Search Results

Search found 5843 results on 234 pages for 'material handling equipme'.

Page 25/234 | < Previous Page | 21 22 23 24 25 26 27 28 29 30 31 32  | Next Page >

• java serial I/O: handling USB serial connection/disconnection in a robust manner

  - by Jason S

  I'm using rxtx for serial I/O handling in Java with an FTDI2232H that provides a USB comm port. It works great, with one exception: if I unplug the USB cable, so that the COM port disappears at runtime, it spews exceptions left and right: java.io.IOException: No error in nativeavailable at gnu.io.RXTXPort.nativeavailable(Native Method) at gnu.io.RXTXPort$SerialInputStream.read(RXTXPort.java:1427) at gnu.io.RXTXPort$SerialInputStream.read(RXTXPort.java:1339) and when I re-plug the cable in again, it does not recover. Is there any way to get rxtx to work properly with USB comm port connection/disconnection? (I've tried to post to the rxtx mailing list but for some strange reason I cannot send messages even though I am subscribed to the list. I've emailed the list admin and have gotten no response.) If not, is there another serial I/O framework that does?

  Read the article

• Logging exceptions in WCF with IErrorHandler inside HandleError or ProvideFault?

  - by Dannerbo

  I'm using IErrorHandler to do exception handling in WCF and now I want to log the exceptions, along with the stack trace and the user that caused the exception. I've read everywhere to put the logging in the HandleError method, and not the ProvideFault method. My question is, why? The only way I can see to get the user that caused the exception is: OperationContext.Current.IncomingMessageProperties.Security.ServiceSecurityContext.PrimaryIdentity ...But this only seems to work inside ProvideFault, and not inside HandleError. Is there a way to get the user inside HandleError?

  Read the article

• Inclusion Handling in MVC 2 / MVCContrib

  - by mnemosyn

  I'd like to improve my page by combining and minifying javascript and CSS files. Since MVCContrib already contains a project called IncludeHandling, I took a look at that which unfortunately left me with unanswered questions: There is quite a set of interfaces and objects involved in the process. Now I'm using Ninject.Mvc, but it seems that MvcContrib.IncludeHandling is using some additional (home-brewed?) DI? Can I work around this? Has anybody used this and can share some experiences? Secondly, advice that is often heard is to put static content on different domains so the request does not contain cookies and the like, making it much easier for the server to handle the request. But how can I combine this with automatic inclusion handling - isn't that necessarily served in the same application? EDIT: Figured that there is really just a single resolve call in the whole thing, i really wonder why they use DI for that... Thinking about a fork there...

  Read the article

• NULL handling with subselect in Hibernate Criteria API

  - by Jens Schauder

  I'm constructing a Hibernate Criterion, using a subselect as follows DetachedCriteria subselect = DetachedCriteria.forClass(NhmCode.class, "sub"); // the subselect selecting the maximum 'validFrom' subselect.add(Restrictions.le("validFrom", new Date())); // it should be in the past (null needs handling here) subselect.add(Property.forName("sub.lifeCycle").eqProperty("this.id")); // join to owning entity subselect.setProjection(Projections.max("validFrom")); // we are only interested in the maximum validFrom Conjunction resultCriterion = Restrictions.conjunction(); resultCriterion.add(Restrictions.ilike(property, value)); // I have other Restrictions as well resultCriterion.add(Property.forName("validFrom").eq(subselect)); // this fails when validFrom and the subselect return NULL return resultCriterion; It works ok so far, but the restriction on the last line before the return statement is false when validFrom and subselect result in NULL. What I need is a version which handles this case as true. Possibly by applying a NVL or coalesce or similar. How do I do this?

  Read the article

• Handling User Authentication in C#.NET?

  - by Daniel

  I am new to .NET, and don't have much experience in programming. What is the standard way of handling user authentication in .NET in the following situation? 1.In Process A, User inputs ID/Password 2.Process A sends the ID/Password to Process B over a nonsecure public channel. 3.Process B authenticates the user with the recieved ID/Password what are some of the standard cryptographic algorithms I can use in above model? The users(customers that bought my company's software) will be running the software(Process A) locally in their computer(connected to internet). I need to authenticate the users so that only registered users can run the program. Thank You!

