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  • Thread to receive the messages from serial port is not working using c#

    - by karthik
    I am using Serial port to receive the messages. The below function is running in a thread. When i debug i find that the thread is running properly. But "if (sp.IsOpen)" is always false, due to which the code is not executing inside the IF condition at all. It says the Port is closed. I will be having multiple serial ports in my system and i will not know, which port will receive the message. So i need to listen to all the ports in one Thread. How can i solve my problem here ? private void ListenerPorts() { log.Info("Listening Thread Started"); while (true) { //foreach (SerialPort sp in storeport) foreach (SerialPort sp in comPortsList) { if (sp.IsOpen) { sp.ReadTimeout = readTimeoutInMs; sp.WriteTimeout = writeTimeoutInMs; try { string msg = sp.ReadLine(); this.GetMessageRichTextBox("Message : " + msg + "\n"); sp.WriteLine(sp.PortName); if (msg.Contains("COM")) { // is AutoScan receiverPortName = sp.ReadLine(); this.updateLblStatusRichTextBox(sp.PortName + " is connected to " + msg + "\n"); } else { //standalone is uppercase ReceiverPortName = sp.ReadLine(); this.updateLblStatusRichTextBox(sp.PortName + " is connected to " + ReceiverPortName + "\n"); } } catch (Exception ex) { // no data System.Diagnostics.Debug.WriteLine(sp.PortName + " : " + ex.Message); } } } } }

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  • Struts 2 how to display messages saved in a Interceptor which would redirec to another action?

    - by mui13
    in my interceptor, if user doesn't have enough right, there would be a warn message: public String intercept(ActionInvocation invocation) throws Exception { ActionContext actionContext = invocation.getInvocationContext(); Map<String, Object> sessionMap = actionContext.getSession(); User loginUser = (User) sessionMap.get("user"); Object action = invocation.getAction(); if (loginUser != null && loginUser.getRole().getId() != Constant.AUTHORITY_ADMIN) { ((ValidationAware) action).addFieldError("user.authority", ((DefaultAction) action).getText("user.action.authority.not.enough")); return DefaultAction.HOME_PAGE; } return invocation.invoke(); } then, it would redirect to "HOME_PAGE" action, if success, display information in the jsp. So how to display the warn message? i have used two interceptors configed in strust.xml, for admin right requirment: <interceptor-stack name="authorityStack"> <interceptor-ref name="authority" /> <interceptor-ref name="defaultStack" /> <interceptor-ref name="store"> <param name="operationMode">STORE</param> </interceptor-ref> </interceptor-stack> default is: <interceptor-stack name="default"> <interceptor-ref name="login" /> <interceptor-ref name="defaultStack" /> <interceptor-ref name="store"> <param name="operationMode">AUTOMATIC</param> </interceptor-ref> </interceptor-stack>

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  • Is my method for avoiding dynamic_cast<> faster than dynamic_cast<> itself ?

    - by ereOn
    Hi, I was answering a question a few minutes ago and it raised to me another one: In one of my projects, I do some network message parsing. The messages are in the form of: [1 byte message type][2 bytes payload length][x bytes payload] The format and content of the payload are determined by the message type. I have a class hierarchy, based on a common class Message. To instanciate my messages, i have a static parsing method which gives back a Message* depending on the message type byte. Something like: Message* parse(const char* frame) { // This is sample code, in real life I obviously check that the buffer // is not NULL, and the size, and so on. switch(frame[0]) { case 0x01: return new FooMessage(); case 0x02: return new BarMessage(); } // Throw an exception here because the mesage type is unknown. } I sometimes need to access the methods of the subclasses. Since my network message handling must be fast, I decived to avoid dynamic_cast<> and I added a method to the base Message class that gives back the message type. Depending on this return value, I use a static_cast<> to the right child type instead. I did this mainly because I was told once that dynamic_cast<> was slow. However, I don't know exactly what it really does and how slow it is, thus, my method might be as just as slow (or slower) but far more complicated. What do you guys think of this design ? Is it common ? Is it really faster than using dynamic_cast<> ? Any detailed explanation of what happen under the hood when one use dynamic_cast<> is welcome !

