Search Results

Search found 22384 results on 896 pages for 'customer support'.

Page 804/896 | < Previous Page | 800 801 802 803 804 805 806 807 808 809 810 811  | Next Page >

• Manage multiple UDP calls

  - by rayman

  Hi all, I would like to have an advice for this issue: I am using Jbos 5.1.0, EJB3.0 I have system, which sending requests via UDP'S to remote modems, and suppose to wait for an answer from the target modem. the remote modems support only UDP calls, therefor I o design asynchronous mechanism. (also coz I want to request X modems parallel) this is what I try to do: all calls are retrieved from Data Base, then each call will be added as a message to JMS QUE. let's say i will set X MDB'S on that que, so I can work asynchronous. now each MDB will send UDP request to the IP-address(remote modem) which will be parsed from the que message. so basicly each MDB, which takes a message is sending a udp request to the remote modem and [b]waiting [/b]for an answer from that modem. [u]now here is the BUG:[/u] could happen a scenario where MDB will get an answer, but not from the right modem( which it requested in first place). that bad scenario cause two wrong things: a. the sender which sent the message will wait forever since the message never returned to him(it got accepted by another MDB). b. the MDB which received the message is not the right one, and probablly if it was on a "listener" mode, then it supposed to wait for an answer from diffrent sender.(else it wouldnt get any messages) so ofcourse I can handle everything with a RETRY mechanisem. so both mdb's(the one who got message from the wrong sender, and the one who never got the answer) will try again, to do thire operation with a hope that next time it will success. This is the mechanism, mybe you could tell me if there is any design pattren, or any other effective solution for this problem? Thanks, ray.

  Read the article

• I need a fast runtime expression parser

  - by Chris Lively

  I need to locate a fast, lightweight expression parser. Ideally I want to pass it a list of name/value pairs (e.g. variables) and a string containing the expression to evaluate. All I need back from it is a true/false value. The types of expressions should be along the lines of: varA == "xyz" and varB==123 Basically, just a simple logic engine whose expression is provided at runtime. UPDATE At minimum it needs to support ==, !=, , =, <, <= Regarding speed, I expect roughly 5 expressions to be executed per request. We'll see somewhere in the vicinity of 100/requests a second. Our current pages tend to execute in under 50ms. Usually there will only be 2 or 3 variables involved in any expression. However, I'll need to load approximately 30 into the parser prior to execution. UPDATE 2012/11/5 Update about performance. We implemented nCalc nearly 2 years ago. Since then we've expanded it's use such that we average 40+ expressions covering 300+ variables on post backs. There are now thousands of post backs occurring per second with absolutely zero performance degradation. We've also extended it to include a handful of additional functions, again with no performance loss. In short, nCalc met all of our needs and exceeded our expectations.

  Read the article

• Database and logic layer for ASP.NET MVC application

  - by Ismail

  I'm going to start a new project which is going to be small initially but may grow to big over the years. I'm strongly convinced that I'm going to use ASP.NET MVC with jQuery for UI. I want to go for MySQL as database for some reasons but worried on few things. I've a good years of experience working on SQL Server databases and on one project I've had a bad experience creating and managing stored procedures on MySQL database. I'm totally new to Linq but I see that it is easier to use once you are familiar with it. First thing is that accessing data should be easy. So I thought I should use MySQL to Linq but somewhere I read that it is not directly supported but MySQL .NET connector adds support for EntityFramework. I don't know what are the pros and cons of it. I would love if I can implement repository pattern as it allows to apply filter in logic layer rather than in data access layer. Will it be possible if I use Entity Framework? I'm not clear on how I should go about all this or I should just forget every thing and directly use SQL to Linq on SQL Server. I'm also concerned about the performance. Someone told me that if we use Entity framework it fetches lot of data and then filter it. Is that right? So questions basically are - Is MySQL to Linq possible? If yes where can I get more details on it? Pros and cons of using EntityFramework with MySQL? Will it be easy to access data using EntityFramework with MySQL? Will I be able to implement repository patter which allows applying filter in logic layer rather than data access layer (when I use EntityFramework with MySQL) Does it fetches hell lot of data from database and then apply filter on it? If it sounds too many questions from my side in that case, if you can just let me know what you will do (with a considerable reason) in this situation as an experienced person in this area, that should answer my question.