  Read the article

• iphone/ipad orientation handling

  - by Mark

  This is more of a general question for people to provide me guidance on, basically Im learning iPad/iPhone development and have finally come across the multi-orientation support question. I have looked up a fair amount of doco, and my book "Beginning iPhone 3 Development" has a nice chapter on it. But my question is this, if I was to programatically change my controls (or even use different views for each orientation) how on earth to people maintain their code base? I can just imagine so many issues with spaghetti code/thousands of "if" checks all over the place, that it would drive me nuts to make one small change to the UI arrangement. Does anyone have experience handling this issue? What is a nice way to control it? Thanks a lot Mark

  Read the article

• Trapping errors in TClientDataSet.CommandText

  - by Rob McDonell

  I have a TClientDataSet connected to a TDataSetProvider, which in turn is connected to a TAdsTable. I set the SQL command and then open the ClientDataset something like this: try CDS.CommandText := 'SELECT * FROM tablename WHERE fieldname = 1'; CDS.Open except // trap exception here - this never gets executed! end; If the SQL statement in CommandText fails, however (syntax error or whatever) I get an exception within the Advantage code, but it never gets caught in my own exception handling code. Is there any way for me to trap this error and report it nicely to the user. Alternatively is there a way to verify the syntax of an SQL query before executing it? I'm using Delphi Pro 2009, and Advantage Local Server 9.

  Read the article

• Should Java IOException have been an unchecked RuntimeException?

  - by Derek Mahar

  Do you agree that the designers of Java class java.io.IOException should have made it an unchecked run-time exception derived from java.lang.RuntimeException instead of a checked exception derived only from java.lang.Exception? I think that class IOException should have been an unchecked exception because there is little that an application can do to resolve problems like file system errors. However, in When You Can't Throw An Exception, Elliotte Rusty Harold claims that most I/O errors are transient and so you can retry an I/O operation several times before giving up: For instance, an IOComparator might not take an I/O error lying down, but — because many I/O problems are transient — you can retry a few times, as shown in Listing 7: Is this generally the case? Can a Java application correct I/O errors or wait for the system to recover? If so, then it is reasonable for IOException to be checked, but if it is not the case, then IOException should be unchecked so that business logic can delegate handling this exception to a separate system error handler.

  Read the article

• How to secure Java webservices with login and session handling

  - by hubertg

  I'd like to secure my (Java metro) webservice with a login. Here's how I'm planning to do that: Steps required when calling a webservice method are: call login(user,pwd), receive a session token 1.1 remember the token call servicemethod (token, arg1, arg2...) webservice checks if the token is known, if not throw exception otherwise proceed logout or timeout after x time periods of inactivity my questions: 1. what's your opinion on this approach? does it make sense? 2. are there any libraries which take the burden of writing a session handling (maybe with database persistence to survive app restarts) (the solution should be simple and easily usable with Java and .NET clients) thanks!

  Read the article

• Looking for an automated logging tool/library for .NET!

  - by tsocks

  Hello, I'm looking for an library/tool for .NET that logs almost everything that happens in my C# application (Windows Form). The problem is that I'm delivering an application to a client (Windows XP) and after doing some task, that classic Microsoft error window appears: "ApplicationName has encountered a problem and needs to close. We are sorry for the inconvenience" I'm currently handling my application exceptions, but this is something external and I can't get anything from that error, so I would like any automated library that helps me with that. It would work if it logs each line of code executed, orr just log what line was executing before that error appeared, or something that could give me more info about that error. Thank you! P.S: It's a multithreaded application, and have to Timer controls (one for watching a folder every 5secs, and another for watching thread list...). I'm using Windows 7 here and everything seems to work ok.

  Read the article

• Handling events exposed on a .NET class via COM in VB6

  - by PeanutPower

  Handling events exposed on a .NET class via COM in VB6 My test .NET (class libary registered for interop in compiler settings) code: Imports System.Runtime.InteropServices <InterfaceType(ComInterfaceType.InterfaceIsIDispatch), ComVisible(True)> _ Public Interface MyEventInterface <DispId(1)> Event Exploded(ByVal Text As String) <DispId(2)> Sub PushRedButton() End Interface <ClassInterface(ClassInterfaceType.None)> _ Public Class EventTest Implements MyEventInterface Public Event Exploded(ByVal Text As String) Implements MyEventInterface.Exploded Public Sub PushRedButton() Implements MyEventInterface.PushRedButton RaiseEvent Exploded("Bang") End Sub End Class My test VB6 application winforms code (which references the above class libary): Public ct As New ComTest1.EventTest Private Sub Command1_Click() ct.add_Exploded (ExplodedHandler) ct.PushRedButton ct.remove_Exploded (ExplodedHandler) End Sub Private Sub ExplodedHandler(ByVal Text As String) MsgBox Text End Sub Specifially I'm not sure how to set up the handler in VB6 the compile error I get is "Argument not optional" on this line in the VB6: ct.add_Exploded (ExplodedHandler)

  Read the article

• IntelliSense based snippet handling with Visual Studio 2010 SDK MEF Based text editor

  - by Nicolai Ustinov

  Using the new Visual Studio 2010 SDK developing against the MEF based editor structure there's a question: How can I use the MEF editor interfaces to handle snippet behavior in IntelliSense? The ICompletionSession itself is not a problem (e.g. get the available snippets) rather filling the snippet, handling the subsequently expected actions like tab, enter behavior, text replacement, etc. Is there any way to do that without a language service? Checking the built-in behavior in Visual Studio base editor implementation they built the MEF interfaces on top of a set of language service based objects.

