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  • android alarm not able to launch alarm activity

    - by user965830
    I am new to android programming and am trying to make this simple alarm app. I have my code written and it is compiled with no errors. The app runs in the emulator, that is the main activity asks the date and time, but when i click on the confirm button, it displays the message - "Unfortunately, Timer1 has stopped working." The code for my main activity is as follows: public void onClick(View v) { EditText date = (EditText) findViewById(R.id.editDate); EditText month = (EditText) findViewById(R.id.editMonth); EditText hour = (EditText) findViewById(R.id.editHour); EditText min = (EditText) findViewById(R.id.editMin); int dt = Integer.parseInt(date.getText().toString()); int mon = Integer.parseInt(month.getText().toString()); int hr = Integer.parseInt(hour.getText().toString()); int mnt = Integer.parseInt(min.getText().toString()); Intent myIntent = new Intent(MainActivity.this, AlarmActivity.class); pendingIntent = PendingIntent.getService(MainActivity.this, 0, myIntent, 0); AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE); Calendar calendar = Calendar.getInstance(); calendar.set(Calendar.DATE, dt); calendar.set(Calendar.MONTH, mon); calendar.set(Calendar.HOUR, hr); calendar.set(Calendar.MINUTE, mnt); alarmManager.set(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), pendingIntent); } I do not understand what all the errors in logcat mean, so i am posting them: 06-25 16:03:32.175: I/Process(566): Sending signal. PID: 566 SIG: 9 06-25 16:03:53.775: I/dalvikvm(612): threadid=3: reacting to signal 3 06-25 16:03:54.046: I/dalvikvm(612): Wrote stack traces to '/data/anr/traces.txt' 06-25 16:03:54.255: I/dalvikvm(612): threadid=3: reacting to signal 3 06-25 16:03:54.305: I/dalvikvm(612): Wrote stack traces to '/data/anr/traces.txt' 06-25 16:03:54.735: I/dalvikvm(612): threadid=3: reacting to signal 3 06-25 16:03:54.785: I/dalvikvm(612): Wrote stack traces to '/data/anr/traces.txt' 06-25 16:03:54.925: D/gralloc_goldfish(612): Emulator without GPU emulation detected. 06-25 16:05:09.605: D/AndroidRuntime(612): Shutting down VM 06-25 16:05:09.605: W/dalvikvm(612): threadid=1: thread exiting with uncaught exception (group=0x409c01f8) 06-25 16:05:09.685: E/AndroidRuntime(612): FATAL EXCEPTION: main 06-25 16:05:09.685: E/AndroidRuntime(612): java.lang.NumberFormatException: Invalid int: "android.widget.EditText@41030b40" 06-25 16:05:09.685: E/AndroidRuntime(612): at java.lang.Integer.invalidInt(Integer.java:138) 06-25 16:05:09.685: E/AndroidRuntime(612): at java.lang.Integer.parse(Integer.java:375) 06-25 16:05:09.685: E/AndroidRuntime(612): at java.lang.Integer.parseInt(Integer.java:366) 06-25 16:05:09.685: E/AndroidRuntime(612): at java.lang.Integer.parseInt(Integer.java:332) 06-25 16:05:09.685: E/AndroidRuntime(612): at com.kapymay.tversion1.MainActivity$1.onClick(MainActivity.java:34) 06-25 16:05:09.685: E/AndroidRuntime(612): at android.view.View.performClick(View.java:3511) 06-25 16:05:09.685: E/AndroidRuntime(612): at android.view.View$PerformClick.run(View.java:14105) 06-25 16:05:09.685: E/AndroidRuntime(612): at android.os.Handler.handleCallback(Handler.java:605) 06-25 16:05:09.685: E/AndroidRuntime(612): at android.os.Handler.dispatchMessage(Handler.java:92) 06-25 16:05:09.685: E/AndroidRuntime(612): at android.os.Looper.loop(Looper.java:137) 06-25 16:05:09.685: E/AndroidRuntime(612): at android.app.ActivityThread.main(ActivityThread.java:4424) 06-25 16:05:09.685: E/AndroidRuntime(612): at java.lang.reflect.Method.invokeNative(Native Method) 06-25 16:05:09.685: E/AndroidRuntime(612): at java.lang.reflect.Method.invoke(Method.java:511) 06-25 16:05:09.685: E/AndroidRuntime(612): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 06-25 16:05:09.685: E/AndroidRuntime(612): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 06-25 16:05:09.685: E/AndroidRuntime(612): at dalvik.system.NativeStart.main(Native Method) 06-25 16:05:10.445: I/dalvikvm(612): threadid=3: reacting to signal 3 06-25 16:05:10.575: I/dalvikvm(612): Wrote stack traces to '/data/anr/traces.txt'

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  • WCF Troubleshooting from ASP.NET Client -- Help!