  Read the article

• Using ControllerClassNameHandlerMapping with @Controller and extending AbstractController

  - by whiskerz

  Hey there, actually I thought I was trying something really simple. ControllerClassNameHandlerMapping sounded great to produce a small spring webapp using a very lean configuration. Just annotate the Controller with @Controller, have it extend AbstractController and the configuration shouldn't need more than this <context:component-scan base-package="test.mypackage.controller" /> <bean id="urlMapping" class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping" /> to resolve my requests and map them to my controllers. I've mapped the servlet to "*.spring", and calling <approot>/hello.spring All I ever get is an error stating that no mapping was found. If however I extend the MultiActionController, and do something like <approot>/hello/hello.spring it works. Which somehow irritates me, as I would have thought that if that is working, why didn't my first try? Does anyone have any idea? The two controllers I used looked like this @Controller public class HelloController extends AbstractController { @Override protected ModelAndView handleRequestInternal(HttpServletRequest request, HttpServletResponse response) throws Exception { ModelAndView modelAndView = new ModelAndView("hello"); modelAndView.addObject("message", "Hello World!"); return modelAndView; } } and @Controller public class HelloController extends MultiActionController { public ModelAndView hello(HttpServletRequest request, HttpServletResponse response) throws Exception { ModelAndView modelAndView = new ModelAndView("hello"); modelAndView.addObject("message", "Hello World!"); return modelAndView; } }

  Read the article

• pthread condition variables on Linux, odd behaviour.

  - by janesconference

  Hi. I'm synchronizing reader and writer processes on Linux. I have 0 or more process (the readers) that need to sleep until they are woken up, read a resource, go back to sleep and so on. Please note I don't know how many reader processes are up at any moment. I have one process (the writer) that writes on a resource, wakes up the readers and does its business until another resource is ready (in detail, I developed a no starve reader-writers solution, but that's not important). To implement the sleep / wake up mechanism I use a Posix condition value, pthread_cond_t. The clients call a pthread_cond_wait() on the variable to sleep, while the server does a pthread_cond_broadcast() to wake them all up. As the manual says, I surround these two calls with a lock/unlock of the associated pthread mutex. The condition variable and the mutex are initialized in the server and shared between processes through a shared memory area (because I'm not working with threads, but with separate processes) an I'm sure my kernel / syscall support it (because I checked _POSIX_THREAD_PROCESS_SHARED). What happens is that the first client process sleeps and wakes up perfectly. When I start the second process, it blocks on its pthread_cond_wait() and never wakes up, even if I'm sure (by the logs) that pthread_cond_broadcast() is called. If I kill the first process, and launch another one, it works perfectly. In other words, the condition variable pthread_cond_broadcast() seems to wake up only one process a time. If more than one process wait on the very same shared condition variable, only the first one manages to wake up correctly, while the others just seem to ignore the broadcast. Why this behaviour? If I send a pthread_cond_broadcast(), every waiting process should wake up, not just one (and, however, not always the same one).

  Read the article

• Duplicating custom nodes in JavaFX

  - by Elazar Leibovich

  As far as I understand, duplicating nodes in JavaFX should be done with the Duplicator.duplicate function. It works fine when duplicating nodes whose types are included in JavaFX library, for example def dup = Duplicator.duplicate(Rectangle{x:30 y:30 width:100 height:100}); dup.translateX = 10; insert dup into content; would insert a black rectangle to the scene. However if I define a new class in the following way: class MyRect extends Rectangle {} Or class MyRect extends CustomNode { override function create() {Rectangle{x:30 y:30 width:10 height:10}} } It gives me the following runtime error Type 'javafxapplication1.NumberGrid$MyRect' not found. Where of course javafxapplication1.NumberGrid are the package and file the MyRect class is in. This guy at Sun's forums had the same problem, but I don't see any answer in there. Or maybe I'm doing that the wrong way, and there's a better approach for duplicating custom nodes? update: Trying to duplicate Group worked, but trying to duplicate Stack yields the same error. According to the documentation, it's supposed to support all types supported in FXD including Node, but maybe it supports only some of Node's descendants?