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  • What is the scope of TRANSACTION in Sql server

    - by Shantanu Gupta
    I was creating a stored procedure and i got stuck in the writing methodology of me and my collegue. I am using SQL Server 2005 I was writing Stored procedure like this BEGIN TRAN BEGIN TRY INSERT INTO Tags.tblTopic (Topic, TopicCode, Description) VALUES(@Topic, @TopicCode, @Description) INSERT INTO Tags.tblSubjectTopic (SubjectId, TopicId) VALUES(@SubjectId, @@IDENTITY) COMMIT TRAN END TRY BEGIN CATCH DECLARE @Error VARCHAR(1000) SET @Error= 'ERROR NO : '+ERROR_NUMBER() + ', LINE NO : '+ ERROR_LINE() + ', ERROR MESSAGE : '+ERROR_MESSAGE() PRINT @Error ROLLBACK TRAN END CATCH And my collegue was writing it like the below one BEGIN TRY BEGIN TRAN INSERT INTO Tags.tblTopic (Topic, TopicCode, Description) VALUES(@Topic, @TopicCode, @Description) INSERT INTO Tags.tblSubjectTopic (SubjectId, TopicId) VALUES(@SubjectId, @@IDENTITY) COMMIT TRAN END TRY BEGIN CATCH DECLARE @Error VARCHAR(1000) SET @Error= 'ERROR NO : '+ERROR_NUMBER() + ', LINE NO : '+ ERROR_LINE() + ', ERROR MESSAGE : '+ERROR_MESSAGE() PRINT @Error ROLLBACK TRAN END CATCH Here the only difference that you will find is the position of writing Begin TRAN. According to me the methodology of my collegue should not work when an exception occurs i.e. Rollback should not get executed because TRAN does'nt have scope. But when i tried to run both the code, both was working in the same way. I am confused to know how does TRANSACTION works. Is it scope free or what ?

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  • Android, NetworkInfo.getTypeName(), NullpointerException

    - by moppel
    I have an activity which shows some List entries. When I click on a list item my app checks which connection type is available ("WIF" or "MOBILE"), through NetworkInfo.getTypeName(). As soon as I call this method I get a NullpointerException. Why? I tested this on the emulator, cause my phone is currently not available (it's broken...). I assume this is the problem? This is the only explanation that I have, if that's not the case I have no idea why this would be null. Here's some code snippet: public class VideoList extends ListActivity{ ... public void onCreate(Bundle bundle){ final ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); ... listview.setOnItemClickListener(new OnItemClickListener(){ public void onItemClick(AdapterView<?> parent, View view, int position, long id) { ... NetworkInfo ni = cm.getActiveNetworkInfo(); String connex = ni.getTypeName(); //Nullpointer exception here if(connex.equals("WIFI")doSomething(); } }); } }

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  • @PrePersist with entity inheritance

    - by gerry
    I'm having some problems with inheritance and the @PrePersist annotation. My source code looks like the following: _the 'base' class with the annotated updateDates() method: @javax.persistence.Entity @Inheritance(strategy = InheritanceType.TABLE_PER_CLASS) public class Base implements Serializable{ ... @Id @GeneratedValue protected Long id; ... @Column(nullable=false) @Temporal(TemporalType.TIMESTAMP) private Date creationDate; @Column(nullable=false) @Temporal(TemporalType.TIMESTAMP) private Date lastModificationDate; ... public Date getCreationDate() { return creationDate; } public void setCreationDate(Date creationDate) { this.creationDate = creationDate; } public Date getLastModificationDate() { return lastModificationDate; } public void setLastModificationDate(Date lastModificationDate) { this.lastModificationDate = lastModificationDate; } ... @PrePersist protected void updateDates() { if (creationDate == null) { creationDate = new Date(); } lastModificationDate = new Date(); } } _ now the 'Child' class that should inherit all methods "and annotations" from the base class: @javax.persistence.Entity @NamedQueries({ @NamedQuery(name=Sensor.QUERY_FIND_ALL, query="SELECT s FROM Sensor s") }) public class Sensor extends Entity { ... // additional attributes @Column(nullable=false) protected String value; ... // additional getters, setters ... } If I store/persist instances of the Base class to the database, everything works fine. The dates are getting updated. But now, if I want to persist a child instance, the database throws the following exception: MySQLIntegrityConstraintViolationException: Column 'CREATIONDATE' cannot be null So, in my opinion, this is caused because in Child the method "@PrePersist protected void updateDates()" is not called/invoked before persisting the instances to the database. What is wrong with my code?

