Search Results

Search found 38690 results on 1548 pages for 'try catch throw'.

Page 42/1548 | < Previous Page | 38 39 40 41 42 43 44 45 46 47 48 49  | Next Page >

  • Sending an email when an Exception is Thrown

    - by hariubc
    Hi: I have written a java class where if a method throws an exception, an email is sent, via java mail, with a report to the administrators. It works - my question is w.r.t elegance - to catch the exception thrown by the main method, the sendEmail() method resides in the catch block of the main method. The sendEmail() method has its own try-catch block. In effect - it looks like below - is there a more beautiful way of writing this? try { foo; } catch { try{ sendEmail(); } catch { log(e.message); } }

    Read the article

  • Exception Handling in MVP Passive View

    - by ilmatte
    Hello, I'm wondering what's the preferred way to manage exceptions in an MVP implemented with a Passive View. There's a discussion in my company about putting try/catch blocks in the presenter or only in the view. In my opinion the logical top level caller is the presenter (even if the actual one is the view). Moreover I can test the presenter and not the view. This is the reason why I prefer to define a method in the view interface: IView.ShowError(error) and invoke it from the catch blocks in the presenter: try { } catch (Exception exception) { ...log exception... view.ShowError("An error occurred") } In this way the developers of future views can safely forget to implement exception handling but the IView interface force them to implement a ShowError method. The drawback is that if I want to feel completely safe I need to add redundant try/catch blocks in the view. The other way would be to add try catch blocks only in the views and not introducing the showerror method in the view interface. What do you suggest?

    Read the article

  • I have a ConnectException that isn't being caught for some reason

    - by aakbari1024
    I'm working on an Android application that uses sockets. I have a function called initializeStreams() which opens the socket and attempts a connection. This function throws a ConnectException if the connection could not be established. But for some reason, in the code that calls initializeStreams(), which has a catch block for ConnectException, the log prints out its own stack trace for the exception instead of going to the catch block. The catch block is never reached at all, even though the exact exception is being thrown. Here's the code: The try block: try { initializeStreams(); /* drivesList = new ArrayList<String>(); drivesList = enumerateDrives();*/ } catch (ConnectException e) { //Log.i(TAG, "caught connect exception"); /*loadingProgress.dismiss(); retryConnection();*/ } initializeStreams(): public void initializeStreams() throws ConnectException { try { Log.i(TAG, "Attempting to connect"); requestSocket = new Socket(SERVER_ADDR, PORT); /* other code */ } catch (IOException e) { e.printStackTrace(); } I can't figure this out, so any help would be much appreciated. }

    Read the article

  • How to refactor use of the general Exception?

    - by Colin
    Our code catches the general exception everywhere. Usually it writes the error to a log table in the database and shows a MessageBox to the user to say that the operation requested failed. If there is database interaction, the transaction is rolled back. I have introduced a business logic layer and a data access layer to unravel some of the logic. In the data access layer, I have chosen not to catch anything and I also throw ArgumentNullExceptions and ArgumentOutOfRangeExceptions so that the message passed up the stack does not come straight from the database. In the business logic layer I put a try catch. In the catch I rollback the transaction, do the logging and rethrow. In the presentation layer there is another try catch that displays a MessageBox. I am now thinking about catching a DataException and an ArgumentException instead of an Exception where I know the code only accesses a database. Where the code accesses a web service, then I thought I would create my own "WebServiceException", which would be created in the data access layer whenever an HttpException, WebException or SoapException is thrown. So now, generally I will be catching 2 or 3 exceptions where currently I catch just the general Exception, and I think that seems OK to me. Does anyone wrap exceptions up again to carry the message up to the presentation layer? I think I should probably add a try catch to Main() that catches Exception, attempts to log it, displays an "Application has encountered an error" message and exits the application. So, my question is, does anyone see any holes in my plan? Are there any obvious exceptions that I should be catching or do these ones pretty much cover it (other than file access - I think there is only 1 place where we read-write to a config file).

    Read the article

  • JMS MessageCreator.createMessage() in Grails

    - by Hans Wurst
    Hi there, I am trying to implement jms to my grails application. I have several JMS consumer in a spring based enviroment listining on an ActiveMQ broker. I wrote a simple test commandline client which creates messages and receives them in an request response manner. Here is the snippet that sends a MapMessage in Spring JMS way. This works for me as long I am in my spring world. final String corrID = UUID.randomUUID().toString(); asyncJmsTemplate.send("test.RequestQ", new MessageCreator() { public Message createMessage(Session session) throws JMSException { try { MapMessage msg = session.createMapMessage(); msg.setStringProperty("json", mapper.writeValueAsString(List<of some objects>)); msg.setJMSCorrelationID(corrID); msg.setJMSReplyTo(session.createQueue("test.ReplyQ")); return msg; } catch (JsonGenerationException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (JsonMappingException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } }); BUT when I tried to implement this methods to my grails test app I receive some METHOD_DEF exceptions. Sending simple TextMessages via the jmsTemplate.convertAndSende(Queue, Message) provided by the JMS Plugin works. Can any one help me? Is this a common problem? Cheers Hans

    Read the article

  • how to continuously send data without blocking?

    - by Donal Rafferty
    I am trying to send rtp audio data from my Android application. I currently can send 1 RTP packet with the code below and I also have another class that extends Thread that listens to and receives RTP packets. My question is how do I continuously send my updated buffer through the packet payload without blocking the receiving thread? public void run() { isRecording = true; android.os.Process.setThreadPriority (android.os.Process.THREAD_PRIORITY_URGENT_AUDIO); int buffersize = AudioRecord.getMinBufferSize(8000, AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT); Log.d("BUFFERSIZE","Buffer size = " + buffersize); arec = new AudioRecord(MediaRecorder.AudioSource.MIC, 8000, AudioFormat.CHANNEL_CONFIGURATION_MONO, AudioFormat.ENCODING_PCM_16BIT, buffersize); short[] readBuffer = new short[80]; byte[] buffer = new byte[160]; arec.startRecording(); while(arec.getRecordingState() == AudioRecord.RECORDSTATE_RECORDING){ int frames = arec.read(readBuffer, 0, 80); @SuppressWarnings("unused") int lenghtInBytes = codec.encode(readBuffer, 0, buffer, frames); RtpPacket rtpPacket = new RtpPacket(); rtpPacket.setV(2); rtpPacket.setX(0); rtpPacket.setM(0); rtpPacket.setPT(0); rtpPacket.setSSRC(123342345); rtpPacket.setPayload(buffer, 160); try { rtpSession2.sendRtpPacket(rtpPacket); } catch (UnknownHostException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (RtpException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } So when I send on one device and receive on another I get decent audio, but when I send and receive on both I get broken sound like its taking turns to send and receive audio. I have a feeling it could be to do with the while loop? it could be looping around in there and not letting anything else run?