  Read the article

• "Could not establish secure channel for SSL/TLS" in .NET CF application on smart phone

  - by Stefan Mohr

  I have a stubborn communications issue with an application running on the .NET Compact Framework 3.5 on Windows Mobile smartphones. I am constructing a web request using this code: UTF8Encoding encoding = new System.Text.UTF8Encoding(); byte[] Data = encoding.GetBytes(HttpUtility.ConstructQueryString(parameters)); httpRequest = WebRequest.Create((domain)) as HttpWebRequest; httpRequest.Timeout = 10000000; httpRequest.ReadWriteTimeout = 10000000; httpRequest.Credentials = CredentialCache.DefaultCredentials; httpRequest.Method = "POST"; httpRequest.ContentType = "application/x-www-form-urlencoded"; httpRequest.ContentLength = Data.Length; Stream SendReq = httpRequest.GetRequestStream(); SendReq.Write(Data, 0, Data.Length); SendReq.Close(); HttpWebResponse httpResponse = (HttpWebResponse)httpRequest.GetResponse(); return httpResponse.GetResponseStream(); The web service functions by receiving a JSON-encoded document as part of the URL (eg. https://site.com/ws/sync??document={"version":"1.0.0","items":[{"item_1":"item1"}]}&user=usr&password=pw), and as a response receives another JSON document as response data. This code runs fine on all emulators and PDAs running WM 5 and 6. We have seen an issue with a couple of customers running Treo smartphones (and only on the Sprint network). We have tested the code on an identical device on the AT&T network (via DeviceAnywhere) and once again the code worked as we expected. This has to be some sort of security policy on the phone, but we've been unable to determine a workaround or diagnose it thoroughly as we cannot reproduce it in house and have had to resort to getting users to assist with running test drivers for us. When this code executes, the user's device throws the following exception: System.Net.WebException Could not establish secure channel for SSL/TLS Stack trace: at System.Net.HttpWebRequest.finishGetRequestStream() at System.Net.HttpWebRequest.GetRequestStream() at OurApp.GetResponseStream(String domain, Hashtable parameters) inner exception: System.IO.IOException Authentication failed because the remote party has closed the transport stream. Stack trace: at System.Net.SslConnectionState.ClientSideHandshake() at System.Net.SslConnectionState.PerformClientHandShake() at System.Net.Connection.connect(Object ignored) at System.Threading.ThreadPool.WorkItem.doWork(Object o) at System.Threading.Timer.ring() Examining the server Apache logs shows no hits from the user's IP - I don't think the device is even attempting to send a packet before failing. If relevant, the server is running Apache on Linux and is written using the TurboGears Python framework. The server certificate is issued by a CA and is still valid. The test driver where this error was copied from was not code signed, however the same error (without the error messages) is signed with a GeoTrust certificate so we don't believe this is a code signing issue. The application installs and launches without issue on all phones - it's just establishing this SSL connection that is breaking for these users. One significant issue in troubleshooting is that there is a substantial inconvenience each time we try out a solution (need to find a "volunteer" customer), so we're really looking for a silver bullet or a better understanding of the handshaking process so we can be reasonably confident we only need to ask the user to test it one or two more times. One final mention: we have tried the sync both over ActiveSync and also over GPRS with identical results. Any thoughts would be greatly appreciated!

  Read the article

• Save PyML.classifiers.multi.OneAgainstRest(SVM()) object?

  - by Michael Aaron Safyan

  I'm using PYML to construct a multiclass linear support vector machine (SVM). After training the SVM, I would like to be able to save the classifier, so that on subsequent runs I can use the classifier right away without retraining. Unfortunately, the .save() function is not implemented for that classifier, and attempting to pickle it (both with standard pickle and cPickle) yield the following error message: pickle.PicklingError: Can't pickle : it's not found as __builtin__.PySwigObject Does anyone know of a way around this or of an alternative library without this problem? Thanks. Edit/Update I am now training and attempting to save the classifier with the following code: mc = multi.OneAgainstRest(SVM()); mc.train(dataset_pyml,saveSpace=False); for i, classifier in enumerate(mc.classifiers): filename=os.path.join(prefix,labels[i]+".svm"); classifier.save(filename); Notice that I am now saving with the PyML save mechanism rather than with pickling, and that I have passed "saveSpace=False" to the training function. However, I am still gettting an error: ValueError: in order to save a dataset you need to train as: s.train(data, saveSpace = False) However, I am passing saveSpace=False... so, how do I save the classifier(s)? P.S. The project I am using this in is pyimgattr, in case you would like a complete testable example... the program is run with "./pyimgattr.py train"... that will get you this error. Also, a note on version information: [michaelsafyan@codemage /Volumes/Storage/classes/cse559/pyimgattr]$ python Python 2.6.1 (r261:67515, Feb 11 2010, 00:51:29) [GCC 4.2.1 (Apple Inc. build 5646)] on darwin Type "help", "copyright", "credits" or "license" for more information. import PyML print PyML.__version__ 0.7.0