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  • .NET multithreading, volatile and memory model

    - by fedor-serdukov
    Assume that we have the following code: class Program { static volatile bool flag1; static volatile bool flag2; static volatile int val; static void Main(string[] args) { for (int i = 0; i < 10000 * 10000; i++) { if (i % 500000 == 0) { Console.WriteLine("{0:#,0}",i); } flag1 = false; flag2 = false; val = 0; Parallel.Invoke(A1, A2); if (val == 0) throw new Exception(string.Format("{0:#,0}: {1}, {2}", i, flag1, flag2)); } } static void A1() { flag2 = true; if (flag1) val = 1; } static void A2() { flag1 = true; if (flag2) val = 2; } } } It's fault! The main quastion is Why... I suppose that CPU reorder operations with flag1 = true; and if(flag2) statement, but variables flag1 and flag2 marked as volatile fields...

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  • Why StrinUtils Apache class is not recognized in android?

    - by Maxood
    Why import org.apache.commons.lang.StringUtils cannot be imported in android by default. Do i have to include an external library? Then where can i find that library on the web? package com.myapps.urlencoding; import android.app.Activity; import org.apache.commons.lang.StringUtils; public class EncodeIdUtil extends Activity { /** Called when the activity is first created. */ private static Long multiplier=Long.parseLong("1zzzz",36); /** * Encodes the id. * @param id the id to encode * @return encoded string */ public static String encode(Long id) { return StringUtils.reverse(Long.toString((id*multiplier), 35)); } /** * Decodes the encoded id. * @param encodedId the encodedId to decode * @return the Id * @throws IllegalArgumentException if encodedId is not a validly encoded id. */ public static Long decode(String encodedId) throws IllegalArgumentException { long product; try { product = Long.parseLong(StringUtils.reverse(encodedId), 35); } catch (Exception e) { throw new IllegalArgumentException(); } if ( 0 != product % multiplier || product < 0) { throw new IllegalArgumentException(); } return product/multiplier; } }

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  • When to call Dispose in Entity Framework?

    - by Abdel Olakara
    Hi All, In my application I am making use of Spring.Net for IoC. The service objects are called from the ASP.Net files to perform CRUD operations using these service object. For example, I have CustomerService to do all CRUD operations on Customer table. I use entity framework and the entities are injected .. my question is where do I call the dispose method? As far as I understood from the API documentations, unless I call Dispose() there is no guaranty it will be garbage collected! So where and how do I do it? Example Service Class: public class CustomerService { public ecommEntities entities = {get; set;} public bool AddCustomer(Customer customer) { try { entities.AddToCustomer(customer); entities.SaveChanges(); return true; } catch (Exception e) { log.Error("Error occured during creation of new customer: " + e.Message + e.StackTrace); return false; } } public bool UpdateCustomer(Customer customer) { entities.SaveChanges(); return true; } public bool DeleteCustomer(Customer customer) . . . And I just create an object of CustomerService at the ASP partial class and call the necessary methods. Thanks in advance for the best practice and ideas.. Regards, Abdel Raoof

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  • How to sort HashSet() function data in sequence?