    - by Kobojunkie
    I am trying to call a method in my service that is as below, from an ASP.NET application. public bool ValidateUser(string username, string password) { try { // String CurrentLoggedInWindowsUserName = WindowsIdentity.GetCurrent().Name; // //primary identity of the call // String CurrentServiceSecurityContextPrimaryIdentityName = // ServiceSecurityContext.Current.PrimaryIdentity.Name; // } catch (Exception ex) { FaultExceptionFactory fct = new FaultExceptionFactory(); throw new FaultException<CustomFaultException>(fct.CreateFaultException(ex)); } return false; } The Config for the client end of my service is as below <binding name="WSHttpBinding_IMembershipService" closeTimeout="00:01:00" openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00" bypassProxyOnLocal="false" transactionFlow="false" hostNameComparisonMode="StrongWildcard" maxBufferPoolSize="524288" maxReceivedMessageSize="65536" messageEncoding="Text" textEncoding="utf-8" useDefaultWebProxy="false" allowCookies="false"> <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384" maxBytesPerRead="4096" maxNameTableCharCount="16384" /> <reliableSession ordered="true" inactivityTimeout="00:10:00" enabled="false" /> <security mode="Message"> <transport clientCredentialType="Windows" proxyCredentialType="None" realm="" /> <message clientCredentialType="Windows" negotiateServiceCredential="true" algorithmSuite="Default" establishSecurityContext="true" /> </security> </binding> Problem I keep having is when I call it; I get the following exception message. Server Error in '/' Application. The communication object, System.ServiceModel.Channels.ServiceChannel, cannot be used for communication because it is in the Faulted state. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.ServiceModel.CommunicationObjectFaultedException: The communication object, System.ServiceModel.Channels.ServiceChannel, cannot be used for communication because it is in the Faulted state. Stack Trace: [CommunicationObjectFaultedException: The communication object, System.ServiceModel.Channels.ServiceChannel, cannot be used for communication because it is in the Faulted state.] System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg) +7596735 System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type) +275 System.ServiceModel.ICommunicationObject.Close(TimeSpan timeout) +0 System.ServiceModel.ClientBase`1.System.ServiceModel.ICommunicationObject. Close(TimeSpan timeout) +142 System.ServiceModel.ClientBase`1.Close() +38 System.ServiceModel.ClientBase`1.System.IDisposable.Dispose() +4 Controls.Membership.accountLogin.ValidateUserCredentials(String UserName, String Password) in C:\ Petition.WebClient\Controls\ Membership\accountLogin.ascx.cs:49 Controls.Membership.accountLogin.Login1_Authenticate(Object sender, AuthenticateEventArgs e) in C:\ WebClient\ Controls\Membership \accountLogin.ascx.cs:55 I am not entirely sure why I keep getting this. Just in case, here is how I call my service from the client private bool ValidateUserCredentials(string UserName, string Password) { bool boolReturnValue = false; using(Members.MembershipServiceClient client = new Controls.Members.MembershipServiceClient()) { try { boolReturnValue = client.ValidateUser(UserName, Password); } catch (FaultException<CustomFaultException> ex) { throw ex; } } return boolReturnValue; } Anyone have any idea what I need to do in this case?

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  • derby + hibernate ConstraintViolationException using manytomany relationships