  Read the article

• Android getting XML values

  - by Nils

  Hello, I have the following XML code, which I got by a UPnP device and like to get the res value - the RTSP URL. In this case rtsp://10.42.0.103:554/live.sdp How can I do this? I heard that Android has some built-in support for reading XML. Is that true? <DIDL-Lite xmlns="urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:upnp="urn:schemas-upnp-org:metadata-1-0/upnp/"> <item id="11" parentID="1" restricted="1"> <dc:title>Network Camera Stream 1</dc:title> <upnp:class>object.item.videoItem</upnp:class> <res protocolInfo="rtsp-rtp-udp:*:video/mpeg4-generic:*" resolution="640x480">rtsp://10.42.0.103:554/live.sdp</res> </item> <item id="12" parentID="1" restricted="1"> <dc:title>Network Camera Stream 2</dc:title> <upnp:class>object.item.videoItem</upnp:class> <res protocolInfo="rtsp-rtp-udp:*:video/mpeg4-generic:*" resolution="176x144">rtsp://10.42.0.103:554/live2.sdp</res> </item> </DIDL-Lite>

  Read the article

• Is it possible to load an assembly targeting a different .NET runtime version in a new app domain?

  - by Notre

  Hello, I've an application that is based on .NET 2 runtime. I want to add a little bit of support for .NET 4 but don't want to (in the short term), convert the whole application (which is very large) to target .NET 4. I tried the 'obvious' approach of creating an application .config file, having this: <startup useLegacyV2RuntimeActivationPolicy="true"> <supportedRuntime version="v4.0" /> </startup> but I ran into some problems that I noted here. I got the idea of creating a separate app domain. To test it, I created a WinForm project targeting .NET 2. I then created a class library targeting .NET 4. In my WinForm project, I added the following code: AppDomainSetup setup = new AppDomainSetup(); setup.ApplicationBase = "path to .NET 4 assembly"; setup.ConfigurationFile = System.Environment.CurrentDirectory + "\\DotNet4AppDomain.exe.config"; // Set up the Evidence Evidence baseEvidence = AppDomain.CurrentDomain.Evidence; Evidence evidence = new Evidence(baseEvidence); // Create the AppDomain AppDomain dotNet4AppDomain = AppDomain.CreateDomain("DotNet4AppDomain", evidence, setup); try { Assembly doNet4Assembly = dotNet4AppDomain.Load( new AssemblyName("MyDotNet4Assembly, Version=1.0.0.0, Culture=neutral, PublicKeyToken=66f0dac1b575e793")); MessageBox.Show(doNet4Assembly.FullName); } finally { AppDomain.Unload(dotNet4AppDomain); } My DotNet4AppDomain.exe.config file looks like this: <startup useLegacyV2RuntimeActivationPolicy="true"> <supportedRuntime version="v4.0" /> </startup> Unfortunately, this throws the BadImageFormatException when dotNet4AppDomain.Load is executed. Am I doing something wrong in my code, or is what I'm trying to do just not going to work? Thank you!

  Read the article

• SQL Server: What locale should be used to format numeric values into SQL Server format?

  - by Ian Boyd

  It seems that SQL Server does not accept numbers formatted using any particular locale. It also doesn't support locales that have digits other than 0-9. For example, if the current locale is bengali, then the number 123456789 would come out as "?????????". And that's just the digits, nevermind what the digit grouping would be. But the same problem happens for numbers in the Invariant locale, which formats numbers as "123,456,789", which SQL Server won't accept. Is there a culture that matches what SQL Server accepts for numeric values? Or will i have to create some custom "sql server" culture, generating rules for that culture myself from lower level formatting routines? If i was in .NET (which i'm not), i could peruse the Standard Numeric Format strings. Of the format codes available in .NET: c (Currency): $123.46 d (Decimal): 1234 e (Exponentional): 1.052033E+003 f (Fixed Point): 1234.57 g (General): 123.456 n (Number): 1,234.57 p (Percent): 100.00 % r (Round Trip): 123456789.12345678 x (Hexadecimal): FF Only 6 accept all numeric types: c (Currency): $123.46 d (Decimal): 1234 e (Exponentional): 1.052033E+003 f (Fixed Point): 1234.57 g (General): 123.456 n (Number): 1,234.57 p (Percent): 100.00 % r (Round Trip): 123456789.12345678 x (Hexadecimal): FF And of those only 2 generate string representations, in the en-US locale anyway, that would be accepted by SQL Server: c (Currency): $123.46 d (Decimal): 1234 e (Exponentional): 1.052033E+003 f (Fixed Point): 1234.57 g (General): 123.456 n (Number): 1,234.57 p (Percent): 100.00 % r (Round Trip): 123456789.12345678 x (Hexadecimal): FF Of the remaining two, fixed is dependant on the locale's digits, rather than the number being used, leaving General g format: c (Currency): $123.46 d (Decimal): 1234 e (Exponentional): 1.052033E+003 f (Fixed Point): 1234.57 g (General): 123.456 n (Number): 1,234.57 p (Percent): 100.00 % r (Round Trip): 123456789.12345678 x (Hexadecimal): FF And i can't even say for certain that the g format won't add digit groupings (e.g. 1,234). Is there a locale that formats numbers in the way SQL Server expects? Is there a .NET format code? A java format code? A Delphi format code? A VB format code? A stdio format code? latin-numeral-digits