    - by vincent low
    I am new to Java, the function I would like to perform is to load a series of data from a file, into my hashSet() function. the problem is, I able to enter all the data in sequence, but I can't retrieve it out in sequence base on the account name in the file. Can anyone help? below is my code: public Set retrieveHistory(){ Set dataGroup = new HashSet(); try{ File file = new File("C:\\Documents and Settings\\vincent\\My Documents\\NetBeansProjects\\vincenttesting\\src\\vincenttesting\\vincenthistory.txt"); BufferedReader br = new BufferedReader(new FileReader(file)); String data = br.readLine(); while(data != null){ System.out.println("This is all the record:"+data); Customer cust = new Customer(); //break the data based on the , String array[] = data.split(","); cust.setCustomerName(array[0]); cust.setpassword(array[1]); cust.setlocation(array[2]); cust.setday(array[3]); cust.setmonth(array[4]); cust.setyear(array[5]); cust.setAmount(Double.parseDouble(array[6])); cust.settransaction(Double.parseDouble(array[7])); dataGroup.add(cust); //then proced to read next customer. data = br.readLine(); } br.close(); }catch(Exception e){ System.out.println("error" +e); } return dataGroup; } public static void main(String[] args) { FileReadDataModel fr = new FileReadDataModel(); Set customerGroup = fr.retrieveHistory(); System.out.println(e); for(Object obj : customerGroup){ Customer cust = (Customer)obj; System.out.println("Cust name :" +cust.getCustomerName()); System.out.println("Cust amount :" +cust.getAmount()); }

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  • Unable to change background colour for JOptionPane

    - by Sunil Kumar Sahoo
    Hi I have created sample progeam which will give same look and feel of a confirm dialog and set the background colour as red. But I donot know what is the problem that my background colour of option is displayed as the default colour but not red. also i need same look and feel of confirm dialog across all platforms. Here is the code that I have written. please help me to solve the issue public class JOptionPaneBackground { public static void main(String[] args) throws Exception { // UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName()); UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); UIDefaults uiDefaults = UIManager.getLookAndFeelDefaults(); List<Object> keys = new ArrayList<Object>(uiDefaults.keySet()); Collections.sort(keys, new Comparator<Object>() { public int compare(Object o1, Object o2) { return (o1.toString()).compareTo(o2.toString()); } }); for (Object key : keys) { System.out.println(String.format("%-40s = %s", key, uiDefaults.get(key))); } UIManager.put("OptionPane.background", Color.red); UIManager.put("Panel.background", Color.red); JOptionPane.showConfirmDialog(null, "Hello World!"); } }

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  • Servlet Mapping Help - Possible to Avoid Referencing Context Name?

    - by AJ
    Hi all, I am working on a Spring application and trying to get my URL mapping correct. What I would like to have work is the following: http://localhost:8080/idptest -> doesn't work But instead, I have to reference the context name in my URL in order to resolve the mapping: http://localhost:8080/<context_name>/idptest -> works How can I avoid the requirement of referencing the context name in my URL without using a rewrite/proxy engine e.g. Apache? Here is the servlet definition and mapping from my web.xml: <servlet> <servlet-name>idptest</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/conf/idptest.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>idptest</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> Here's the outline of my controller (showing annotations for request mappings): @Controller @RequestMapping("/idptest") public class MyController { @RequestMapping(method=RequestMethod.GET) public String setupForm(Model model){ MyObject someObject = new MyObject(); model.addAttribute("someObject", someObject); return "myform"; } @RequestMapping(method = RequestMethod.POST) public String processSubmit(@ModelAttribute("someObject") MyObject someObject) throws Exception { // POST logic... } } Thanks!

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  • ASP.NET, C#: timeout when trying to Transaction.Commit() to database; potential deadlock?

