Search Results

Search found 19541 results on 782 pages for 'event handling'.

Page 558/782 | < Previous Page | 554 555 556 557 558 559 560 561 562 563 564 565  | Next Page >

• What's the *right* way to handle a POST in FP?

  - by Malvolio

  I'm just getting started with FP and I'm using Scala, which may not be the best way, since I can always fall back to an imperative style if the going gets tough. I'd just rather not. I've got a very specific question that points to a broader lacuna in my understanding of FP. When a web application is processing a GET request, the user wants information that already exists on the web-site. The application only has to process and format the data in some way. The FB way is clear. When a web application is processing a POST request, the user wants change the information held on the site. True, the information is not typically held in application variables, it's in a database or a flat-file, but still, I get the feeling I'm not grokking FP properly. Is there a pattern for handling updates to static data in an FP language? My vague picture of this is that the application is handed the request and the then-current site state. The application does its thing and returns the new site-state. If the current site-state hasn't changed since the application started, the new state becomes the current state and the reply is sent back to the browser (this is my dim image of Clojure's style); if the current state has been changed (by another thread, well, something else happens ...

  Read the article

• Using delegate Types vs methods

  - by Grant Sutcliffe

  I see increasing use of the delegate types offered in the System namespace (Action; Predicate etc). As these are delegates, my understanding is that they should be used where we have traditionally used delegates in the past (asynchronous calls; starting threads, event handling etc). Is it just preference or is it considered practice to use these delegate types in scenarios such as the below; rather than using calls to methods we have declared (or anonymous methods): public void MyMethod { Action<string> action = delegate(string userName { try { XmlDocument profile = DataHelper.GetProfile(userName); UpdateMember(profile); } catch (Exception exception) { if (_log.IsErrorEnabled) _log.ErrorFormat(exception.Message); throw (exception); } }; GetUsers().ForEach(action); } At first, I found the code less intuitive to follow than using declared or anonymous methods. I am starting to code this way, and wonder what the view are in this regard. The example above is all within a method. Is this delegate overuse.

  Read the article

• Evaluating creation of GUI via file vs coding

  - by nevets1219

  I'm working on a utility that will be used to test the project I'm currently working on. What the utility will do is allow user to provide various inputs and it will sends out requests and provide the response as output. However, at this point the exact format (which input is required and what is optional) has yet to be fleshed out. In addition, coding in Swing is somewhat repetitive since the overall work is simple though this should be the safest route to go as I have more or less full control and every component can be tweaked as I want. I'm considering using a configuration file that's in XML to describe the GUI (at least one part of it) and then coding the event handling part (in addition to validation, etc). The GUI itself shouldn't be too complicated. For each type of request to make there's a tab for the request and within each tab are various inputs. There seems to be quite a few questions about this already but I'm not asking for a 3rd party library to do this. I'm looking to do this myself, since I don't think it'll be too overly complicated (hopefully). My main consideration for using this is re-usability (later on, for other projects) and for simplifying the GUI work. My question is: are there other pros/cons that I'm overlooking? Is it worth the (unknown) time to do this? I've built GUI in VB.NET and with Flex3 before.

  Read the article

• Laravel4: Checking many-to-many relationship attribute even when it does not exist

  - by Simo A.

  This is my first time with Laravel and also Stackoverflow... I am developing a simple course management system. The main objects are User and Course, with a many-to-many relationship between them. The pivot table has an additional attribute, participant_role, which defines whether the user is a student or an instructor within that particular course. class Course extends Eloquent { public function users() { return $this->belongsToMany('User')->withPivot('participant_role')->withTimestamps(); } } However, there is an additional role, system admin, which can be defined on the User object. And this brings me mucho headache. In my blade view I have the following: @if ($course->pivot->participant_role == 'instructor') { // do something here... } This works fine when the user has been assigned to that particular $course and there is an entry for this user-course combination in the pivot table. However, the problem is the system administrator, who also should be able to access course details. The if-clause above gives Trying to get property of non-object error, apparently because there is no entry in the pivot table for system administrator (as the role is defined within the User object). I could probably solve the problem by using some off-the-shelf bundle for handling role-based permissions. Or I could (but don't want to) do something like this with two internal if-clauses: if (!empty($course->pivot)) { if ($course->pivot->participant_role == 'instructor') { // do something... } } Other options (suggested in partially similar entries in Stackoverflow) would include 1) reading all the pivot table entries to an array, and use in_array to check if a role exists, or even 2) SQL left join to do this on database level. However, ultimately I am looking for a compact one-line solution? Can I do anything similar to this, which unfortunately does not seem to work? if (! empty ($course->pivot->participant_role == 'instructor') ) { // do something... } The shorter the answer, the better :-). Thanks a lot!