  Read the article

• Rolling back file moves, folder deletes and mysql queries

  - by Workoholic

  This has been bugging me all day and there is no end in sight. When the user of my php application adds a new update and something goes wrong, I need to be able to undo a complex batch of mixed commands. They can be mysql update and insert queries, file deletes and folder renaming and creations. I can track the status of all insert commands and undo them if an error is thrown. But how do I do this with the update statements? Is there a smart way (some design pattern?) to keep track of such changes both in the file structure and the database? My database tables are MyISAM. It would be easy to just convert everything to InnoDB, so that I can use transactions. That way I would only have to deal with the file and folder operations. Unfortunately, I cannot assume that all clients have InnoDB support. It would also require me to convert many tables in my database to InnoDB, which I am hesitant to do.

  Read the article

• Identify machines behind a router uniquely based on ipaddress

  - by Amith George

  Some background first. I have a .net client agent installed on each of the machines in the lan. They are interacting with my central server [website] also on the same lan. It is important for my website to figure out which of the machines can talk to each other. For example, machines of one subnet cannot directly talk to machines of another subnet without configuring the routers and such. But machines in the same subnet should be able to talk to each other directly. The problem I am facing is when the lan setup is like in Figure 1. Because Comp1, Comp2 and Comp3 are behind a router, they have got the ipaddress 192.168.1.2 till 192.168.1.4. My client agent on these machines report the same ipaddress back to the server. However, machines Comp4, Comp5 also have the same ipaddresses. Thus, as far as my server is concerned, there are 2 machines with the same ipaddress. Not just that, because the subnet mask is 255.255.255.0 for all machines, my server is fooled into thinking that Comp1 can directly talk to Comp5, which is not possible. So, how do I solve this? What do I need to change in my client or in my server, so that I can support this scenario. These two are the only things in my control.

  Read the article

• Why are symbols not frozen strings?

  - by Alex Chaffee

  I understand the theoretical difference between Strings and Symbols. I understand that Symbols are meant to represent a concept or a name or an identifier or a label or a key, and Strings are a bag of characters. I understand that Strings are mutable and transient, where Symbols are immutable and permanent. I even like how Symbols look different from Strings in my text editor. What bothers me is that practically speaking, Symbols are so similar to Strings that the fact that they're not implemented as Strings causes a lot of headaches. They don't even support duck-typing or implicit coercion, unlike the other famous "the same but different" couple, Float and Fixnum. The mere existence of HashWithIndifferentAccess, and its rampant use in Rails and other frameworks, demonstrates that there's a problem here, an itch that needs to be scratched. Can anyone tell me a practical reason why Symbols should not be frozen Strings? Other than "because that's how it's always been done" (historical) or "because symbols are not strings" (begging the question). Consider the following astonishing behavior: :apple == "apple" #=> false, should be true :apple.hash == "apple".hash #=> false, should be true {apples: 10}["apples"] #=> nil, should be 10 {"apples" => 10}[:apples] #=> nil, should be 10 :apple.object_id == "apple".object_id #=> false, but that's actually fine All it would take to make the next generation of Rubyists less confused is this: class Symbol < String def initialize *args super self.freeze end (and a lot of other library-level hacking, but still, not too complicated) See also: http://onestepback.org/index.cgi/Tech/Ruby/SymbolsAreNotImmutableStrings.red http://www.randomhacks.net/articles/2007/01/20/13-ways-of-looking-at-a-ruby-symbol Why does my code break when using a hash symbol, instead of a hash string? Why use symbols as hash keys in Ruby? What are symbols and how do we use them? Ruby Symbols vs Strings in Hashes Can't get the hang of symbols in Ruby