    - by user1843921
    I have a web page that has coding structured somewhat as follows: SqlConnection conX =new SqlConnection(blablabla); conX.Open(); SqlTransaction tran=conX.BeginTransaction(); try{ SqlCommand cmdInsert =new SqlCommand("INSERT INTO Table1(ColX,ColY) VALUES @x,@y",conX); cmdInsert.Transaction=tran; cmdInsert.ExecuteNonQuery(); SqlCommand cmdSelect=new SqlCOmmand("SELECT * FROM Table1",conX); cmdSelect.Transaction=tran; SqlDataReader dtr=cmdSelect.ExecuteReader(); //read stuff from dtr dtr.Close(); cmdInsert=new SqlCommand("UPDATE Table2 set ColA=@a",conX); cmdInsert.Transaction=tran; cmdInsert.ExecuteNonQuery(); //display MiscMessage tran.Commit(); //display SuccessMessage } catch(Exception x) { tran.Rollback(); //display x.Message } finally { conX.Close(); } So, everything seems to work until MiscMessage. Then, after a while (maybe 15-ish seconds?) x.Message pops up, saying that: "Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding." So something wrong with my trans.Commit()? The database is not updated so I assume the trans.Rollback works... I have read that deadlocks can cause timeouts...is this problem cause by my SELECT statement selecting from Table1, which is being used by the first INSERT statement? If so, what should I do? If that ain't the problem, what is?

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  • Problem with LINQ in C#

    - by David Bonnici
    I am encountering a problem when using LINQ in C#, I am constantly getting "Specified cast is not valid". This is what I am trying to do. I create a class in which I declare all the columns of the table. [Table(Name="tbl_Aff")] public class Affiliate { [Column] public string name; [Column] public string firstname; [Column] public string surname; [Column] public string title; } I then declare a strongly typed DataContext in which I declare all Table collections as members of the context. public partial class Database : DataContext { public Table affiliate; public Database() : base(Settings.getConnectionString()) { } //This method gets the connection string by reading from an XML file. } public partial class Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { Database database = new Database(); try { var q = from a in database.affiliate select a; foreach (var aff in q) // Here I get the error "Specified cast is not valid" { lblMessage.InnerHtml += aff.name + ""; } } catch (Exception ex) { System.Console.WriteLine(ex.Message); } } }

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  • Can someone please debug this Windows Azure Application?

    - by Vimvq1987
    Here's the myTODO project from codeplex: myTODO project I added any necessary libraries, added storage, changed obsolete types/methods, but everything went wrong when I debug it. An exception was thrown here (in TableStorage.cs): public IEnumerable<TElement> ExecuteWithRetries(RetryPolicy retry) { IEnumerable<TElement> ret = null; if (retry == null) { throw new ArgumentNullException("retry"); } retry(() => { try { ret = _query.Execute(); } catch (InvalidOperationException e) { if (TableStorageHelpers.CanBeRetried(e)) { throw new TableRetryWrapperException(e); } throw; } }); return ret; } I'm using Visual Studio 2008, SQL server 2008, Windows Azure SDK v1.1. Can anyone please debug this project for me, or suggest me someway to get it working. This request is urgent. Any helps are much appreciated. PS: If you can't download these file, please let me know, I'll upload to another hosts.

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  • Static content not displayed with Zend FW

    - by shin
    I am trying to display a static content with Zend framework. When I go to http://square.localhost/content/services, I get an error message. Could anyone tell me how to fix this please? Thanks in advance. application.ini .... .... resources.layout.layoutPath = APPLICATION_PATH "/layouts" resources.layout.layout = "master" resources.router.routes.home.route = /home resources.router.routes.home.defaults.module = default resources.router.routes.home.defaults.controller = index resources.router.routes.home.defaults.action = index resources.router.routes.static-content.route = /content/:page resources.router.routes.static-content.defaults.module = default resources.router.routes.static-content.defaults.controller = static-content resources.router.routes.static-content.defaults.action = display application/modules/default/controllers/StaticContentController.php class StaticContentController extends Zend_Controller_Action { public function init() { } // display static views public function displayAction() { $page = $this->getRequest()->getParam('page'); if (file_exists($this->view->getScriptPath(null) . "/" . $this->getRequest()->getControllerName() . "/$page." . $this->viewSuffix)) { $this->render($page); } else { throw new Zend_Controller_Action_Exception('Page not found', 404); } } } application/modules/default/views/scripts/static-content/services.phtml some html ... ... Error message An error occurred Page not found Exception information: Message: Page not found Stack trace: #0 /var/www/square/library/Zend/Controller/Action.php(513): StaticContentController->displayAction() #1 /var/www/square/library/Zend/Controller/Dispatcher/Standard.php(295): Zend_Controller_Action->dispatch('displayAction') #2 /var/www/square/library/Zend/Controller/Front.php(954): Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http)) #3 /var/www/square/library/Zend/Application/Bootstrap/Bootstrap.php(97): Zend_Controller_Front->dispatch() #4 /var/www/square/library/Zend/Application.php(366): Zend_Application_Bootstrap_Bootstrap->run() #5 /var/www/square/public/index.php(26): Zend_Application->run() #6 {main} Request Parameters: array ( 'page' => 'services', 'module' => 'default', 'controller' => 'static-content', 'action' => 'display', )