  Read the article

• Programming an Event listener for files in a directory on Linux

  - by Epitaph

  On Ubuntu linux, when you watch a flash video, it gets saved temporarily in the /tmp as flv files while the video buffers. I use vlc to directly play these files. Currently, I have scripted a shortcut that directly scans and opens the latest file in /tmp with vlc, when clicked. But, I want to program a Java application that will continually monitor this /tmp directory for any new flv files, and open it in vlc automatically. I know I can use Runtime.exec() to open the VLC application with the flv files. But, I DO NOT want to run a while(true) loop (with sleep) to scan for files. How can I make use of Event Handling (Java or any other language) on Linux to complete this task?

  Read the article

• Catch database exception in Kohana

  - by danilo

  I'm using Kohana 2. I would like to catch a database exception to prevent an error page when no connection to the server can be established. The error displayed is system/libraries/drivers/Database/Mysql.php [61]: mysql_connect() [function.mysql-connect]: Lost connection to MySQL server at 'reading initial communication packet', system error: 110 The database server is not reachable at all at this point. I'm doing this from a model. I tried both public function __construct() { // load database library into $this->db try { parent::__construct(); } catch (Exception $e) { die('Database error occured'); } } as well as try { $hoststatus = $this->db->query('SELECT x FROM y WHERE z;'); } catch (Exception $e) { die('Database error occured'); } ...but none of them seemed to work. It seems as if no exception gets passed on from the main model. Is there another way to catch the database error and use my own error handling?

  Read the article

• Call up last exception on an ASP.NET error page.

  - by Aren B

  I've got an error page here SiteError.aspx and it's configured correctly in the web.config to go there when unhandled exceptions are encountered. I want to use this page to log the exception that triggered it as well because I only want to LOG the errors that the users encounter (i.e. if SiteError.aspx is ever hit.) This is the code I Have: In the OnLoad(...) in SiteError.aspx Exception lastEx = Context.Server.GetLastError(); if (lastEx != null) log.Error("A site error was encountered", lastEx); However, my log is never showing up in my Output, and If i breakpoint on line 2 (in this example) code execution is never interupted (after letting the exception clear to ASP.NET handling in the debugger.

  Read the article

• WPF exception handling when launched from WinForms

  - by Sonic Soul

  so i came across this interesting article on WPF exception handling: http://srtsolutions.com/public/item/251263 it works by declaring DispatcherUnhandledException handler in xaml <application> node. but what if a WPF window is launched from win forms application? where can i declare a general exception handler? The problem is that when WPF crashes, it brings down the whole WinForms app with it. *Edit what if instead of launching the WPF window directly, i launched an "Application" which than defined a start window?? is that possible/advisable?

  Read the article

• Strategy for unsubscribing event handlers

  - by stiank81

  In my WPF application I have a View that is given a ViewModel, and when given this View it adds event handlers to the ViewModel's PropertyChanged event. When some action occur in the GUI I remove the View and add another View to the holding container - where this new one is bound to the same ViewModel. After this has happened the old View still keeps handling PropertyChanged events in the ViewModel. I'm assuming this happens because the View hasn't been collected by the Garbage Collector yet, and therefore is alive? Well - I need it to stop. My assumption is that I need to manually detach the event handler from the ViewModel? Is there a best-practice on how to handle this?

  Read the article

• Handling wm_mousewheel message in WTL

  - by Rushi

  I am trying to handle wm_mousewheel for my application. Code: BEGIN_MSG_MAP(DxWindow) MESSAGE_HANDLER(WM_MOUSEWHEEL, KeyHandler) END_MSG_MAP() . . . LRESULT DxWindow::KeyHandler( UINT uMsg, WPARAM wParam, LPARAM lParam, BOOL &bHandled ) { if(uMsg==wm_mousewheel) { //Perform task. } return 0; } But this code doesn't work.KeyHandler doesn't receive wm_mousewheel message. I am testing this application on vista. If my approach is wrong how to handle wm_mousewheel properly? Do vista is responsible for failure in handling wm_mousewheel message?

  Read the article

• How to identify the source of a text selection event coming from a CompareEditorInput in eclipse?