  Read the article

• Getting auth token for dropbox account from accountmanager in android

  - by user1490880

  I am trying to get auth token for a dropbox account configured in device from account manager. I am using accountManager.getAuthToken(account, "DROPBOX",null,Hello.this, new GetAuthTokenCallback(), null);//account" is dropbox account I am seeing a Allow/Deny page. I click on Allow, but the callback is not getting invoked at all and i dont get the auth token. I got the authtoken for a google account with this(with a different authtokentype). What i am missing. I am not sure about the authTokenType parameter for dropbox. Also are there any other parameter specific for dropbox like the bundle parameter that i am missing. Is this way possible for dropbox? Check below for the function parameters public AccountManagerFuture<Bundle> getAuthToken (Account account, String authTokenType, Bundle options, Activity activity, AccountManagerCallback<Bundle> callback, Handler handler) Link: http://developer.android.com/reference/android/accounts/AccountManager.html UPDATE I assume since we are able to create a dropbox account in android Accounts and Sync(Settings), there must be a dropbox authenticator that has all the functions in AbstractAccountAuthenticator implemented including getAuthToken(). So dropbox should support giving auth token i think. Also dropbox uses oauth1, whereas account manager uses outh 2.0. So is this an issue.Can anyone comment on this?

  Read the article

• Can I add a condition to CakePHP's update statement?

  - by Don Kirkby

  Since there doesn't seem to be any support for optimistic locking in CakePHP, I'm taking a stab at building a behaviour that implements it. After a little research into behaviours, I think I could run a query in the beforeSave event to check that the version field hasn't changed. However, I'd rather implement the check by changing the update statement's WHERE clause from WHERE id = ? to WHERE id = ? and version = ? This way I don't have to worry about other requests changing the database record between the time I read the version and the time I execute the update. It also means I can do one database call instead of two. I can see that the DboSource.update() method supports conditions, but Model.save() never passes any conditions to it. It seems like I have a couple of options: Do the check in beforeSave() and live with the fact that it's not bulletproof. Hack my local copy of CakePHP to check for a conditions key in the options array of Model.save() and pass it along to the DboSource.update() method. Right now, I'm leaning in favour of the second option, but that means I can't share my behaviour with other users unless they apply my hack to their framework. Have I missed an easier option?

  Read the article

• Generating easy-to-remember random identifiers

  - by Carl Seleborg

  Hi all, As all developers do, we constantly deal with some kind of identifiers as part of our daily work. Most of the time, it's about bugs or support tickets. Our software, upon detecting a bug, creates a package that has a name formatted from a timestamp and a version number, which is a cheap way of creating reasonably unique identifiers to avoid mixing packages up. Example: "Bug Report 20101214 174856 6.4b2". My brain just isn't that good at remembering numbers. What I would love to have is a simple way of generating alpha-numeric identifiers that are easy to remember. Examples would be "azil3", "ulmops", "fel2way", etc. I just made these up, but they are much easier to recognize when you see many of them at once. I know of algorithms that perform trigram analysis on text (say you feed them a whole book in German) and that can generate strings that look and feel like German words. This requires lots of data, though, and makes it slightly less suitable for embedding in an application just for this purpose. Do you know of anything else? Thanks! Carl

  Read the article

• C#'s equivalent to VB.Net's DirectCast?

  - by Collin Sauve

  This has probably been asked before, but if it has, I can't find it. Does C# have an equivalent to VB.Net's DirectCast? I am aware that it has () casts and the 'as' keyword, but those line up to CType and TryCast. To be clear, these keywords do the following; CType/() casts: If it is already the correct type, cast it, otherwise look for a type converter and invoke it. If no type converter is found, throw an InvalidCastException. TryCast/"as" keyword: If it is the correct type, cast it, otherwise return null. DirectCast: If it is the correct type, cast it, otherwise throw an InvalidCastException. EDIT: After I have spelled out the above, some people have still responded that () is equivalent, so I will expand further upon why this is not true. DirectCast only allows for either Narrowing or Widening conversions on inheritance tree, it does not support conversions across different branches like () does. ie: C#, this compiles and runs: //This code uses a type converter to go across an inheritance tree double d = 10; int i = (int)d; VB.Net, this does NOT COMPILE 'Direct cast can only go up or down a branch, never across to a different one. Dim d as Double= 10 Dim i as Integer = DirectCast(d, Integer) The equivalent in VB.Net to my C# code is CType: 'This compiles and runs Dim d as Double= 10 Dim i as Integer = CType(d, Integer) (Edit again, I was originally using strings, I changed it to double... sorry)

  Read the article

• what is the point of heterogenous arrays?