  Read the article

• Python class structure ... prep() method?

  - by Adam Nelson

  We have a metaclass, a class, and a child class for an alert system: class AlertMeta(type): """ Metaclass for all alerts Reads attrs and organizes AlertMessageType data """ def __new__(cls, base, name, attrs): new_class = super(AlertMeta, cls).__new__(cls, base, name, attrs) # do stuff to new_class return new_class class BaseAlert(object): """ BaseAlert objects should be instantiated in order to create new AlertItems. Alert objects have classmethods for dequeue (to batch AlertItems) and register (for associated a user to an AlertType and AlertMessageType) If the __init__ function recieves 'dequeue=True' as a kwarg, then all other arguments will be ignored and the Alert will check for messages to send """ __metaclass__ = AlertMeta def __init__(self, **kwargs): dequeue = kwargs.pop('dequeue',None) if kwargs: raise ValueError('Unexpected keyword arguments: %s' % kwargs) if dequeue: self.dequeue() else: # Do Normal init stuff def dequeue(self): """ Pop batched AlertItems """ # Dequeue from a custom queue class CustomAlert(BaseAlert): def __init__(self,**kwargs): # prepare custom init data super(BaseAlert, self).__init__(**kwargs) We would like to be able to make child classes of BaseAlert (CustomAlert) that allow us to run dequeue and to be able to run their own __init__ code. We think there are three ways to do this: Add a prep() method that returns True in the BaseAlert and is called by __init__. Child classes could define their own prep() methods. Make dequeue() a class method - however, alot of what dequeue() does requires non-class methods - so we'd have to make those class methods as well. Create a new class for dealing with the queue. Would this class extend BaseAlert? Is there a standard way of handling this type of situation?

  Read the article

• Sending a password securely using gwt and app engine?

  - by user246114

  Hi, I set up session handling on a google app project. This is supposed to allow my users to login and maintain state across pages. I just dumped it into the default greeting service to try it out: public class GreetingServiceImpl extends RemoteServiceServlet implements GreetingService { public void sessionTest(String username) { HttpSession session = getThreadLocalRequest().getSession(false); session.setAttribute("username", username); } } then attempting to pull it out in my landing project.jsp page: <% String username = null; HttpSession mysession = request.getSession(false); if (mysession.getAttribute("username") != null) { username = (String)mysession.getAttribute("username"); } else { username = "(not logged in yet)"; } <p>You are: <%= username %> </p> %> It works, but I don't know how to send the data in sessionTest() securely. If I were sending the user's password in there too, it would be in the clear. This would be ok (I think) if I was using https, but google app engine does not allow you to use https under custom domains (like www.mysite.com), they have to be under the (mysite.appspot.com) domain. I'm kind of stuck here - how do we send passwords securely? If I was using php, I think I could use digest authentication (I'm not too experienced here) - can we do something like that with gwt + gae? Thanks

  Read the article

• Externally disabling signals for a Linux program.

  - by Harry

  Hello, On Linux, is it possible to somehow disable signaling for programs externally... that is, without modifying their source code? Context: I'm calling a C (and also a Java) program from within a bash script on Linux. I don't want any interruptions for my bash script, and for the other programs that the script launches (as foreground processes). While I can use a... trap '' INT ... in my bash script to disable the Ctrl C signal, this works only when the program control happens to be in the bash code. That is, if I press Ctrl C while the C program is running, the C program gets interrupted and it exits! This C program is doing some critical operation because of which I don't want it be interrupted. I don't have access to the source code of this C program, so signal handling inside the C program is out of question. #!/bin/bash trap 'echo You pressed Ctrl C' INT # A C program to emulate a real-world, long-running program, # which I don't want to be interrupted, and for which I # don't have the source code! # # File: y.c # To build: gcc -o y y.c # # #include <stdio.h> # int main(int argc, char *argv[]) { # printf("Performing a critical operation...\n"); # for(;;); // Do nothing forever. # printf("Performing a critical operation... done.\n"); # } ./y Regards, /HS