  - by tangens

  In my eclipse plugin I have the following code: public class MyHandler extends AbstractHandler { @Override public Object execute( ExecutionEvent event ) throws ExecutionException { ISelection sel = HandlerUtil .getActiveWorkbenchWindowChecked( event ) .getSelectionService() .getSelection(); if( sel instanceof TextSelection ) { IEditorPart activeEditor = PlatformUI .getWorkbench() .getActiveWorkbenchWindow() .getActivePage() .getActiveEditor(); IEditorInput editorInput = activeEditor.getEditorInput(); if( editorInput instanceof CompareEditorInput ) { // here are two possible sources of the text selection, the // left or the right side of the compare editor. // How can I find out, which side it is from? } } return null; } } Here I'm handling a text selection event coming from an CompareEditorInput, i.e. the result of comparing two remote revisions of a file with subclipse. Now I want to handle the text selection properly. For that I have to know if it selects some text inside the left side editor or inside the right side editor. How can I find that out?

  Read the article

• When is a C++ terminate handler the Right Thing(TM)?

  - by Joseph Garvin

  The C++ standard provides the std::set_terminate function which lets you specify what function std::terminate should actually call. std::terminate should only get called in dire circumstances, and sure enough the situations the standard describes for when it's called are dire (e.g. an uncaught exception). When std::terminate does get called the situation seems analagous to being out of memory -- there's not really much you can sensically do. I've read that it can be used to make sure resources are freed -- but for the majority of resources this should be handled automatically by the OS when the process exits (e.g. file handles). Theoretically I can see a case for if say, you needed to send a server a specific message when exiting due to a crash. But the majority of the time the OS handling should be sufficient. When is using a terminate handler the Right Thing(TM)? Update: People interested in what can be done with custom terminate handlers might find this non-portable trick useful.

  Read the article

• Silverlight error-handling conventions: There is no relationship between onSilverlightError and Repo

  - by rasx

  When I see the call System.Windows.Browser.HtmlPage.Window.Eval (which is evil) in ReportErrorToDOM (in App.xaml.cs) this shows me that it has no relationship to onSilverlightError. So what kind of JavaScript-based scenario calls onSilverlightError? When will onSilverlightError definitely be needed? What are Silverlight error-handling conventions in general? This is a very important comment by Erik Monk but needs more detail: There are 2 kinds of terminal errors in Silverlight. 1) Managed errors (hit the managed Application_UnhandledException method). Note that some errors may not even get to this point. If the managed infrastructure can't be loaded for some reason (out of memory error maybe...), you won't get this kind of error. Still, if you can get it, you can use a web service (or the CLOG project) to communicate it back to the server. 2) Javascript errors.

  Read the article

• MS-Access VBA: form_error vs on error

  - by dmr

  I am trying to set up error handling for a MS-Access application. The standard method to do this seems to be with an On Error statement in each subroutine/function. It seems simpler to me to use the Form_Error function to catch all the runtime errors in that form as opposed to an On Error statement for each sub/function called by an event on that form. (Obviously, for code in modules, there is no Form_Error function and therefore the only method is the On Error statement) What are the pros and cons of using On Error vs Form_Error?

  Read the article

• Please advise on handling the existing geek

  - by ranja

  Quick Story: I started a new job where everyone funneled their questions to 'the geek'. Being an experienced developer, I can do most of my assignments without consultation with the geek - thinks such as how to select the top 10 rows in a table. Question: Is there a preferred way of handling these cases without offending the existing geek while ensuring the best solution gets implemented? My issue is the the existing geek is very young and makes a lot of mistakes, but still sounds authoritative because the other coders are just out of school and don't know better.

  Read the article

• WCF Business logic handling

  - by Raj

  I have a WCF service that supports about 10 contracts, we have been supporting a client with all the business rules specific to this client now we have another client who will be using the exact same contracts (so we cannot change that) they will be calling the service exactly the same way the previous client called now the only way we can differentiate between the two clients is by one of the input parameters. Based on this input parameter we have to use a slightly different business logic – the logic for both the Client will be same 50% of the time the remainder will have different logic (across Business / DAL layers) . I don’t want to use if else statement in each of contract implementation to differentiate and reroute the logic also what if another client comes in. Is there a clean way of handling a situation like this. I am using framework 3.5. Like I said I cannot change any of the contracts (service / data contract ) or the current service calling infrastructure for the new client. Thanks

  Read the article

• Exception handling in Boost.Asio

  - by Alex B

  Boost.Asio documentation suggests the following exception handling pattern: boost::asio::io_service io_service; ... for (;;) { try { io_service.run(); break; // run() exited normally } catch (my_exception& e) { // Deal with exception as appropriate. } } The problem with it is that the context of exception is lost at the point when it's handled. For example, if I have multiple socket sessions going on, I don't know which one caused the exception to be thrown. What would be a better way to handle the exceptions from asynchronous handlers without wrapping them in try/catch blocks?

  Read the article

< Previous Page | 21 22 23 24 25 26 27 28 29 30 31 32  | Next Page >