    Read the article

  • ListView Parsing Persian xml

    - by Namikaze Minato
    I used a tutorial about listview parsing xm from internet and using LasyAdapter shows the items in listview. When I add persian characters in xml (into one of childnodes) the result is some boxes in listview (after showing the text in listview). The format of xml is UTF-8, too. I used typeface too (but didn't work). Besides when I type Pwesian into the application it shows alright but it can't show Persiann content parsed from xml. Thanks in advance. I updated the post with original XMLparser (which was the problem). public String getXmlFromUrl(String url) { String xml = null; try { // defaultHttpClient DefaultHttpClient httpClient = new DefaultHttpClient(); HttpPost httpPost = new HttpPost(url); HttpResponse httpResponse = httpClient.execute(httpPost); HttpEntity httpEntity = httpResponse.getEntity(); xml = EntityUtils.toString(httpEntity); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } // return XML return xml; } public Document getDomElement(String xml) { Document doc = null; DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); try { DocumentBuilder db = dbf.newDocumentBuilder(); InputSource is = new InputSource(); is.setCharacterStream(new StringReader(xml)); doc = db.parse(is); } catch (ParserConfigurationException e) { Log.e("Error: ", e.getMessage()); return null; } catch (SAXException e) { Log.e("Error: ", e.getMessage()); return null; } catch (IOException e) { Log.e("Error: ", e.getMessage()); return null; } return doc; }

    Read the article

  • Beginner: Restore previously serialized JFrame-object, how?

    - by elementz
    Hi all. I have managed to serialize my very basic GUI-object containing a JTextArea and a few buttons to a file 'test.ser'. Now, I would like to completely restore the previously saved state from 'test.ser', but seem to have a misconception of how to properly deserialize an objects state. The class MyFrame creates the JFrame and serializes it. Now I tried to deserialize like so: public class Deserialize { static Deserialize ds; MyFrame frame; public static void main(String[] args) { try { ds.deserialize(); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void deserialize() throws ClassNotFoundException { try { ObjectInputStream ois = new ObjectInputStream(new FileInputStream("test.ser")); frame = (MyFrame) ois.readObject(); ois.close(); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } Maybe somebody could point me into the direction where my misconception is? Thx in advance!

    Read the article

  • Read quicktime movie from servlet in a webpage?

    - by khue
    Hi, I have a servlet that construct response to a media file request by reading the file from server: File uploadFile = new File("C:\\TEMP\\movie.mov"); FileInputStream in = new FileInputStream(uploadFile); Then write that stream to the response stream. My question is how do I play the media file in the webpage using embed or object tag to read the media stream from the response? Here is my code in the servlet: public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.getParameter("location"); uploadFile(response); } private void uploadFile(HttpServletResponse response) { File transferFile = new File("C:/TEMP/captured.mov"); FileInputStream in = null; try { in = new FileInputStream(transferFile); } catch (FileNotFoundException e) { System.out.println("File not found"); } try { System.out.println("in byes i s" + in.available()); } catch (IOException e) { } DataOutputStream responseStream = null; try { responseStream = new DataOutputStream(response.getOutputStream()); } catch (IOException e) { System.out.println("Io exception"); } try { Util.copyStream(in, responseStream); } catch (CopyStreamException e) { System.out.println("copy Stream exception"); } try { responseStream.flush(); } catch (IOException e) { } try { responseStream.close(); } catch (IOException e) { } } And here is html page as Ryan suggested: <embed SRC="http://localhost:7101/movies/transferservlet" WIDTH=100 HEIGHT=196 AUTOPLAY=true CONTROLLER=true LOOP=false PLUGINSPAGE="http://www.apple.com/quicktime/"> Any ideas?

    Read the article

  • when I am executing webdriver scripts from command prompt I get error "could not find or load main class

    - by Rahul Belhekar
    I want to run below java file from command prompt. whenever I am running it from command line it gives error "Error:Could not find or load main class".This is regular java code.It runs well in eclipse but gives this error in command prompt.I have set classpath till my project bin also set "path" till bin folder of jdk, this file is getting compiled but not running from command prompt.please help me to resolve my issue.Waiting for your reply thank you public class RILookBookGetTheLook extends Libraryfile { public static void main(String[] args) { //Delcaring objects //String className = this.getClass().getName(); WebDriver driver; String baseUrl; final Log LOG = LogFactory.getLog(BrowserLocator.class); CsvWriter out; try { setUp(); } catch (Exception e1) { // TODO Auto-generated catch block e1.printStackTrace(); } try { Display_ProductPage(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } try { tearDown(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } I have written methods here which I called from main method Please guys help me to solve this problem

    Read the article

  • How to differentiate between exceptions i can show the user, and ones i can't?

    - by Ian Boyd
    i have some business logic that traps some logically invalid situations, e.g. trying to reverse a transaction that was already reversed. In this case the correct action is to inform the user: Transaction already reversed or Cannot reverse a reversing transaction or You do not have permission to reverse transactions or This transaction is on a session that has already been closed or This transaction is too old to be reversed The question is, how do i communicate these exceptional cases back to the calling code, so they can show the user? Do i create a separate exception for each case: catch (ETransactionAlreadyReversedException) MessageBox.Show('Transaction already reversed') catch (EReversingAReversingTransactionException) MessageBox.Show('Cannot reverse a reversing transaction') catch (ENoPermissionToReverseTranasctionException) MessageBox.Show('You do not have permission to reverse transactions') catch (ECannotReverseTransactionOnAlredyClosedSessionException) MessageBox.Show('This transaction is on a session that has already been closed') catch (ECannotReverseTooOldTransactionException) MessageBox.Show('This transaction is too old to be reversed') Downside for this is that when there's a new logical case to show the user: Tranasctions created by NSL cannot be reversed i don't simply show the user a message, and instead it leaks out as an unhandled excpetion, when really it should be handled with another MessageBox. The alternative is to create a single exception class: `EReverseTransactionException` With the understanding that any exception of this type is a logical check, that should be handled with a message box: catch (EReverseTransactionException) But it's still understood that any other exceptions, ones that involve, for example, an memory ECC parity error, continue unhandled. In other words, i don't convert all errors that can be thrown by the ReverseTransaction() method into EReverseTransactionException, only ones that are logically invalid cause of the user.