  Read the article

• Jquery / PhP / Joomla Select one of two comboboxes does not get updated

  - by bluesbrother

  I am making a Joomla component wich has 3 comboboxes/selects on the page. One with languages and 2 with subjects. If you change the language the other two get filled with the same data (the subjects in the selected language) the name of the selectbox are different but otherwise the same. I get an error for one of the subject boxes (hence the url gets red), but there is no logic in wich one will give an error. In Firebug i get the HTML back for the one without the other and this one gets updated but the other one gives nothing back. If i right click in firebug on the one that gave the error, and do "send again" it will load fine. Is their a timing problem? The change event of the language selectbox: jQuery('#cmbldcoi_ldlink_language').bind('change', function() { var cmbLangID = jQuery('#cmbldcoi_ldlink_language').val(); if (cmbLangID !=0) { getSubjectCmb_lang(cmbLangID, 'cmbldcoi_ldlink_subjects', '#ldlinksubjects'); } }); Function that requests the php file to create the html for the select: function getSubjectCmb_lang(langID, cmbName, DivWhereIn) { var xdate = new Date().getTime(); var url = 'index.php?option=com_ldadmin&view=ldadmin&format=raw&task=getcmbsubj_lang&langid=' + langID + '&cmbname=' + cmbName + '&'+ xdate; jQuery(DivWhereIn).load(url, function(){ }); } And in the php file there is a connection made to the database to ge the information to build the selectbox. I use a function for this that is okay because it makes al my selectboxes. The only place where there are problems with select boxes is on the pages that has 2 selects that need to change when a third one changed. My guess it is somewhere in the Jquery where this goes wrong. And i think it has to do with timing. But i am open for all sugestions. Thanx. UPDATE: No the ID and Name fields are different. They are named : cmbldcoi_child cmbldcoi_parent Here is my code: The change event for the first combobox which makes the other two change: jQuery('#cmbldcoi_language_chain_subj').bind('change', function(){ var langID = jQuery('#cmbldcoi_language_chain_subj').val(); if (langID != 0){ getSubjectCmb_lang(langID, 'cmbldcoi_child', '#div_cmbldcoi_child'); getSubjectCmb_lang(langID, 'cmbldcoi_parent', '#div_cmbldcoi_parent'); } }); } The function wicht calls the php file to get the info from the database: function getSubjectCmb_lang(langID, cmbName, DivWhereIn){ var xdate = new Date().getTime(); var url = 'index.php?option=com_ldadmin&view=ldadmin&format=raw&task=getcmbsubj_lang&langid=' + langID + '&cmbname=' + cmbName + '&'+ xdate; jQuery(DivWhereIn).load(url, function(){ }); } The PHP code function getcmbsubj_lang(){ $langid = JRequest::getVar('langid'); if ($langid > 0 ){ $langid = JRequest::getVar('langid'); }else{ $langid = 1; } $cmbName = JRequest::getVar('cmbname'); //$lang_sufx = self::get_#__sufx($langid); print ld_html::ld_create_cmb_html($cmbName, '#__ldcoi_subjects','id', 'subject_name', " WHERE id_language={$langid} ORDER BY subject_name" ); } There is a class wich is called ld_html wich has an funnction in it that creates a combobox. ld_html::ld_create_cmb_html() It gets an table name, id field, namefield and optional an where clause. It all works fine if there is just one combobox thats needs updating. It give a problem when there are two. Thanks for the help !

  Read the article

• Why is Apache + Rails is spitting out two status headers for code 500?