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  • Case class copy() method abstraction.

    - by Joa Ebert
    I would like to know if it is possible to abstract the copy method of case classes. Basically I have something like sealed trait Op and then something like case class Push(value: Int) extends Op and case class Pop() extends Op. The first problem: A case class without arguments/members does not define a copy method. You can try this in the REPL. scala> case class Foo() defined class Foo scala> Foo().copy() <console>:8: error: value copy is not a member of Foo Foo().copy() ^ scala> case class Foo(x: Int) defined class Foo scala> Foo(0).copy() res1: Foo = Foo(0) Is there a reason why the compiler makes this exception? I think it is rather unituitive and I would expect every case class to define a copy method. The second problem: I have a method def ops: List[Op] and I would like to copy all ops like ops map { _.copy() }. How would I define the copy method in the Op trait? I get a "too many arguments" error if I say def copy(): this.type. However, since all copy() methods have only optional arguments: why is this incorrect? And, how do I do that correct? By making another method named def clone(): this.type and write everywhere def clone() = copy() for all the case classes? I hope not.

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  • JUnit: checking if a void method gets called

    - by nkr1pt
    I have a very simple filewatcher class which checks every 2 seconds if a file has changed and if so, the onChange method (void) is called. Is there an easy way to check ik the onChange method is getting called in a unit test? code: public class PropertyFileWatcher extends TimerTask { private long timeStamp; private File file; public PropertyFileWatcher(File file) { this.file = file; this.timeStamp = file.lastModified(); } public final void run() { long timeStamp = file.lastModified(); if (this.timeStamp != timeStamp) { this.timeStamp = timeStamp; onChange(file); } } protected void onChange(File file) { System.out.println("Property file has changed"); } } @Test public void testPropertyFileWatcher() throws Exception { File file = new File("testfile"); file.createNewFile(); PropertyFileWatcher propertyFileWatcher = new PropertyFileWatcher(file); Timer timer = new Timer(); timer.schedule(propertyFileWatcher, 2000); FileWriter fw = new FileWriter(file); fw.write("blah"); fw.close(); Thread.sleep(8000); // check if propertyFileWatcher.onChange was called file.delete(); }

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  • compiler directive defensive programming for adding ints to nsmuatablearray FMDB/EGODB

    - by johndpope
    I would like to throw a warning message when users try to add an int to an nsmutablearray basically any insert statement that includes values that are not nsstring / nsnumber cause run time crashes. It's exactly the same crash you get when you type %@ instead of %d NSLog(int); The crash is ok, but I want to throw a friendly 'FATAL' message to user. so far I have this try catch with isKindOfClass NSObject but ints are slipping through. #define FATAL_MSG "FATAL: object is not an NSObject subclass. Are you using int? use [NSNumber numberWithInt:1] \n" #define VAToArray(firstarg) ({\ NSMutableArray* valistArray = [NSMutableArray array];\ id obj = nil;\ va_list arguments;\ va_start(arguments, sql);\ @try { \ while ((obj = va_arg(arguments, id))) {\ if([obj isKindOfClass:[NSObject class]]) [valistArray addObject:obj];\ else printf(FATAL_MSG); \ }\ } \ @catch(NSException *exception){ \ printf(FATAL_MSG); \ } \ va_end(arguments);\ valistArray;\ }) - (void)test:(NSString*)sql,... { NSLog(@"VAToArray :%@",VAToArray(sql)); } // then call this [self test:@"str",@"test",nil]; when I call this [self test:@"str",2,nil]; throw the error message.