    Read the article

  • ASP.NET Web API Exception Handling

    - by Fredrik N
    When I talk about exceptions in my product team I often talk about two kind of exceptions, business and critical exceptions. Business exceptions are exceptions thrown based on “business rules”, for example if you aren’t allowed to do a purchase. Business exceptions in most case aren’t important to log into a log file, they can directly be shown to the user. An example of a business exception could be "DeniedToPurchaseException”, or some validation exceptions such as “FirstNameIsMissingException” etc. Critical Exceptions are all other kind of exceptions such as the SQL server is down etc. Those kind of exception message need to be logged and should not reach the user, because they can contain information that can be harmful if it reach out to wrong kind of users. I often distinguish business exceptions from critical exceptions by creating a base class called BusinessException, then in my error handling code I catch on the type BusinessException and all other exceptions will be handled as critical exceptions. This blog post will be about different ways to handle exceptions and how Business and Critical Exceptions could be handled. Web API and Exceptions the basics When an exception is thrown in a ApiController a response message will be returned with a status code set to 500 and a response formatted by the formatters based on the “Accept” or “Content-Type” HTTP header, for example JSON or XML. Here is an example:   public IEnumerable<string> Get() { throw new ApplicationException("Error!!!!!"); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The response message will be: HTTP/1.1 500 Internal Server Error Content-Length: 860 Content-Type: application/json; charset=utf-8 { "ExceptionType":"System.ApplicationException","Message":"Error!!!!!","StackTrace":" at ..."} .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The stack trace will be returned to the client, this is because of making it easier to debug. Be careful so you don’t leak out some sensitive information to the client. So as long as you are developing your API, this is not harmful. In a production environment it can be better to log exceptions and return a user friendly exception instead of the original exception. There is a specific exception shipped with ASP.NET Web API that will not use the formatters based on the “Accept” or “Content-Type” HTTP header, it is the exception is the HttpResponseException class. Here is an example where the HttpReponseExcetpion is used: // GET api/values [ExceptionHandling] public IEnumerable<string> Get() { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError)); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The response will not contain any content, only header information and the status code based on the HttpStatusCode passed as an argument to the HttpResponseMessage. Because the HttpResponsException takes a HttpResponseMessage as an argument, we can give the response a content: public IEnumerable<string> Get() { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent("My Error Message"), ReasonPhrase = "Critical Exception" }); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The code above will have the following response:   HTTP/1.1 500 Critical Exception Content-Length: 5 Content-Type: text/plain; charset=utf-8 My Error Message .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The Content property of the HttpResponseMessage doesn’t need to be just plain text, it can also be other formats, for example JSON, XML etc. By using the HttpResponseException we can for example catch an exception and throw a user friendly exception instead: public IEnumerable<string> Get() { try { DoSomething(); return new string[] { "value1", "value2" }; } catch (Exception e) { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent("An error occurred, please try again or contact the administrator."), ReasonPhrase = "Critical Exception" }); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Adding a try catch to every ApiController methods will only end in duplication of code, by using a custom ExceptionFilterAttribute or our own custom ApiController base class we can reduce code duplicationof code and also have a more general exception handler for our ApiControllers . By creating a custom ApiController’s and override the ExecuteAsync method, we can add a try catch around the base.ExecuteAsync method, but I prefer to skip the creation of a own custom ApiController, better to use a solution that require few files to be modified. The ExceptionFilterAttribute has a OnException method that we can override and add our exception handling. Here is an example: using System; using System.Diagnostics; using System.Net; using System.Net.Http; using System.Web.Http; using System.Web.Http.Filters; public class ExceptionHandlingAttribute : ExceptionFilterAttribute { public override void OnException(HttpActionExecutedContext context) { if (context.Exception is BusinessException) { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent(context.Exception.Message), ReasonPhrase = "Exception" }); } //Log Critical errors Debug.WriteLine(context.Exception); throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent("An error occurred, please try again or contact the administrator."), ReasonPhrase = "Critical Exception" }); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Note: Something to have in mind is that the ExceptionFilterAttribute will be ignored if the ApiController action method throws a HttpResponseException. The code above will always make sure a HttpResponseExceptions will be returned, it will also make sure the critical exceptions will show a more user friendly message. The OnException method can also be used to log exceptions. By using a ExceptionFilterAttribute the Get() method in the previous example can now look like this: public IEnumerable<string> Get() { DoSomething(); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } To use the an ExceptionFilterAttribute, we can for example add the ExceptionFilterAttribute to our ApiControllers methods or to the ApiController class definition, or register it globally for all ApiControllers. You can read more about is here. Note: If something goes wrong in the ExceptionFilterAttribute and an exception is thrown that is not of type HttpResponseException, a formatted exception will be thrown with stack trace etc to the client. How about using a custom IHttpActionInvoker? We can create our own IHTTPActionInvoker and add Exception handling to the invoker. The IHttpActionInvoker will be used to invoke the ApiController’s ExecuteAsync method. Here is an example where the default IHttpActionInvoker, ApiControllerActionInvoker, is used to add exception handling: public class MyApiControllerActionInvoker : ApiControllerActionInvoker { public override Task<HttpResponseMessage> InvokeActionAsync(HttpActionContext actionContext, System.Threading.CancellationToken cancellationToken) { var result = base.InvokeActionAsync(actionContext, cancellationToken); if (result.Exception != null && result.Exception.GetBaseException() != null) { var baseException = result.Exception.GetBaseException(); if (baseException is BusinessException) { return Task.Run<HttpResponseMessage>(() => new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent(baseException.Message), ReasonPhrase = "Error" }); } else { //Log critical error Debug.WriteLine(baseException); return Task.Run<HttpResponseMessage>(() => new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent(baseException.Message), ReasonPhrase = "Critical Error" }); } } return result; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } You can register the IHttpActionInvoker with your own IoC to resolve the MyApiContollerActionInvoker, or add it in the Global.asax: GlobalConfiguration.Configuration.Services.Remove(typeof(IHttpActionInvoker), GlobalConfiguration.Configuration.Services.GetActionInvoker()); GlobalConfiguration.Configuration.Services.Add(typeof(IHttpActionInvoker), new MyApiControllerActionInvoker()); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   How about using a Message Handler for Exception Handling? By creating a custom Message Handler, we can handle error after the ApiController and the ExceptionFilterAttribute is invoked and in that way create a global exception handler, BUT, the only thing we can take a look at is the HttpResponseMessage, we can’t add a try catch around the Message Handler’s SendAsync method. The last Message Handler that will be used in the Wep API pipe-line is the HttpControllerDispatcher and this Message Handler is added to the HttpServer in an early stage. The HttpControllerDispatcher will use the IHttpActionInvoker to invoke the ApiController method. The HttpControllerDipatcher has a try catch that will turn ALL exceptions into a HttpResponseMessage, so that is the reason why a try catch around the SendAsync in a custom Message Handler want help us. If we create our own Host for the Wep API we could create our own custom HttpControllerDispatcher and add or exception handler to that class, but that would be little tricky but is possible. We can in a Message Handler take a look at the HttpResponseMessage’s IsSuccessStatusCode property to see if the request has failed and if we throw the HttpResponseException in our ApiControllers, we could use the HttpResponseException and give it a Reason Phrase and use that to identify business exceptions or critical exceptions. I wouldn’t add an exception handler into a Message Handler, instead I should use the ExceptionFilterAttribute and register it globally for all ApiControllers. BUT, now to another interesting issue. What will happen if we have a Message Handler that throws an exception?  Those exceptions will not be catch and handled by the ExceptionFilterAttribute. I found a  bug in my previews blog post about “Log message Request and Response in ASP.NET WebAPI” in the MessageHandler I use to log incoming and outgoing messages. Here is the code from my blog before I fixed the bug:   public abstract class MessageHandler : DelegatingHandler { protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) { var corrId = string.Format("{0}{1}", DateTime.Now.Ticks, Thread.CurrentThread.ManagedThreadId); var requestInfo = string.Format("{0} {1}", request.Method, request.RequestUri); var requestMessage = await request.Content.ReadAsByteArrayAsync(); await IncommingMessageAsync(corrId, requestInfo, requestMessage); var response = await base.SendAsync(request, cancellationToken); var responseMessage = await response.Content.ReadAsByteArrayAsync(); await OutgoingMessageAsync(corrId, requestInfo, responseMessage); return response; } protected abstract Task IncommingMessageAsync(string correlationId, string requestInfo, byte[] message); protected abstract Task OutgoingMessageAsync(string correlationId, string requestInfo, byte[] message); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   If a ApiController throws a HttpResponseException, the Content property of the HttpResponseMessage from the SendAsync will be NULL. So a null reference exception is thrown within the MessageHandler. The yellow screen of death will be returned to the client, and the content is HTML and the Http status code is 500. The bug in the MessageHandler was solved by adding a check against the HttpResponseMessage’s IsSuccessStatusCode property: public abstract class MessageHandler : DelegatingHandler { protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) { var corrId = string.Format("{0}{1}", DateTime.Now.Ticks, Thread.CurrentThread.ManagedThreadId); var requestInfo = string.Format("{0} {1}", request.Method, request.RequestUri); var requestMessage = await request.Content.ReadAsByteArrayAsync(); await IncommingMessageAsync(corrId, requestInfo, requestMessage); var response = await base.SendAsync(request, cancellationToken); byte[] responseMessage; if (response.IsSuccessStatusCode) responseMessage = await response.Content.ReadAsByteArrayAsync(); else responseMessage = Encoding.UTF8.GetBytes(response.ReasonPhrase); await OutgoingMessageAsync(corrId, requestInfo, responseMessage); return response; } protected abstract Task IncommingMessageAsync(string correlationId, string requestInfo, byte[] message); protected abstract Task OutgoingMessageAsync(string correlationId, string requestInfo, byte[] message); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } If we don’t handle the exceptions that can occur in a custom Message Handler, we can have a hard time to find the problem causing the exception. The savior in this case is the Global.asax’s Application_Error: protected void Application_Error() { var exception = Server.GetLastError(); Debug.WriteLine(exception); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } I would recommend you to add the Application_Error to the Global.asax and log all exceptions to make sure all kind of exception is handled. Summary There are different ways we could add Exception Handling to the Wep API, we can use a custom ApiController, ExceptionFilterAttribute, IHttpActionInvoker or Message Handler. The ExceptionFilterAttribute would be a good place to add a global exception handling, require very few modification, just register it globally for all ApiControllers, even the IHttpActionInvoker can be used to minimize the modifications of files. Adding the Application_Error to the global.asax is a good way to catch all unhandled exception that can occur, for example exception thrown in a Message Handler.   If you want to know when I have posted a blog post, you can follow me on twitter @fredrikn