  - by Daniel Beardsley

  I have a rails app that is working fine except for one thing. When I request something that doesn't exist (i.e. /not_a_controller_or_file.txt) and rails throws a "No Route matches..." exception, the response is this (blank line intentional): HTTP/1.1 200 OK Date: Thu, 02 Oct 2008 10:28:02 GMT Content-Type: text/html Content-Length: 122 Vary: Accept-Encoding Keep-Alive: timeout=15, max=100 Connection: Keep-Alive Status: 500 Internal Server Error Content-Type: text/html <html><body><h1>500 Internal Server Error</h1></body></html> I have the ExceptionLogger plugin in /vendor, though that doesn't seem to be the problem. I haven't added any error handling beyond the custom 500.html in public (though the response doesn't contain that HTML) and I have no idea where this bit of html is coming from. So Something, somewhere is adding that HTTP/1.1 200 status code too early, or the Status: 500 too late. I suspect it's Apache because I get the appropriate HTTP/1.1 500 header (at the top) when I use Webrick. My production stack is as follows: Apache 2 Mongrel (5 instances) RubyOnRails 2.1.1 (happens in both 1.2 and 2.1.1) I forgot to mention, the error is caused by a "no route matches..." exception

  Read the article

• MVC JsonResult with the [Authorize] attribute going to Logon but not displaying the view

  - by likestoski

  I am seeing odd behavior with MVC 3 methods that return a JsonResult when used with the Authorize attribute. What looks like happens is the Authorize is correctly evaluated when I am not logged in but instead of redirecting to the logon form the Json response is the logon form. Is there an addition attribute that directs the response to not return a value but instead redirect the user to the logon form, preferebly with the correct returnUrl value? What I did as a demo was to setup a new MVC3 site and added AspNetMembership to my DB using the aspnet_regsql.exe command. All that is setup and logging me in correctly. The behavior of the JsonResult doesn't seem right and I'm hoping I have just missed an attribute to make it work properly. Any help is greatly appreciated, thanks in advance. Here is the Account Controller (leaving out the Post action which is not part of this question). public class AccountController : Controller { public ActionResult LogOn() { return View(); } [Authorize] public JsonResult AuthorizedAction() { return Json("Only returns if I am authorized"); } } Here is the Html markup: <script src="@Url.Content("~/Scripts/jquery-ui-1.8.11.min.js")" type="text/javascript"></script> <script type="text/javascript"> $(document).ready(function () { $("#btnTest").click(function () { $.ajax({ type: "POST", url: "Account/AuthorizedAction", data: {}, success: function (result) { $("#testMe").html(result); }, error: function (result) { $("#testMe").html('Something broke in the ajax request'); } }); }); }); </script> <input type="button" id="btnTest" value="Test me" /> <div id="testMe">I have initial text</div> The Result: 1) When logged in I get 'Only returns if I am authorized' in my test div 2) When not logged and I have a break point in my Logon() method I see this value Request["returnUrl"] "/Account/AuthorizedAction" The test div I have displays the logon form :) this seems like I'm just not handling this properly.

  Read the article

• Is it not possible to make a C++ application "Crash Proof"?

  - by Enno Shioji

  Let's say we have an SDK in C++ that accepts some binary data (like a picture) and does something. Is it not possible to make this SDK "crash-proof"? By crash I primarily mean forceful termination by the OS upon memory access violation, due to invalid input passed by the user (like an abnormally short junk data). I have no experience with C++, but when I googled, I found several means that sounded like a solution (use a vector instead of an array, configure the compiler so that automatic bounds check is performed, etc.). When I presented this to the developer, he said it is still not possible.. Not that I don't believe him, but if so, how is language like Java handling this? I thought the JVM performs everytime a bounds check. If so, why can't one do the same thing in C++ manually? UPDATE By "Crash proof" I don't mean that the application does not terminate. I mean it should not abruptly terminate without information of what happened (I mean it will dump core etc., but is it not possible to display a message like "Argument x was not valid" etc.?)

  Read the article

• Java redirected system output to jtext area, doesnt update until calculation is finished