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  • When software problems reported are not really software problems

    - by AndyUK
    Hi Apologies if this has already been covered or you think it really belongs on wiki. I am a software developer at a company that manufactures microarray printing machines for the biosciences industry. I am primarily involved in interfacing with various bits of hardware (pneumatics, hydraulics, stepper motors, sensors etc) via GUI development in C++ to aspirate and print samples onto microarray slides. On joining the company I noticed that whenever there was a hardware-related problem this would cause the whole setup to freeze, with nobody being any the wiser as to what the specific problem was - hardware / software / misuse etc. Since then I have improved things somewhat by introducing software timeouts and exception handling to better identify and deal with any hardware-related problems that arise eg PLC commands not successfully completed, inappropriate FPGA response commands, and various other deadlock type conditions etc. In addition, the software will now log a summary of the specific problem, inform the user and exit the thread gracefully. This software is not embedded, just interfacing using serial ports. In spite of what has been achieved, non-software guys still do not fully appreciate that in these cases, the 'software' problem they are reporting to me is not really a software problem, rather the software is reporting a problem, but not causing it. Don't get me wrong, there is nothing I enjoy more than to come down on software bugs like a ton of bricks, and looking at ways of improving robustness in any way. I know the system well enough now that I almost have a sixth sense for these things. No matter how many times I try to explain this point to people, it does not really penetrate. They still report what are essentially hardware problems (which eventually get fixed) as software ones. I would like to hear from any others that have endured similar finger-pointing experiences and what methods they used to deal with them.

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  • Django and json request

    - by Hulk
    In a template i have the following code <script> var url="/mypjt/my_timer" $.post(url, paramarr, function callbackHandler(dict) { alert('got response back'); if (dict.flag == 2) { alert('1'); $.jGrowl("Data could not be saved"); } else if(dict.ret_status == 1) { alert('2'); $.jGrowl("Data saved successfully"); window.location = "/mypjt/display/" + dict.rid; } }, "json" ); </script> In views i have the following code, def my_timer(request): dict={} try: a= timer.objects.get(pk=1) dict({'flag':1}) return HttpResponse(simplejson.dumps(dict), mimetype='application/javascript') except: dict({'flag':1}) return HttpResponse(simplejson.dumps(dict), mimetype='application/javascript') My question is since we are making a json request and in the try block ,after setting the flag ,cant we return a page directly as return render_to_response('mypjt/display.html',context_instance=RequestContext(request,{'dict': dict})) instead of sending the response, because on success again in the html page we redirect the code Also if there is a exception then only can we return the json request. My only concern is that the interaction between client and server should be minimal. Thanks..

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  • How to play extracted wave file byte array in C#?

    - by user261924
    At the moment i have managed to separate the left and right channel of a WAVE file and have included the header in a byte[] array. My next step is to be about to play both channels. How can this be done? Here is a code snippet: byte[] song_left = new byte[fa.Length]; byte[] song_right = new byte[fa.Length]; int p = 0; for (int c = 0; c < 43; c++) { song_left[p] = header[c]; p++; } int q = 0; for (s = startByte; s < length; s = s + 3) { song_left[s] = sLeft[q]; q++; s++; song_left[s] = sLeft[q]; q++; } p = 0; for (int c = 0; c < 43; c++) { song_right[p] = header[c]; p++; } This part is reading the header and data from both the right and light channel and saving it to array sLeft[] and sRight[]. This part is working perfectly. Once I obtained the byte arrays, I did the following: System.IO.File.WriteAllBytes("c:\\left.wav", song_left); System.IO.File.WriteAllBytes("c:\\right.wav", song_right); Added a button to play the saved wave file: private void button2_Click(object sender, EventArgs e) { spWave = new SoundPlayer("c:\\left.wav"); spWave.Play(); } Once I hit the play button, this error appers: An unhandled exception of type 'System.InvalidOperationException' occurred in System.dll Additional information: The wave header is corrupt. Any ideas?