    Read the article

  • MVC2 Client validation with Annotations in View with RenderAction

    - by Olle
    I'm having problem with client side validation on a View that renders a dropdownlist with help of a Html.RenderAction. I have two controllers. SpecieController and CatchController and I've created ViewModels for my views. I want to keep it as DRY as possible and I will most probably need a DropDownList for all Specie elsewhere in the near future. When I create a Catch i need to set a relationship to one specie, I do this with an id that I get from the DropDownList of Species. ViewModels.Catch.Create [Required] public int Length { get; set; } [Required] public int Weight { get; set; } [Required] [Range(1, int.MaxValue)] public int SpecieId { get; set; } ViewModels.Specie.List public DropDownList(IEnumerable<SelectListItem> species) { this.Species = species; } public IEnumerable<SelectListItem> Species { get; private set; } My View for the Catch.Create action uses the ViewModels.Catch.Create as a model. But it feels that I'm missing something in the implemetation. What I want in my head is to connect the selected value in the DropDownList that comes from the RenderAction to my SpecieId. View.Catch.Create <div class="editor-label"> <%: Html.LabelFor(model => model.SpecieId) %> </div> <div class="editor-field"> <%-- Before DRY refactoring, works like I want but not DRY <%: Html.DropDownListFor(model => model.SpecieId, Model.Species) %> --%> <% Html.RenderAction("DropDownList", "Specie"); %> <%: Html.ValidationMessageFor(model => model.SpecieId) %> </div> CatchController.Create [HttpPost] public ActionResult Create(ViewModels.CatchModels.Create myCatch) { if (ModelState.IsValid) { // Can we make this StronglyTyped? int specieId = int.Parse(Request["Species"]); // Save to db Catch newCatch = new Catch(); newCatch.Length = myCatch.Length; newCatch.Weight = myCatch.Weight; newCatch.Specie = SpecieService.GetById(specieId); newCatch.User = UserService.GetUserByUsername(User.Identity.Name); CatchService.Save(newCatch); } This scenario works but not as smooth as i want. ClientSide validation does not work for SpecieId (after i refactored), I see why but don't know how I can ix it. Can I "glue" the DropDownList SelectedValue into myCatch so I don't need to get the value from Request["Species"] Thanks in advance for taking your time on this.

    Read the article

  • MSDN Example of handling an exception from the TPL - Is this a race condition?