  - by user1806716

  I have code that redirects system output to a jtext area, but that jtextarea doesnt update until the code is finished running. How do I modify the code to make the jtextarea update in real time during runtime? private void updateTextArea(final String text) { SwingUtilities.invokeLater(new Runnable() { public void run() { consoleTextAreaInner.append(text); } }); } private void redirectSystemStreams() { OutputStream out = new OutputStream() { @Override public void write(int b) throws IOException { updateTextArea(String.valueOf((char) b)); } @Override public void write(byte[] b, int off, int len) throws IOException { updateTextArea(new String(b, off, len)); } @Override public void write(byte[] b) throws IOException { write(b, 0, b.length); } }; System.setOut(new PrintStream(out, true)); System.setErr(new PrintStream(out, true)); } The rest of the code is mainly just an actionlistener for a button: private void updateButtonActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: String shopRoot = this.shopRootDirTxtField.getText(); String updZipPath = this.updateZipTextField.getText(); this.mainUpdater = new ShopUpdater(new File(shopRoot), updZipPath); this.mainUpdater.update(); } That update() method begins the process of copying+pasting files on the file system and during that process uses system.out.println to provide an up-to-date status on where the program is currently at in reference to how many more files it has to copy.

  Read the article

• What database options do I have for the Blackberry?

  - by peeping-jane

  I notice most of the discussions about Blackberry database options are old, and generally not too informative. As of today, March 31st, 2010, what is the best, most universally supported, free database option available for Blackberry developers? I heard SQLite is available for JDE v5, but last I checked, that was still in beta, and I didn't want to commit to developing on a system that is not supported by most of the phones in service. Thing is, I don't see any dates on these claims. For all I know, the announcements I am reading are from 2008. So, I am still on v 4.7. I need to use a relational DB for the app I am developing, but there aren't many resources for DB handling available - or at least resources that are useful to me. I find a lot of "tutorials" that assume you know everything there is to know about Blackberry development, or Java. But no complete classes or anything. Many of these examples don't even work. Eclipse gives warnings and errors from code copied and pasted from other people's examples. I can answer any questions that may assist in this case. Hopefully, this thread will help many BB developers in the future.

  Read the article

• Simulating a 2-level If-Else using RewriteCond

  - by hlissner

  Hi! I'm trying to get my head around RewriteCond, and want to rewrite any requests either to a static html page (if it exists), or to a specific index.php (so long as the requested file doesn't exist). To illustrate the logic: if HTTP_HOST is '(www\.)?mydomain.com' if file exists: "/default/static/{REQUEST_URI}.html", then rewrite .* to /default/static/{REQUEST_URI}.html else if file exists: {REQUEST_FILENAME}, then do not rewrite else rewrite .* to /default/index.php I don't seem to have much trouble doing it when I don't need to test for the HTTP_HOST. Ultimately, this one .htaccess file will be handling requests for several domains. I know I could get around this with vhosts, but I'd like to figure out how to do it this way. Here's where I am at now: RewriteCond %{HTTP_HOST} ^(www\.)?mydomain\.com$ [NC] RewriteCond /default/static/%{REQUEST_URI}.html -f RewriteRule . /default/static/%{REQUEST_URI}.html [L,NC] RewriteCond %{REQUEST_FILENAME} !-f RewriteRule . /default/index.php [L,QSA] I'm not too familiar with some of the other flags, will any of them be of use here (like chain|C, next|N or skip|S)? Thanks in advance! UPDATE: I've managed to do it, but would appreciate alternatives: RewriteEngine On RewriteRule ^(.+)/$ /$1 [L] RewriteCond %{HTTP_HOST} ^(domainA|domainB)\.com [NC] RewriteCond %{DOCUMENT_ROOT}/%1/static/%{REQUEST_URI}.html -f RewriteRule (.*)? /%1/static/$1.html [NC,L] RewriteCond %{HTTP_HOST} ^(domainA|domainB)\.com [NC] RewriteCond %{REQUEST_FILENAME} !-f RewriteRule .* /%1/index.php [L,QSA]

  Read the article

• TCP/IP Implementation General Questions

  - by user2971023

  I've implemented the concepts shown here; http://wiki.unity3d.com/index.php/Simple_TCP/IP_Client_-_Server outside of unity and it works. (though i had to create the TCPIPServerApp from scratch as i could not find the base project anywhere). I have some general questions on how to use tcp/ip properly however. I've done some research on tcp/ip itself but I'm still a little confused. It seems like using the method above doesn't guarantee that I'll see the message (res). It just checks on every update to see if there is a different message in res. What if multiple messages are sent and the program lags or something, will i miss the earlier packet(s)? Should i instead do an array so it stores the last X messages? How do i know the data was received? Do I need to add a message id and build in my own ack into the data? Should i check to see if the port is in use before setting up a connection? Sorry for all the questions. This is all new to me but I enjoy this very much! ... Below already answered By Anton, Thanks It sounds like tcp uses its own packet numbering to ensure the packets end up in the right order on the other side. What if a packet is missed, are the subsequent packets thrown away? Or is this numbering and packet ordering, only for handling data that is broken out into multiple packets? TCP will automatically break the data into multiple packets if necessary right?