  - by aharon

  I know that more-dynamic-than-Java languages, like Python and Ruby, often allow you to place objects of mixed types in arrays, like so: ["hello", 120, ["world"]] What I don't understand is why you would ever use a feature like this. If I want to store heterogenous data in Java, I'll usually create an object for it. For example, say a User has int ID and String name. While I see that in Python/Ruby/PHP you could do something like this: [["John Smith", 000], ["Smith John", 001], ...] this seems a bit less safe/OO than creating a class User with attributes ID and name and then having your array: [<User: name="John Smith", id=000>, <User: name="Smith John", id=001>, ...] where those <User ...> things represent User objects. Is there reason to use the former over the latter in languages that support it? Or is there some bigger reason to use heterogenous arrays? N.B. I am not talking about arrays that include different objects that all implement the same interface or inherit from the same parent, e.g.: class Square extends Shape class Triangle extends Shape [new Square(), new Triangle()] because that is, to the programmer at least, still a homogenous array as you'll be doing the same thing with each shape (e.g., calling the draw() method), only the methods commonly defined between the two.

  Read the article

• Go for Zend framework or Django for a modular web application?

  - by dr. squid

  I am using both Zend framework and Django, and they both have they strengths and weakness, but they are both good framworks in their own way. I do want to create a highly modular web application, like this example: modules: Admin cms articles sections ... ... ... I also want all modules to be self contained with all confid and template files. I have been looking into a way to solve this is zend the last days, but adding one omer level to the module setup doesn't feel right. I am sure this could be done, but should I? I have also included Doctrine to my zend application that could give me even more problems in my module setup! When we are talking about Django this is easy to implement (Easy as in concept, not in implementation time or whatever) and a great way to create web apps. But one of the downsides of Django is the web hosing part. There are some web hosts offering Django support, but not that many.. So then I guess the question is what have the most value; rapid modular development versus hosting options! Well, comments are welcome! Thanks

  Read the article

• QT QSslError being signaled with the error code set to NoError

  - by Nantucket

  My Problem I compiled OpenSSL into QT to enable OpenSSL support. Everything appeared to go correctly in the compile. However, when I try to use the official HTTP example application that can be found here, everytime I try to download an https page, it will signal two QSslError, each with contents NoError. The types of QSslErrors, including NoError, are documented here, poorly. There is no explanation on why they even included an error type called NoError, or what it means. Bizarrely, the NoError error code seems to be true, as it downloads the remote https document perfectly even while signaling the error. Does anyone have any idea what this means and what could possibly be causing it? Optional Background Reading Here is the relevant part of the code from the example app (this is connected to the network connection's sslErrors signal by the constructor): void HttpWindow::sslErrors(QNetworkReply*,const QList<QSslError> &errors) { QString errorString; foreach (const QSslError &error, errors) { if (!errorString.isEmpty()) errorString += ", "; errorString += error.errorString(); } if (QMessageBox::warning(this, tr("HTTP"), tr("One or more SSL errors has occurred: %1").arg(errorString), QMessageBox::Ignore | QMessageBox::Abort) == QMessageBox::Ignore) { reply->ignoreSslErrors(); } } I have tried the old version of this example, and it produced the same result. I have tried OpenSSL 1.0.0a and 0.9.8o. I have tried tried compiling OpenSSL myself, I have tried using pre-compiled versions of OpenSSL from the net. All produce the same result. If this were my first time using QT with SSL, I would almost think this is the intended result (even though their example application is popping up error warning message windows), if not for the fact that last time I played with QT, using what would now be an old version of QT with an old version of SSL, I distinctly remember everything working fine with no error windows. My system is running Windows 7 x64.

  Read the article

• How to convert source code to a xml based representation of the ast?

  - by autobiographer

  i wanna get a xml representation of the ast of java and c code. 3 months ago, i asked this question yet but the solutions weren't comfortable for me srcml seems to be a good solution for this problem but it does not support line numbers and columns but i need that feature. about elsa: cite: "There is ongoing effort to export the Elsa AST as an XML document; we expect to be able to advertise this in the next public release." dms... didn't understand that. especially for java, there is javaml which supports line numbers. but the sourceforge page doesn't list any files. question: there's software available which supports conversion of ast into xml which supports line numbers (and columns) [especially for java and c/c++]? is there an alternative to javaml and srcml? ps: i don't wanne have parser generators. i hope to find a tool which can be used on the console typing: ./my-xml-generator Test.java [or something like that]... or a java implementation would be great too.