    - by David
    I'm looking at the TPL exception handling example from MSDN @ http://msdn.microsoft.com/en-us/library/dd537614(v=VS.100).aspx The basic form of the code is: Task task1 = Task.Factory.StartNew(() => { throw new IndexOutOfRangeException(); }); try { task1.Wait(); } catch (AggregateException ae) { throw ae.Flatten(); } My question is: Is this a race condition? What happens if task1 throws before the try has executed? Am I missing something that stops this being a race? Shouldn't it be written like this instead: try { Task task1 = Task.Factory.StartNew(() => { throw new IndexOutOfRangeException(); }); task1.Wait(); } catch (AggregateException ae) { throw ae.Flatten(); }

    Read the article

  • Help with SDL_mixer (no sound)

    - by Kaizoku
    Hello, I have this strange problem with SDL_mixer, it doesn't want to play music. It doesn't throw any error, it just skips it. Any advice? I am compiling on linux with libvorbis. audio.h #ifndef AUDIO_H #define AUDIO_H #include <string> #include <SDL/SDL_mixer.h> class Audio { private: Mix_Music *music; public: Audio(); virtual ~Audio(); public: void setMusic(std::string path); void playMusic(); }; #endif /* AUDIO_H */ audio.cpp #include "Audio.h" #include <stdexcept> Audio::Audio() { if (0 == Mix_Init(MIX_INIT_OGG)) throw std::runtime_error(Mix_GetError()); if (-1 == Mix_OpenAudio(44100, MIX_DEFAULT_FORMAT, MIX_DEFAULT_CHANNELS, 4096)) throw std::runtime_error(Mix_GetError()); } Audio::~Audio() { Mix_FreeMusic(music); Mix_Quit(); } void Audio::setMusic(std::string path) { music = Mix_LoadMUS(path.c_str()); if (NULL == music) throw std::runtime_error(Mix_GetError()); } void Audio::playMusic() { if (NULL != music) { if (-1 == Mix_PlayMusic(music, -1)) throw std::runtime_error(Mix_GetError()); } }

    Read the article

  • Catching an exception class within a template

    - by Todd Bauer
    I'm having a problem using the exception class Overflow() for a Stack template I'm creating. If I define the class regularly there is no problem. If I define the class as a template, I cannot make my call to catch() work properly. I have a feeling it's simply syntax, but I can't figure it out for the life of me. #include<iostream> #include<exception> using namespace std; template <class T> class Stack { private: T *stackArray; int size; int top; public: Stack(int size) { this->size = size; stackArray = new T[size]; top = 0; } ~Stack() { delete[] stackArray; } void push(T value) { if (isFull()) throw Overflow(); stackArray[top] = value; top++; } bool isFull() { if (top == size) return true; else return false; } class Overflow {}; }; int main() { try { Stack<double> Stack(5); Stack.push( 5.0); Stack.push(10.1); Stack.push(15.2); Stack.push(20.3); Stack.push(25.4); Stack.push(30.5); } catch (Stack::Overflow) { cout << "ERROR! The stack is full.\n"; } return 0; } The problem is in the catch (Stack::Overflow) statement. As I said, if the class is not a template, this works just fine. However, once I define it as a template, this ceases to work. I've tried all sorts of syntaxes, but I always get one of two sets of error messages from the compiler. If I use catch(Stack::Overflow): ch18pr01.cpp(89) : error C2955: 'Stack' : use of class template requires template argument list ch18pr01.cpp(13) : see declaration of 'Stack' ch18pr01.cpp(89) : error C2955: 'Stack' : use of class template requires template argument list ch18pr01.cpp(13) : see declaration of 'Stack' ch18pr01.cpp(89) : error C2316: 'Stack::Overflow' : cannot be caught as the destructor and/or copy constructor are inaccessible EDIT: I meant If I use catch(Stack<double>::Overflow) or any variety thereof: ch18pr01.cpp(89) : error C2061: syntax error : identifier 'Stack' ch18pr01.cpp(89) : error C2310: catch handlers must specify one type ch18pr01.cpp(95) : error C2317: 'try' block starting on line '75' has no catch handlers I simply can not figure this out. Does anyone have any idea?

    Read the article

  • Help with Linq Expression - INotifyPropertyChanged

    - by Stephen Patten
    Hello, I'm reading the source code from the latest Prism 4 drop and am interested in solving this problem. There is a base class for the ViewModels that implements INotifyPropertyChanged and INotifyDataErrorInfo and provides some refactoring friendly change notification. protected void RaisePropertyChanged<T>(Expression<Func<T>> propertyExpresssion) { var propertyName = ExtractPropertyName(propertyExpresssion); this.RaisePropertyChanged(propertyName); } private string ExtractPropertyName<T>(Expression<Func<T>> propertyExpresssion) { if (propertyExpresssion == null) { throw new ArgumentNullException("propertyExpression"); } var memberExpression = propertyExpresssion.Body as MemberExpression; if (memberExpression == null) { throw new ArgumentException("The expression is not a member access expression.", "propertyExpression"); } var property = memberExpression.Member as PropertyInfo; if (property == null) { throw new ArgumentException("The member access expression does not access property.","propertyExpression"); } if (!property.DeclaringType.IsAssignableFrom(this.GetType())) { throw new ArgumentException("The referenced property belongs to a different type.", "propertyExpression"); } var getMethod = property.GetGetMethod(true); if (getMethod == null) { // this shouldn't happen - the expression would reject the property before reaching this far throw new ArgumentException("The referenced property does not have a get method.", "propertyExpression"); } if (getMethod.IsStatic) { throw new ArgumentException("The referenced property is a static property.", "propertyExpression"); } return memberExpression.Member.Name; } and as an example of it's usage private void RetrieveNewQuestionnaire() { this.Questions.Clear(); var template = this.questionnaireService.GetQuestionnaireTemplate(); this.questionnaire = new Questionnaire(template); foreach (var question in this.questionnaire.Questions) { this.Questions.Add(this.CreateQuestionViewModel(question)); } this.RaisePropertyChanged(() => this.Name); this.RaisePropertyChanged(() => this.UnansweredQuestions); this.RaisePropertyChanged(() => this.TotalQuestions); this.RaisePropertyChanged(() => this.CanSubmit); } My question is this. What would it take to pass an array of the property names to an overloaded method (RaisePropertyChanged) and condense this last bit of code from 4 lines to 1? Thank you, Stephen

    Read the article

  • problem with dmg file

    - by madalina
    Hello, I have created a dmg file named try.dmg which contains an executable application myapplication.app together with a compiled library mylibrary.lib; I used Disk Utility in order to create the try.dmg file. I mounted the try.dmg file on my computer and I opened the application myapplication.app with no problems. Still, I tried to do the same thing on another Macintosh, with the same operating system Mac OS X, but I got some problems: I mounted the try.dmg file and then when I tried to open the application myapplication.app I got an error message, that the application has quit unexpectedly. Can someone explain me what is it happening? How come this try.dmg file can be mounted and the application can be opened with no problems on my computer with Mac OS X, but on another computer with Mac OS X, after I mount the try.dmg file I get errors when I try opening the application? Thank you very much for your help. Best wishes, Madalina

    Read the article

  • How can i return abstract class from any factory?