  Read the article

• NULL pointer dereference in swiotlb_unmap_sg_attrs() on disk IO

  - by Inductiveload

  I'm getting an error I really don't understand when reading or writing files using a PCIe block device driver. I seem to be hitting an issue in swiotlb_unmap_sg_attrs(), which appears to be doing a NULL dereference of the sg pointer, but I don't know where this is coming from, as the only scatterlist I use myself is allocated as part of the device info structure and persists as long as the driver does. There is a stacktrace to go with the problem. It tends to vary a bit in exact details, but it always crashes in swiotlb_unmap_sq_attrs(). I think it's likely I have a locking issue, as I am not sure how to handle the locks around the IO functions. The lock is already held when the request function is called, I release it before the IO functions themselves are called, as they need an (MSI) IRQ to complete. The IRQ handler updates a "status" value, which the IO function is waiting for. When the IO function returns, I then take the lock back up and return to request queue handling. The crash happens in blk_fetch_request() during the following: if (!__blk_end_request(req, res, bytes)){ printk(KERN_ERR "%s next request\n", DRIVER_NAME); req = blk_fetch_request(q); } else { printk(KERN_ERR "%s same request\n", DRIVER_NAME); } where bytes is updated by the request handler to be the total length of IO (summed length of each scatter-gather segment).

  Read the article

• C#: Determine Type for (De-)Serialization

  - by dbemerlin

  Hi, i have a little problem implementing some serialization/deserialization logic. I have several classes that each take a different type of Request object, all implementing a common interface and inheriting from a default implementation: This is how i think it should be: Requests interface IRequest { public String Action {get;set;} } class DefaultRequest : IRequest { public String Action {get;set;} } class LoginRequest : DefaultRequest { public String User {get;set;} public String Pass {get;set;} } Handlers interface IHandler<T> { public Type GetRequestType(); public IResponse HandleRequest(IModel model, T request); } class DefaultHandler<T> : IHandler<T> // Used as fallback if the handler cannot be determined { public Type GetRequestType() { return /* ....... how to get the Type of T? ((new T()).GetType()) ? .......... */ } public IResponse HandleRequest(IModel model, T request) { /* ... */ } } class LoginHandler : DefaultHandler<LoginRequest> { public IResponse HandleRequest(IModel mode, LoginRequest request) { } } Calling class Controller { public ProcessRequest(String action, String serializedRequest) { IHandler handler = GetHandlerForAction(action); IRequest request = serializer.Deserialize<handler.GetRequestType()>(serializedRequest); handler(this.Model, request); } } Is what i think of even possible? My current Solution is that each handler gets the serialized String and is itself responsible for deserialization. This is not a good solution as it contains duplicate code, the beginning of each HandleRequest method looks the same (FooRequest request = Deserialize(serializedRequest); + try/catch and other Error Handling on failed deserialization). Embedding type information into the serialized Data is not possible and not intended. Thanks for any Hints.

  Read the article

• Python - Access a class from a list using a key

  - by Fake Name

  Is there any way to make a list of classes behave like a set in python? Basically, I'm working on a piece of software that does some involved string comparison, and I have a custom class for handling the strings. Therefore, there is an instance of the class for each string. As a result, I have a large list containing all these classes. I would like to be able to access them like list[key], where in this case, the key is a string the class is based off of. It seems to me that I sould be able to do this somewhat easily, by adding something like __cmp__ to the class, but either I'm being obtuse (likely), or Im missing someting in the docs. Basically, I want to be able to do something like this (Python prompt example): >>class a: ... def __init__(self, x): ... self.var = x ... >>> from test import a >>> cl = set([a("Hello"), a("World"), a("Pie")]) >>> print cl set([<test.a instance at 0x00C866C0>, <test.a instance at 0x00C866E8>, <test.a instance at 0x00C86710>]) >>> cl["World"] <test.a instance at 0x00C866E8> Thanks!

