to the form field as I would like. Any ideas? Thanks

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  • C# reflection, cloning

    - by Enriquev
    Say I have this class Myclass that contains this method: public class MyClass { public int MyProperty { get; set; } public int MySecondProperty { get; set; } public MyOtherClass subClass { get; set; } public object clone<T>(object original, T emptyObj) { FieldInfo[] fis = this.GetType().GetFields(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic); object tempMyClass = Activator.CreateInstance(typeof(T)); foreach (FieldInfo fi in fis) { if (fi.FieldType.Namespace != original.GetType().Namespace) fi.SetValue(tempMyClass, fi.GetValue(original)); else fi.SetValue(tempMyClass, this.clone(fi.GetValue(original), fi.GetValue(original))); } return tempMyClass; } } Then this class: public class MyOtherClass { public int MyProperty777 { get; set; } } when I do this: MyClass a = new MyClass { MyProperty = 1, MySecondProperty = 2, subClass = new MyOtherClass() { MyProperty777 = -1 } }; MyClass b = a.clone(a, a) as MyClass; how come on the second call to clone, T is of type object and not of type MyOtherClass

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  • Java generic Comparable where subclasses can't compare to eachother

    - by dege
    public abstract class MyAbs implements Comparable<MyAbs> This would work but then I would be able to compare class A and B with each other if they both extend MyAbs. What I want to accomplish however is the exact opposite. So does anyone know a way to get the generic type to be the own class? Seemed like such a simple thing at first... Edit: To explain it a little further with an example. Say you have an abstract class animals, then you extend it with Dogs and ants. I wouldn't want to compare ants with Dogs but I however would want to compare one dog with another. The dog might have a variable saying what color it is and that is what I want to use in the compareTo method. However when it comes to ants I would rather want to compare ant's size than their color. Hope that clears it up. Could possibly be a design flaw however.

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  • Improving field get and set performance with ASM or Javassist

    - by ng
    I would like to avoid reflection in an open source project I am developing. Here I have classes like the following. public class PurchaseOrder { @Property private Customer customer; @Property private String name; } I scan for the @Property annotation to determine what I can set and get from the PurchaseOrder reflectively. There are many such classes all using java.lang.reflect.Field.get() and java.lang.reflect.Field.set(). Ideally I would like to generate for each property an invoker like the following. public interface PropertyAccessor<S, V> { public void set(S source, V value); public V get(S source); } Now when I scan the class I can create a static inner class of PurchaseOrder like so. static class customer_Field implements PropertyAccessor<PurchaseOrder, Customer> { public void set(PurchaseOrder order, Customer customer) { order.customer = customer; } public Customer get(PurchaseOrder order) { return order.customer; } } With these I totally avoid the cost of reflection. I can now set and get from my instances with native performance. Can anyone tell me how I would do this. A code example would be great. I have searched the net for a good example but can find nothing like this. The ASM and Javasist examples are pretty poor also. The key here is that I have an interface that I can pass around. So I can have various implementations, perhaps one with Java Reflection as a default, one with ASM, and one with Javassist? Any help would be greatly appreciated.

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  • FluentValidation + s#arp

    - by csetzkorn
    Hi, Did someone implement something like this: http://www.jeremyskinner.co.uk/2010/02/22/using-fluentvalidation-with-an-ioc-container/ in s#arp? Thanks. Christian PS: Hi, I have made a start in using FluentValidation in S#arp. I have implemented a Validator factory: public class ResolveType { private static IWindsorContainer _windsorContainer; public static void Initialize(IWindsorContainer windsorContainer) { _windsorContainer = windsorContainer; } public static object Of(Type type) { return _windsorContainer.Resolve(type); } } public class CastleWindsorValidatorFactory : ValidatorFactoryBase { public override IValidator CreateInstance(Type validatorType) { return ResolveType.Of(validatorType) as IValidator; } } I think I will use services which can be used by the controllers etc.: public class UserValidator : AbstractValidator { private readonly IUserRepository UserRepository; public UserValidator(IUserRepository UserRepository) { Check.Require(UserRepository != null, "UserRepository may not be null"); this.UserRepository = UserRepository; RuleFor(user => user.Email).NotEmpty(); RuleFor(user => user.FirstName).NotEmpty(); RuleFor(user => user.LastName).NotEmpty(); } } public interface IUserService { User CreateUser(User User); } public class UserService : IUserService { private readonly IUserRepository UserRepository; private readonly UserValidator UserValidator; public UserService ( IUserRepository UserRepository ) { Check.Require(UserRepository != null, "UserRepository may not be null"); this.UserRepository = UserRepository; this.UserValidator = new UserValidator(UserRepository); } public User CreateUser(User User) { UserValidator.Validate(User); ... } } Instead of putting concrete validators in the service, I would like to use the above factory somehow. Where do I register it and how in s#arp (Global.asax)? I believe s#arp is geared towards the nhibernator validator. How do I deregister it? Thanks. Best wishes, Christian

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  • What are the hibernate annotations used to persist a value typed Map with an enumerated type as a ke