    - by programmerist
    using System; using System.Collections.Generic; using System.Linq; using System.Web; namespace EfTestFactory { public abstract class _Company { public abstract List<Personel> GetPersonel(); public abstract List<Prim> GetPrim(); public abstract List<Finans> GetFinans(); } public abstract class _Radyoloji { public abstract List<string> GetRadyoloji(); } public abstract class _Satis { public abstract List<string> GetSatis(); } public abstract class _Muayene { public abstract List<string> GetMuayene(); } public class Company : _Company { public override List<Personel> GetPersonel() { throw new NotImplementedException(); } public override List<Prim> GetPrim() { throw new NotImplementedException(); } public override List<Finans> GetFinans() { throw new NotImplementedException(); } } public class Radyoloji : _Radyoloji { public override List<string> GetRadyoloji() { throw new NotImplementedException(); } } public class Satis : _Satis { public override List<string> GetSatis() { throw new NotImplementedException(); } } public class Muayene : _Muayene { public override List<string> GetMuayene() { throw new NotImplementedException(); } } public class GenoTipController { public object CreateByEnum(DataModelType modeltype) { string enumText = modeltype.ToString(); // will return for example "Company" Type classType = Type.GetType(enumText); // the Type for Company class object t = Activator.CreateInstance(classType); // create an instance of Company class return t; } } public class AntsController { static Dictionary<DataModelType, Func<object>> s_creators = new Dictionary<DataModelType, Func<object>>() { { DataModelType.Radyoloji, () => new _Radyoloji() }, { DataModelType.Company, () => new _Company() }, { DataModelType.Muayene, () => new _Muayene() }, { DataModelType.Satis, () => new _Satis() }, }; public object CreateByEnum(DataModelType modeltype) { return s_creators[modeltype](); } } public class CompanyView { public static List<Personel> GetPersonel() { GenoTipController controller = new GenoTipController(); _Company company = controller.CreateByEnum(DataModelType.Company) as _Company; return company.GetPersonel(); } } public enum DataModelType { Radyoloji, Satis, Muayene, Company } } if i write above codes i see some error: Cannot create an instance of abstract class or interface 'EfTestFactory_Company'How can i solve it? Look please below pic.

    Read the article

  • Image rescale and write rescaled image file in blackberry

    - by Karthick
    I am using the following code to resize and save the file in to the blackberry device. After image scale I try to write image file into device. But it gives the same data. (Height and width of the image are same).I have to make rescaled image file.Can anyone help me ??? class ResizeImage extends MainScreen implements FieldChangeListener { private String path="file:///SDCard/BlackBerry/pictures/test.jpg"; private ButtonField btn; ResizeImage() { btn=new ButtonField("Write File"); btn.setChangeListener(this); add(btn); } public void fieldChanged(Field field, int context) { if (field == btn) { try { InputStream inputStream = null; //Get File Connection FileConnection fileConnection = (FileConnection) Connector.open(path); if (fileConnection.exists()) { inputStream = fileConnection.openInputStream(); //byte data[]=inputStream.toString().getBytes(); ByteArrayOutputStream baos = new ByteArrayOutputStream(); int j = 0; while((j=inputStream.read()) != -1) { baos.write(j); } byte data[] = baos.toByteArray(); inputStream.close(); fileConnection.close(); WriteFile("file:///SDCard/BlackBerry/pictures/org_Image.jpg",data); EncodedImage eImage = EncodedImage.createEncodedImage(data,0,data.length); int scaleFactorX = Fixed32.div(Fixed32.toFP(eImage.getWidth()), Fixed32.toFP(80)); int scaleFactorY = Fixed32.div(Fixed32.toFP(eImage.getHeight()), Fixed32.toFP(80)); eImage=eImage.scaleImage32(scaleFactorX, scaleFactorY); WriteFile("file:///SDCard/BlackBerry/pictures/resize.jpg",eImage.getData()); BitmapField bit=new BitmapField(eImage.getBitmap()); add(bit); } } catch(Exception e) { System.out.println("Exception is ==> "+e.getMessage()); } } } void WriteFile(String fileName,byte[] data) { FileConnection fconn = null; try { fconn = (FileConnection) Connector.open(fileName,Connector.READ_WRITE); } catch (IOException e) { System.out.print("Error opening file"); } if (fconn.exists()) try { fconn.delete(); } catch (IOException e) { System.out.print("Error deleting file"); } try { fconn.create(); } catch (IOException e) { System.out.print("Error creating file"); } OutputStream out = null; try { out = fconn.openOutputStream(); } catch (IOException e) { System.out.print("Error opening output stream"); } try { out.write(data); } catch (IOException e) { System.out.print("Error writing to output stream"); } try { fconn.close(); } catch (IOException e) { System.out.print("Error closing file"); } } }

    Read the article

  • How safe is my safe rethrow?

    - by gustafc
    (Late edit: This question will hopefully be obsolete when Java 7 comes, because of the "final rethrow" feature which seems like it will be added.) Quite often, I find myself in situations looking like this: do some initialization try { do some work } catch any exception { undo initialization rethrow exception } In C# you can do it like this: InitializeStuff(); try { DoSomeWork(); } catch { UndoInitialize(); throw; } For Java, there's no good substitution, and since the proposal for improved exception handling was cut from Java 7, it looks like it'll take at best several years until we get something like it. Thus, I decided to roll my own: (Edit: Half a year later, final rethrow is back, or so it seems.) public final class Rethrow { private Rethrow() { throw new AssertionError("uninstantiable"); } /** Rethrows t if it is an unchecked exception. */ public static void unchecked(Throwable t) { if (t instanceof Error) throw (Error) t; if (t instanceof RuntimeException) throw (RuntimeException) t; } /** Rethrows t if it is an unchecked exception or an instance of E. */ public static <E extends Exception> void instanceOrUnchecked( Class<E> exceptionClass, Throwable t) throws E, Error, RuntimeException { Rethrow.unchecked(t); if (exceptionClass.isInstance(t)) throw exceptionClass.cast(t); } } Typical usage: public void doStuff() throws SomeException { initializeStuff(); try { doSomeWork(); } catch (Throwable t) { undoInitialize(); Rethrow.instanceOrUnchecked(SomeException.class, t); // We shouldn't get past the above line as only unchecked or // SomeException exceptions are thrown in the try block, but // we don't want to risk swallowing an error, so: throw new SomeException("Unexpected exception", t); } private void doSomeWork() throws SomeException { ... } } It's a bit wordy, catching Throwable is usually frowned upon, I'm not really happy at using reflection just to rethrow an exception, and I always feel a bit uneasy writing "this will not happen" comments, but in practice it works well (or seems to, at least). What I wonder is: Do I have any flaws in my rethrow helper methods? Some corner cases I've missed? (I know that the Throwable may have been caused by something so severe that my undoInitialize will fail, but that's OK.) Has someone already invented this? I looked at Commons Lang's ExceptionUtils but that does other things. Edit: finally is not the droid I'm looking for. I'm only interested to do stuff when an exception is thrown. Yes, I know catching Throwable is a big no-no, but I think it's the lesser evil here compared to having three catch clauses (for Error, RuntimeException and SomeException, respectively) with identical code. Note that I'm not trying to suppress any errors - the idea is that any exceptions thrown in the try block will continue to bubble up through the call stack as soon as I've rewinded a few things.