  Read the article

• Design pattern for loading multiple message types

  - by lukem00

  As I was looking through SO I came across a question about handling multiple message types. My concern is - how do I load such a message in a neat way? I decided to have a separate class with a method which loads one message each time it's invoked. This method should create a new instance of a concrete message type (say AlphaMessage, BetaMessage, GammaMessage, etc.) and return it as a Message. class MessageLoader { public Message Load() { // ... } } The code inside the method is something which looks really awful to me and I would very much like to refactor it/get rid of it: Message msg = Message.Load(...); // load yourself from whatever source if (msg.Type == MessageType.Alpha) return new AlphaMessage(msg); if (msg.Type == MessageType.Beta) return new BetaMessage(msg); // ... In fact, if the whole design looks just too messy and you guys have a better solution, I'm ready to restructure the whole thing. If my description is too chaotic, please let me know what it's missing and I shall edit the question. Thank you all.

  Read the article

• Dimensions of a collection, and how to traverse it in an efficient, elegant manner

  - by Bruce Ferguson

  I'm trying to find an elegant way to deal with multi-dimensional collections in Scala. My understanding is that I can have up to a 5 dimensional collection using tabulate, such as in the case of the following 2-Dimensional array: val test = Array.tabulate[Double](row,col)(_+_) and that I can access the elements of the array using for(i<-0 until row) { for(j<-0 until col) { test(i)(j) = 0.0 } } If I don't know a priori what I'm going to be handling, what might be a succinct way of determining the structure of the collection, and spanning it, without doing something like: case(Array(x)) => for(i<-1 until dim1) { test(i) = 0.0 } case(Array(x,y)) => for(i<-1 until dim1) { for(j<-1 until dim2) { test(i)(j) = 0.0 } } case(Array(x,y,z)) => ... The dimensional values n1, n2, n3, etc... are private, right? Also, would one use the same trick of unwrapping a 2-D array into a 1-D vector when dealing with n-Dimensional objects if I want a single case to handle the traversal? Thanks in advance Bruce

  Read the article

• Automating Excel through the PIA makes VBA go squiffy.

  - by Jon Artus

  I have absolutely no idea how to start diagnosing this, and just wondered if anyone had any suggestions. I'm generating an Excel spreadsheet by calling some Macros from a C# application, and during the generation process it somehow breaks. I've got a VBA class containing all of my logging/error-handling logic, which I instantiate using a singleton-esque accessor, shown here: Private mcAppFramework As csys_ApplicationFramework Public Function AppFramework() As csys_ApplicationFramework If mcAppFramework Is Nothing Then Set mcAppFramework = New csys_ApplicationFramework Call mcAppFramework.bInitialise End If Set AppFramework = mcAppFramework End Function The above code works fine before I've generated the spreadsheet, but afterwards fails. The problem seems to be the following line; Set mcAppFramework = New csys_ApplicationFramework which I've never seen fail before. If I add a watch to the variable being assigned here, the type shows as csys_ApplicationFramework/wksFoo, where wksFoo is a random worksheet in the same workbook. What seems to be happening is that while the variable is of the right type, rather than filling that slot with a new instance of my framework class, it's making it point to an existing worksheet instead, the equivalent of Set mcAppFramework = wksFoo which is a compiler error, as one might expect. Even more bizarrely, if I put a breakpoint on the offending line, edit the line, and then resume execution, it works. For example, I delete the word 'New' move off the line, move back, re-type 'New' and resume execution. This somehow 'fixes' the workbook and it works happily ever after, with the type of the variable in my watch window showing as csys_ApplicationFramework/csys_ApplicationFramework as I'd expect. This implies that manipulating the workbook through the PIA is somehow breaking it temporarily. All I'm doing in the PIA is opening the workbook, calling several macros using Excel.Application.Run(), and saving it again. I can post a few more details if anyone thinks that it's relevant. I don't know how VBA creates objects behind the scenes or how to debug this. I also don't know how the way the code executes can change without the code itself changing. As previously mentioned, VBA has frankly gone a bit squiffy on me... Any thoughts?

  Read the article

• Does Spring MVC form submit data bind children objects automagically?