    - by Jason Novak
    I am having trouble getting the right hibernate annotations to use on a value typed Map with an enumerated class as a key. Here is a simplified (and extremely contrived) example. public class Thing { public String id; public Letter startLetter; public Map<Letter,Double> letterCounts = new HashMap<Letter, Double>(); } public enum Letter { A, B, C, D } Here are my current annotations on Thing @Entity public class Thing { @Id public String id; @Enumerated(EnumType.STRING) public Letter startLetter; @CollectionOfElements @JoinTable(name = "Thing_letterFrequencies", joinColumns = @JoinColumn(name = "thingId")) @MapKey(columns = @Column(name = "letter", nullable = false)) @Column(name = "count") public Map<Letter,Double> letterCounts = new HashMap<Letter, Double>(); } Hibernate generates the following DDL to create the tables for my MySql database create table Thing (id varchar(255) not null, startLetter varchar(255), primary key (id)) type=InnoDB; create table Thing_letterFrequencies (thingId varchar(255) not null, count double precision, letter tinyblob not null, primary key (thingId, letter)) type=InnoDB; Notice that hibernate tries to define letter (my map key) as a tinyblob, however it defines startLetter as a varchar(255) even though both are of the enumerated type Letter. When I try to create the tables I see the following error BLOB/TEXT column 'letter' used in key specification without a key length I googled this error and it appears that MySql has issues when you try to make a tinyblob column part of a primary key, which is what hibernate needs to do with the Thing_letterFrequencies table. So I would rather have letter mapped to a varchar(255) the way startLetter is. Unfortunately, I've been fussing with the MapKey annotation for a while now and haven't been able to make this work. I've also tried @MapKeyManyToMany(targetEntity=Product.class) without success. Can anyone tell me what are the correct annotations for my letterCounts map so that hibernate will treat the letterCounts map key the same way it does startLetter?

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  • jQuery: hard time to get <embed> element

    - by Patrick
    hi, how can I get the embed element with jQuery ? (I spent enough time trying with "children(), find(), last() jquery functions). This is my code. Until here it works, I would like to get the second children (embed). $('div.filefield-file').each(function(index) { console.log($(this).children()); }); </script> This is HTML code: Scheduling Video <div class="field-item even"> <div class="filefield-file clear-block"><div class="filefield-icon field-icon-video-x-flv"><img class="field-icon-video-x-flv" alt="video/x-flv icon" src="http://localhost/drupal/sites/all/modules/filefield/icons/protocons/16x16/mimetypes/video-x-generic.png"></div><div style="background-color: rgb(255, 255, 255); width: 400px;"><embed style="display: block;" src="/drupal/videoPlayer.swf?file=http://localhost/drupal/sites/default/files/files/projects/Project3/videos/screenshot.flv" type="application/x-shockwave-flash" pluginspage="http://www.adobe.com/go/getflashplayer" bgcolor="#ffffff" allowfullscreen="true" autoplay="true" flashvars="file=http://localhost/drupal/sites/default/files/files/projects/Project3/videos/screenshot.flv" height="400" width="400"><div>screenshot.flv</div></div></div> </div>

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  • Why is creating a ring buffer shared by different processes so hard (in C++), what I am doing wrong?

    - by recipriversexclusion
    I am being especially dense about this but it seems I'm missing an important, basic point or something, since what I want to do should be common: I need to create a fixed-size ring buffer object from a manager process (Process M). This object has write() and read() methods to write/read from the buffer. The read/write methods will be called by independent processes (Process R and W) I have implemented the buffer, SharedBuffer<T&>, it allocates buffer slots in SHM using boost::interprocess and works perfectly within a single process. I have read the answers to this question and that one on SO, as well as asked my own, but I'm still in the dark about how to have different processes access methods from a common object. The Boost doc has an example of creating a vector in SHM, which is very similar to what I want, but I want to instantiate my own class. My current options are: Use placement new, as suggested by Charles B. to my question; however, he cautions that it's not a good idea to put non-POD objects in SHM. But my class needs the read/write methods, how can I handle those? Add an allocator to my class definition, e.g. have SharedBuffer<T&, Alloc> and proceed similarly to the vector example given in boost. This sounds really complicated. Change SharedBuffer to a POD class, i.e. get rid of all the methods. But then how to synchronize reading and writing between processes? What am I missing? Fixed-length ring buffers are very common, so either this problem has a solution or else I'm doing something wrong.