    Read the article

  • Fast ArgumentNullException with attributes. It is possible?

    - by Fraga
    Hi. Is there any fast way to verify null arguments via attributes or something? Convert this: public void Method(type arg1,type arg2,type arg3) { if (arg1== null) throw new ArgumentNullException("arg1"); if (arg2== null) throw new ArgumentNullException("arg2"); if (arg3== null) throw new ArgumentNullException("arg3"); //Business Logic } Into something like this: [VerifyNullArgument("arg1","arg2","arg3")] public void Method(type arg1,type arg2,type arg3) { //Business Logic } Ideas? thanks guys.

    Read the article

  • Unable to use nMock GetProperty routine on a property of an inherited object...

    - by Chris
    I am getting this error when trying to set an expectation on an object I mocked that inherits from MembershipUser: ContactRepositoryTests.UpdateTest : FailedSystem.InvalidProgramException: JIT Compiler encountered an internal limitation. Server stack trace: at MockObjectType1.ToString() Exception rethrown at [0]: at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg) at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(ref MessageData msgData, Int32 type) at System.Object.ToString() at NMock2.Internal.ExpectationBuilder.On(Object receiver) Here are the tools I am using... VS2008 (SP1) Framework 3.5 nUnit 2.4.8 nMock 2.0.0.44 Resharper 4.1 I am at a loss as to why this would be happening. Any help would be appreciated. Test Class... [TestFixture] public class AddressRepositoryTests { private Mockery m_Mockery; private Data.IAddress m_MockDataAddress; private IUser m_MockUser; [SetUp] public void Setup() { m_Mockery = new Mockery(); m_MockDataAddress = m_Mockery.NewMock<Data.IAddress>(); m_MockUser = m_Mockery.NewMock<IUser>(); } [TearDown] public void TearDown() { m_Mockery.Dispose(); } [Test] public void CreateTest() { string line1 = "unitTestLine1"; string line2 = "unitTestLine2"; string city = "unitTestCity"; int stateId = 1893; string postalCode = "unitTestPostalCode"; int countryId = 223; bool active = false; int createdById = 1; Expect.Once .On(m_MockUser) .GetProperty("Identity") .Will(Return.Value(createdById)); Expect.Once .On(m_MockDataAddress) .Method("Insert") .With( line1, line2, city, stateId, postalCode, countryId, active, createdById, Is.Anything ) .Will(Return.Value(null)); IAddressRepository addressRepository = new AddressRepository(m_MockDataAddress); IAddress address = addressRepository.Create( line1, line2, city, stateId, postalCode, countryId, active, m_MockUser ); Assert.IsNull(address); } } User Class... public interface IUser { int? Identity { get; set; } int? CreatedBy { get; set; } DateTime CreatedOn { get; set; } int? ModifiedBy { get; set; } DateTime? ModifiedOn { get; set; } string UserName { get; } object ProviderUserKey { get; } string Email { get; set; } string PasswordQuestion { get; } string Comment { get; set; } bool IsApproved { get; set; } bool IsLockedOut { get; } DateTime LastLockoutDate { get; } DateTime CreationDate { get; } DateTime LastLoginDate { get; set; } DateTime LastActivityDate { get; set; } DateTime LastPasswordChangedDate { get; } bool IsOnline { get; } string ProviderName { get; } string ToString(); string GetPassword(); string GetPassword(string passwordAnswer); bool ChangePassword(string oldPassword, string newPassword); bool ChangePasswordQuestionAndAnswer(string password, string newPasswordQuestion, string newPasswordAnswer); string ResetPassword(string passwordAnswer); string ResetPassword(); bool UnlockUser(); } public class User : MembershipUser, IUser { #region Public Properties private int? m_Identity; public int? Identity { get { return m_Identity; } set { if (value <= 0) throw new Exception("Address.Identity must be greater than 0."); m_Identity = value; } } public int? CreatedBy { get; set; } private DateTime m_CreatedOn = DateTime.Now; public DateTime CreatedOn { get { return m_CreatedOn; } set { m_CreatedOn = value; } } public int? ModifiedBy { get; set; } public DateTime? ModifiedOn { get; set; } #endregion Public Properties #region Public Constructors public User() { } #endregion Public Constructors } Address Class... public interface IAddress { int? Identity { get; set; } string Line1 { get; set; } string Line2 { get; set; } string City { get; set; } string PostalCode { get; set; } bool Active { get; set; } int? CreatedBy { get; set; } DateTime CreatedOn { get; set; } int? ModifiedBy { get; set; } DateTime? ModifiedOn { get; set; } } public class Address : IAddress { #region Public Properties private int? m_Identity; public int? Identity { get { return m_Identity; } set { if (value <= 0) throw new Exception("Address.Identity must be greater than 0."); m_Identity = value; } } public string Line1 { get; set; } public string Line2 { get; set; } public string City { get; set; } public string PostalCode { get; set; } public bool Active { get; set; } public int? CreatedBy { get; set; } private DateTime m_CreatedOn = DateTime.Now; public DateTime CreatedOn { get { return m_CreatedOn; } set { m_CreatedOn = value; } } public int? ModifiedBy { get; set; } public DateTime? ModifiedOn { get; set; } #endregion Public Properties } AddressRepository Class... public interface IAddressRepository { IAddress Create(string line1, string line2, string city, int stateId, string postalCode, int countryId, bool active, IUser createdBy); } public class AddressRepository : IAddressRepository { #region Private Properties private Data.IAddress m_DataAddress; private Data.IAddress DataAddress { get { if (m_DataAddress == null) m_DataAddress = new Data.Address(); return m_DataAddress; } set { m_DataAddress = value; } } #endregion Private Properties #region Public Constructor public AddressRepository() { } public AddressRepository(Data.IAddress dataAddress) { DataAddress = dataAddress; } #endregion Public Constructor #region Public Methods public IAddress Create(string line1, string line2, string city, int stateId, string postalCode, int countryId, bool active, IUser createdBy) { if (String.IsNullOrEmpty(line1)) throw new Exception("You must enter a Address Line 1 to register."); if (String.IsNullOrEmpty(city)) throw new Exception("You must enter a City to register."); if (stateId <= 0) throw new Exception("You must select a State to register."); if (String.IsNullOrEmpty(postalCode)) throw new Exception("You must enter a Postal Code to register."); if (countryId <= 0) throw new Exception("You must select a Country to register."); DataSet dataSet = DataAddress.Insert( line1, line2, city, stateId, postalCode, countryId, active, createdBy.Identity, DateTime.Now ); return null; } #endregion Public Methods } DataAddress Class... public interface IAddress { DataSet GetByAddressId (int? AddressId); DataSet Update (int? AddressId, string Address1, string Address2, string City, int? StateId, string PostalCode, int? CountryId, bool? IsActive, Guid? ModifiedBy); DataSet Insert (string Address1, string Address2, string City, int? StateId, string PostalCode, int? CountryId, bool? IsActive, int? CreatedBy, DateTime? CreatedOn); } public class Address : IAddress { public DataSet GetByAddressId (int? AddressId) { Database database = DatabaseFactory.CreateDatabase(); DbCommand dbCommand = database.GetStoredProcCommand("prAddress_GetByAddressId"); DataSet dataSet; try { database.AddInParameter(dbCommand, "AddressId", DbType.Int32, AddressId); dataSet = database.ExecuteDataSet(dbCommand); } catch (SqlException sqlException) { string callMessage = "prAddress_GetByAddressId " + "@AddressId = " + AddressId; throw new Exception(callMessage, sqlException); } return dataSet; } public DataSet Update (int? AddressId, string Address1, string Address2, string City, int? StateId, string PostalCode, int? CountryId, bool? IsActive, Guid? ModifiedBy) { Database database = DatabaseFactory.CreateDatabase(); DbCommand dbCommand = database.GetStoredProcCommand("prAddress_Update"); DataSet dataSet; try { database.AddInParameter(dbCommand, "AddressId", DbType.Int32, AddressId); database.AddInParameter(dbCommand, "Address1", DbType.AnsiString, Address1); database.AddInParameter(dbCommand, "Address2", DbType.AnsiString, Address2); database.AddInParameter(dbCommand, "City", DbType.AnsiString, City); database.AddInParameter(dbCommand, "StateId", DbType.Int32, StateId); database.AddInParameter(dbCommand, "PostalCode", DbType.AnsiString, PostalCode); database.AddInParameter(dbCommand, "CountryId", DbType.Int32, CountryId); database.AddInParameter(dbCommand, "IsActive", DbType.Boolean, IsActive); database.AddInParameter(dbCommand, "ModifiedBy", DbType.Guid, ModifiedBy); dataSet = database.ExecuteDataSet(dbCommand); } catch (SqlException sqlException) { string callMessage = "prAddress_Update " + "@AddressId = " + AddressId + ", @Address1 = " + Address1 + ", @Address2 = " + Address2 + ", @City = " + City + ", @StateId = " + StateId + ", @PostalCode = " + PostalCode + ", @CountryId = " + CountryId + ", @IsActive = " + IsActive + ", @ModifiedBy = " + ModifiedBy; throw new Exception(callMessage, sqlException); } return dataSet; } public DataSet Insert (string Address1, string Address2, string City, int? StateId, string PostalCode, int? CountryId, bool? IsActive, int? CreatedBy, DateTime? CreatedOn) { Database database = DatabaseFactory.CreateDatabase(); DbCommand dbCommand = database.GetStoredProcCommand("prAddress_Insert"); DataSet dataSet; try { database.AddInParameter(dbCommand, "Address1", DbType.AnsiString, Address1); database.AddInParameter(dbCommand, "Address2", DbType.AnsiString, Address2); database.AddInParameter(dbCommand, "City", DbType.AnsiString, City); database.AddInParameter(dbCommand, "StateId", DbType.Int32, StateId); database.AddInParameter(dbCommand, "PostalCode", DbType.AnsiString, PostalCode); database.AddInParameter(dbCommand, "CountryId", DbType.Int32, CountryId); database.AddInParameter(dbCommand, "IsActive", DbType.Boolean, IsActive); database.AddInParameter(dbCommand, "CreatedBy", DbType.Int32, CreatedBy); database.AddInParameter(dbCommand, "CreatedOn", DbType.DateTime, CreatedOn); dataSet = database.ExecuteDataSet(dbCommand); } catch (SqlException sqlException) { string callMessage = "prAddress_Insert " + "@Address1 = " + Address1 + ", @Address2 = " + Address2 + ", @City = " + City + ", @StateId = " + StateId + ", @PostalCode = " + PostalCode + ", @CountryId = " + CountryId + ", @IsActive = " + IsActive + ", @CreatedBy = " + CreatedBy + ", @CreatedOn = " + CreatedOn; throw new Exception(callMessage, sqlException); } return dataSet; } }