  - by predhme

  I have a data model that is something like this: public class Report { // report owner private User user; ... typical getter setter ... } public class User { ... omitted for clarity } What happens is when a report is created, the current user is set to the report user object. When the report is edited, the spring controller handling the POST request is receiving a report where the user object is null. Here is what my controller looks like: @Controller @RequestMapping("/report") public class ReportController { @RequestMapping(value = "/edit/{id}", method = RequestMethod.GET) public String editReport(@PathVariable Long id, Model model) { Report r = backend.getReport(id); // fully loads object model.addAttribute("report", report); return "report/edit"; } @RequestMapping(value = "/edit/{id}", method = RequestMethod.POST) public String process(@ModelAttribute("report") Report r) { backend.save(r); return "redirect:/report/show" + r.getId(); } } I ran things throw the debugger and it looks like in the editReport method the model object is storing the fully loaded report object (I can see the user inside the report). On the form jsp I can do the following: ${report.user.username} and the correct result is rendered. However, when I look at the debugger in the process method, the passed in Report r has a null user. I don't need to do any special data binding to ensure that information is retained do I?

  Read the article

• How can I hide this overlay element intelligently?

  - by inkedmn

  The site I'm working on has a collection of navigation elements across the top ("Products", "Company", etc.). When you mouse over the Products link, an overlay appears that shows a list of products with links to each. There's a small link at the top of the container that, when clicked, closes the container. All of this works as advertised. The client has asked that, once a user's mouse pointer is a sufficient distance from the overlay element, the overlay element would close (without them having to click the 'close' link). This element appears on multiple pages that have disparate content, so I'm afraid it won't be as simple as adding a mouseover listener to another single element within the page and have it work everywhere. My question, I suppose, is this: is there a relatively easy way to know when the mouse cursor is x pixels away from this container and trigger an event when this occurs? My other thought is that I could just find several elements on the page that fit this criteria and add mouseover listeners to each, but I'm assuming there's a more elegant way of handling this. Thanks in advance - and please let me know if more detail is needed.

  Read the article

• Database solution for 200million writes/day, monthly summarization queries

  - by sb

  Hello. I'm looking for help deciding on which database system to use. (I've been googling and reading for the past few hours; it now seems worthwhile to ask for help from someone with firsthand knowledge.) I need to log around 200 million rows (or more) per 8 hour workday to a database, then perform weekly/monthly/yearly summary queries on that data. The summary queries would be for collecting data for things like billing statements, eg. "How many transactions of type A did each user run this month?" (could be more complex, but that's the general idea). I can spread the database amongst several machines, as necessary, but I don't think I can take old data offline. I'll definitely need to be able to query a month's worth of data, maybe a year. These queries would be for my own use, and wouldn't need to be generated in real-time for an end-user (they could run overnight, if needed). Does anyone have any suggestions as to which databases would be a good fit? P.S. Cassandra looks like it would have no problem handling the writes, but what about the huge monthly table scans? Is anyone familiar with Cassandra/Hadoop MapReduce performance?

  Read the article

• How to set up site specific configuration vs application configuration in Zend Framework?

  - by rbruhn

  Being fairly new to Zend Framework, I've been reading and trying out various tutorials on the web and books I've purchased. One thing all the tutorials do is hard code certain values into into the bootstrap or other code. For example, setting the title: $this-_view-headTitle('MySite'); I realize this can be set in the application.ini file, but I don't think that is appropriate either if you are distributing the application to other sites. I would be interested in hearing ideas where application specific settings are set in the application.ini file and loaded: $application = new Zend_Application( APPLICATION_ENV, APPLICATION_PATH.'/configs/application.ini' ); Then somewhere in the bootstrap, checking for a config.ini file and adding these to currently existing application config array, and if config.ini does not exist, retrieving such site specific configs from a database and writing the config.ini file (Obviously the file deleted and rewritten if a value is changed in the database). I don't need to see how the file is written or what not... just a general idea of how others are handling such things. Or provide different ideas of doing this? I would rather end up using something like this when setting various site specific configurations: $this->_view->headTitle($config->site->title); Hope this makes sense :-)

  Read the article

< Previous Page | 554 555 556 557 558 559 560 561 562 563 564 565  | Next Page >