  Read the article

• Sending an email with browser capabilities and screen size etc.

  - by talkingnews

  A lot of my visitors are blind (with it being a site for the blind), and often when trying to diagnose problems, I'd like to know what version of browser etc they're using, whether flash is installed. Because more often than not, someone will swear they are using X, when in fact Y is installed. Currently, I'm using http://jsbrwsniff.sourceforge.net/usage.html piped into an email, but I've got 2 problems here: First of all, jsbrwsniff is quite "heavy" and hasn't been updated since early 2007, so there's a lot of -1's in the result. Secondly, if I call it as follows, the page reloads: <a href="#" onclick="sendEmail()">Email feedback</a> And if I call it like this, the page goes blank and looks like it's trying to infinitely load a blank page: <a href="javascript:sendEmail()">Email feedback</a> See the nightmare for yourself here: http://kingston.talking-newspapers.co.uk/ Now, I know there are 1001 articles and comments here and elsewhere saying "don't use browser sniffers, they can be spoofed (etc)", but honestly, you'll have to trust me that this is a significantly useful tool when you're talking someone in their more "senior years" and using a screenreader through "help about", when they've clicked the wrong window to start with! I'm using jquery anyway in the site, and I'm aware of $jQuery.browser and $jQuery.support, but these don't tell me the elements I need (like whether Flash is installed, and what version etc). I've looked everywhere for a jquery plugin for my needs, with no luck. Finally, if I have to stick to the current method of jsbrwsniff then it's not the end of the world, but if anyone knows a way of launching the user's email client populated with the information I need but WITHOUT refreshing or blanking the page, I'd love to know. BTW - there's a good reason for not using a webform, which is simply because it's easier for the screen-reader user to use an email client they are used to. Thanks!

  Read the article

• C headers: compiler specific vs library specific?

  - by leonbloy

  Is there some clear-cut distinction between standard C *.h header files that are provided by the C compiler, as oppossed to those which are provided by a standard C library? Is there some list, or some standard locations? Motivation: int this answer I got a while ago, regarding a missing unistd.h in the latest TinyC compiler, the author argued that unistd.h (contrarily to sys/unistd.h) should not be provided by the compiler but by your C library. I could not make much sense of that response (for one thing shouldn't that also apply to, say, stdio.h?) but I'm still wondering about it. Is that correct? Where is some authoritative reference for this? Looking in other compilers, I see that other "self contained" POSIX C compilers that are hosted in Windows (like the GCC toolchain that comes with MinGW, in several incarnations; or Digital Mars compiler), include all header files. And in a standard Linux distribution (say, Centos 5.10) I see that the gcc package provides a few header files (eg, stdbool.h, syslimits.h) in /usr/lib/gcc/i386-redhat-linux/4.1.1/include/, and the glibc-headers package provides the majority of the headers in /usr/include/ (including stdio.h, /usr/include/unistd.h and /usr/include/sys/unistd.h). So, in neither case I see support for the above claim.

  Read the article

• Is it possible to use SqlGeography with Linq to Sql?

  - by cofiem

  I've been having quite a few problems trying to use Microsoft.SqlServer.Types.SqlGeography. I know full well that support for this in Ling to Sql is not great. I've tried numerous ways, beginning with what would the expected way (Database type of geography, CLR type of SqlGeography). This produces the NotSupportedException, which is widely discussed via blogs. I've then gone down the path of treating the geography column as a varbinary(max), as geography is a UDT stored as binary. This seems to work fine (with some binary reading and writing extension methods). However, I'm now running into a rather obscure issue, which does not seem to have happened to many other people. System.InvalidCastException: Unable to cast object of type 'Microsoft.SqlServer.Types.SqlGeography' to type 'System.Byte[]'. This error is thrown from an ObjectMaterializer when iterating through a query. It seems to only occur when the tables containing geography columns are included in a query implicitly (ie. using the EntityRef<> properties to do joins). System.Data.Linq.SqlClient.ObjectReaderCompiler.ObjectReader`2.MoveNext() My question: If I'm retrieving the geography column as varbinary(max), I might expect the reverse error: can't cast byte[] to SqlGeography. That I would understand. This I don't. I do have some properies on the partial LINQ to SQL classes that hide the binary conversion... could those be the issue? Any help appreciated, and I know there's probably not enough information.

  Read the article

< Previous Page | 800 801 802 803 804 805 806 807 808 809 810 811  | Next Page >