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  • Comparison operators not supported for type IList when Paging data in Linq to Sql

    - by Dan
    I can understand what the error is saying - it can't compare a list. Not a problem, other than the fact that I don't know how to not have it compare a list when I want to page through a model with a list as a property. My Model: Event : IEvent int Id string Title // Other stuff.. LazyList<EventDate> Dates // The "problem" property Method which pages the data (truncated): public JsonResult JsonEventList(int skip, int take) { var query = _eventService.GetEvents(); // Do some filtering, then page data.. query = query.Skip(skip).Take(take); return Json(query.ToArray()); } As I said, the above is truncated quite a bit, leaving only the main point of the function: filter, page and return JSON'd data. The exception occurs when I enumerate (.ToArray()). The Event object is really only used to list the common objects of all the event types (Meetings, Birthdays, etc - for example). It still implements IEvent like the other types, so I can't just remove the LazyList<EventDate> Dates' property unless I no longer implementIEvent` Anyway, is there a way to avoid this? I don't really want to compare a LazyList when I page, but I do not know how to resolve this issue. Thank you in advance! :)

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  • Shall this Regex do what I expect from it, that is, matching against "A1:B10,C3,D4:E1000"?

    - by Will Marcouiller
    I'm currently writing a library where I wish to allow the user to be able to specify spreadsheet cell(s) under four possible alternatives: A single cell: "A1"; Multiple contiguous cells: "A1:B10" Multiple separate cells: "A1,B6,I60,AA2" A mix of 2 and 3: "B2:B12,C13:C18,D4,E11000" Then, to validate whether the input respects these formats, I intended to use a regular expression to match against. I have consulted this article on Wikipedia: Regular Expression (Wikipedia) And I also found this related SO question: regex matching alpha character followed by 4 alphanumerics. Based on the information provided within the above-linked articles, I would try with this Regex: Default Readonly Property Cells(ByVal cellsAddresses As String) As ReadOnlyDictionary(Of String, ICell) Get Dim validAddresses As Regex = New Regex("A-Za-z0-9:,A-Za-z0-9") If (Not validAddresses.IsMatch(cellsAddresses)) then _ Throw New FormatException("cellsAddresses") // Proceed with getting the cells from the Interop here... End Get End Property Questions 1. Is my regular expression correct? If not, please help me understand what expression I could use. 2. What exception is more likely to be the more meaningful between a FormatException and an InvalidExpressionException? I hesitate here, since it is related to the format under which the property expect the cells to be input, aside, I'm using an (regular) expression to match against. Thank you kindly for your help and support! =)

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  • MVC2 DataAnnotations on ViewModel - Don't understand using it with MVVM pattern

    - by ScottSEA
    I have an MVC2 Application that uses MVVM pattern. I am trying use Data Annotations to validate form input. In my ThingsController I have two methods: [HttpGet] public ActionResult Index() { return View(); } public ActionResult Details(ThingsViewModel tvm) { if (!ModelState.IsValid) return View(tvm); try { Query q = new Query(tvm.Query); ThingRepository repository = new ThingRepository(q); tvm.Things = repository.All(); return View(tvm); } catch (Exception) { return View(); } } My Details.aspx view is strongly typed to the ThingsViewModel: <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<Config.Web.Models.ThingsViewModel>" %> The ViewModel is a class consisting of a IList of returned Thing objects and the Query string (which is submitted on the form) and has the Required data annotation: public class ThingsViewModel { public IList<Thing> Things{ get; set; } [Required(ErrorMessage="You must enter a query")] public string Query { get; set; } } When I run this, and click the submit button on the form without entering a value I get a YSOD with the following error: The model item passed into the dictionary is of type 'Config.Web.Models.ThingsViewModel', but this dictionary requires a model item of type System.Collections.Generic.IEnumerable`1[Config.Domain.Entities.Thing]'. How can I get Data Annotations to work with a ViewModel? I cannot see what I'm missing or where I'm going wrong - the VM was working just fine before I started mucking around with validation.

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