    Read the article

  • Restore previously serialized JFrame-object, how?

    - by elementz
    Hi all. I have managed to serialize my very basic GUI-object containing a JTextArea and a few buttons to a file 'test.ser'. Now, I would like to completely restore the previously saved state from 'test.ser', but seem to have a misconception of how to properly deserialize an objects state. The class MyFrame creates the JFrame and serializes it. public class MyFrame extends JFrame implements ActionListener { // Fields JTextArea textArea; String title; static MyFrame gui = new MyFrame(); private static final long serialVersionUID = 1125762532137824262L; /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub gui.run(); } // parameterless default contructor public MyFrame() { } // constructor with title public MyFrame(String title) { } // creates Frame and its Layout public void run() { JFrame frame = new JFrame(title); JPanel panel_01 = new JPanel(); JPanel panel_02 = new JPanel(); JTextArea textArea = new JTextArea(20, 22); textArea.setLineWrap(true); JScrollPane scrollPane = new JScrollPane(textArea); scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED); panel_01.add(scrollPane); // Buttons JButton saveButton = new JButton("Save"); saveButton.addActionListener(this); JButton loadButton = new JButton("Load"); loadButton.addActionListener(this); panel_02.add(loadButton); panel_02.add(saveButton); // Layout frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.getContentPane().add(BorderLayout.CENTER, panel_01); frame.getContentPane().add(BorderLayout.SOUTH, panel_02); frame.setSize(300, 400); frame.setVisible(true); } /* * */ public void serialize() { try { ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("test.ser")); oos.writeObject(gui); oos.close(); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } } public void actionPerformed(ActionEvent ev) { System.out.println("Action received!"); gui.serialize(); } } Here I try to do the deserialization: public class Deserialize { static Deserialize ds; static MyFrame frame; public static void main(String[] args) { try { ObjectInputStream ois = new ObjectInputStream(new FileInputStream("test.ser")); frame = (MyFrame) ois.readObject(); ois.close(); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } } Maybe somebody could point me into the direction where my misconception is? Thx in advance!

    Read the article

< Previous Page | 38 39 40 41 42 43 44 45 46 47 48 49  | Next Page >