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  • Join Query Not Working

    - by John
    Hello, I am using three MySQl tables: comment commentid loginid submissionid comment datecommented login loginid username password email actcode disabled activated created points submission submissionid loginid title url displayurl datesubmitted In these three tables, the "loginid" correspond. I would like to pull the top 10 loginids based on the number of "submissionid"s. I would like to display them in a 3-column HTML table that shows the "username" in the first column, the number of "submissionid"s in the second column, and the number of "commentid"s in the third column. I tried using the query below but it did not work. Any idea why not? Thanks in advance, John $sqlStr = "SELECT l.username ,l.loginid ,c.commentid ,count(s.commentid) countComments ,c.comment ,c.datecommented ,s.submissionid ,count(s.submissionid) countSubmissions ,s.title ,s.url ,s.displayurl ,s.datesubmitted FROM comment AS c INNER JOIN login AS l ON c.loginid = l.loginid INNER JOIN submission AS s ON c.loginid = s.loginid GROUP BY c.loginid ORDER BY countSubmissions DESC LIMIT 10"; $result = mysql_query($sqlStr); $arr = array(); echo "<table class=\"samplesrec1\">"; while ($row = mysql_fetch_array($result)) { echo '<tr>'; echo '<td class="sitename1"><a href="http://www...com/.../members/index.php?profile='.$row["username"].'">'.stripslashes($row["username"]).'</a></td>'; echo '</tr>'; echo '<td class="sitename1">'.stripslashes($row["countSubmissions"]).'</td>'; echo '</tr>'; echo '</tr>'; echo '<td class="sitename1">'.stripslashes($row["countComments"]).'</td>'; echo '</tr>'; } echo "</table>";

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  • proper use of volatile keyword

    - by luke
    I think i have a pretty good idea about the volatile keyword in java, but i'm thinking about re-factoring some code and i thought it would be a good idea to use it. i have a class that is basically working as a DB Cache. it holds a bunch of objects that it has read from a database, serves requests for those objects, and then occasionally refreshes the database (based on a timeout). Heres the skeleton public class Cache { private HashMap mappings =....; private long last_update_time; private void loadMappingsFromDB() { //.... } private void checkLoad() { if(System.currentTimeMillis() - last_update_time > TIMEOUT) loadMappingsFromDB(); } public Data get(ID id) { checkLoad(); //.. look it up } } So the concern is that loadMappingsFromDB could be a high latency operation and thats not acceptable, So initially i thought that i could spin up a thread on cache startup and then just have it sleep and then update the cache in the background. But then i would need to synchronize my class (or the map). and then i would just be trading an occasional big pause for making every cache access slower. Then i thought why not use volatile i could define the map reference as volatile private volatile HashMap mappings =....; and then in get (or anywhere else that uses the mappings variable) i would just make a local copy of the reference: public Data get(ID id) { HashMap local = mappings; //.. look it up using local } and then the background thread would just load into a temp table and then swap the references in the class HashMap tmp; //load tmp from DB mappings = tmp;//swap variables forcing write barrier Does this approach make sense? and is it actually thread-safe?

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  • Invalid method declaration, return type required

    - by Brett Steen
    I am getting an error at public Rectangle(double width, double height){ saying that it's an invalid method declaration, return type required. I'm not sure how to fix it. These are also my instructions for my assignment: Write a super class encapsulating a rectangle. A rectangle has two attributes representing the width and the height of the rectangle. It has methods returning the perimeter and the area of the rectangle. This class has a subclass, encapsulating a parallelepiped, or box. A parallelepiped has a rectangle as its base, and another attribute, its length. It has two methods that calculate and return its area and volume. `public class Rectangle1 { private double width; private double height; public Rectangle1(){ } public Rectangle(double width, double height){ this.width = width; this.height = height; } public double getWidth(){ return width; } public void setWidth(double width) { this.width = width; } public double getHeight(){ return height; } public void setHeight(double height){ this.height = height; } public double getArea(){ return width * height; } public double getPerimeter(){ return 2 * (width + height); } } public class TestRectangle { public static void main(String[] args) { Rectangle1 rectangle = new Rectangle1(2,4); System.out.println("\nA rectangle " + rectangle.toString()); System.out.println("The area is " + rectangle.getArea()); System.out.println("The perimeter is " + rectangle.getPerimeter()); } }`

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  • form layout in drupal from a module

    - by EricP
    I created my own module called "cssswitch". I'm trying to create my own html layout to display the admin form portion of the module. I understand how to use the hook_form_alter() to modify form elements, but I need to create the entire form layout to make some fields appear next to each other. It seems I need something like the way I have the frontend view of the node displayed with theme_cssswitch_display(), but for the admin part of the node. function cssswitch_form_alter(&$form, $form_state, $form_id) { switch($form_id) { case 'cssswitch_node_form': $form['hour_start']['#prefix'] = '<div class="start-box">'; $form['ampm_start']['#suffix'] = '</div>'; $form['ampm_start']['#attributes'] = array("style" => "border-width:2px;"); break; } } function cssswitch_theme() { return array( 'cssswitch_display' => array( 'arguments' => array('node'), ), ); } // to display the view of the node function theme_cssswitch_display($node) { $output = '<div class="cssswitch-cssfilename">Filename: '. check_plain($node->cssfilename). '</div>'; $output .= '<div class="cssswitch-time_start">Start: '. check_plain($node->hour_start). ':'.check_plain($node->minute_start).' '.check_plain($node->ampm_start).'</div>'; $output .= '<div class="cssswitch-time_end">End: '. check_plain($node->hour_end). ':'.check_plain($node->minute_end).' '.check_plain($node->ampm_end).'</div>'; return $output; } thanks for any help

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