    - by user364470
    Hi, I'm new to Hibernate+Derby... I've seen this issue mentioned throughout the google, but have not seen a proper resolution. This following code works fine with mysql, but when I try this on derby i get exceptions: ( each Tag has two sets of files and vise-versa - manytomany) Tags.java @Entity @Table(name="TAGS") public class Tags implements Serializable { @Id @GeneratedValue(strategy=GenerationType.AUTO) public long getId() { return id; } @ManyToMany(targetEntity=Files.class ) @ForeignKey(name="USER_TAGS_FILES",inverseName="USER_FILES_TAGS") @JoinTable(name="USERTAGS_FILES", joinColumns=@JoinColumn(name="TAGS_ID"), inverseJoinColumns=@JoinColumn(name="FILES_ID")) public Set<data.Files> getUserFiles() { return userFiles; } @ManyToMany(mappedBy="autoTags", targetEntity=data.Files.class) public Set<data.Files> getAutoFiles() { return autoFiles; } Files.java @Entity @Table(name="FILES") public class Files implements Serializable { @Id @GeneratedValue(strategy=GenerationType.AUTO) public long getId() { return id; } @ManyToMany(mappedBy="userFiles", targetEntity=data.Tags.class) public Set getUserTags() { return userTags; } @ManyToMany(targetEntity=Tags.class ) @ForeignKey(name="AUTO_FILES_TAGS",inverseName="AUTO_TAGS_FILES") @JoinTable(name="AUTOTAGS_FILES", joinColumns=@JoinColumn(name="FILES_ID"), inverseJoinColumns=@JoinColumn(name="TAGS_ID")) public Set getAutoTags() { return autoTags; } I add some data to the DB, but when running over Derby these exception turn up (the don't using mysql) Exceptions SEVERE: DELETE on table 'FILES' caused a violation of foreign key constraint 'USER_FILES_TAGS' for key (3). The statement has been rolled back. Jun 10, 2010 9:49:52 AM org.hibernate.event.def.AbstractFlushingEventListener performExecutions SEVERE: Could not synchronize database state with session org.hibernate.exception.ConstraintViolationException: could not delete: [data.Files#3] at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:96) at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66) at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2712) at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:2895) at org.hibernate.action.EntityDeleteAction.execute(EntityDeleteAction.java:97) at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:268) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:260) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:184) at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321) at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:51) at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1206) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:613) at org.hibernate.context.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:344) at $Proxy13.flush(Unknown Source) at data.HibernateORM.removeFile(HibernateORM.java:285) at data.DataImp.removeFile(DataImp.java:195) at booting.DemoBootForTestUntilTestClassesExist.main(DemoBootForTestUntilTestClassesExist.java:62) I have never used derby before so maybe there is something crutal that i'm missing 1) what am I doing wrong? 2) is there any way of cascading properly when I have 2 many-to-many relationships between two classes? Thanks!

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  • Java EE javax.xml.bind.MarshalException

    - by sandeep
    Hi, I am getting javax.xml.bind.MarshalException error. I am sending List from my webservice to the backingbean and I have this error. WARNING: invocation error on ejb endpoint Login_webservice at /Login_webserviceService/Login_webservice : javax.xml.bind.MarshalException - with linked exception: [javax.xml.bind.JAXBException: class JPA.Cantable nor any of its super class is known to this context.] javax.xml.ws.WebServiceException: javax.xml.bind.MarshalException - with linked exception: [javax.xml.bind.JAXBException: class JPA.Cantable nor any of its super class is known to this context.] at com.sun.xml.ws.message.jaxb.JAXBMessage.writePayloadTo(JAXBMessage.java:325) at com.sun.xml.ws.message.AbstractMessageImpl.writeTo(AbstractMessageImpl.java:142) at com.sun.xml.ws.encoding.StreamSOAPCodec.encode(StreamSOAPCodec.java:109) at com.sun.xml.ws.encoding.SOAPBindingCodec.encode(SOAPBindingCodec.java:278) at com.sun.xml.ws.transport.http.HttpAdapter.encodePacket(HttpAdapter.java:380) at com.sun.xml.ws.transport.http.HttpAdapter.access$100(HttpAdapter.java:92) at com.sun.xml.ws.transport.http.HttpAdapter$HttpToolkit.handle(HttpAdapter.java:525) at com.sun.xml.ws.transport.http.HttpAdapter.handle(HttpAdapter.java:285) at com.sun.xml.ws.transport.http.servlet.ServletAdapter.handle(ServletAdapter.java:143) at org.glassfish.webservices.Ejb3MessageDispatcher.handlePost(Ejb3MessageDispatcher.java:116) at org.glassfish.webservices.Ejb3MessageDispatcher.invoke(Ejb3MessageDispatcher.java:87) at org.glassfish.webservices.EjbWebServiceServlet.dispatchToEjbEndpoint(EjbWebServiceServlet.java:196) at org.glassfish.webservices.EjbWebServiceServlet.service(EjbWebServiceServlet.java:127) at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) Here is my code: Backing bean @WebServiceRef(wsdlLocation = "http://localhost:26565/Login_webserviceService/Login_webservice?WSDL") public String login() { System.out.println("Login Phase entered"); int result = 0; List list; List finalList = null; try { Weblogin.LoginWebserviceService service = new Weblogin.LoginWebserviceService(); Weblogin.LoginWebservice port = service.getLoginWebservicePort(); result = port.login(voterID, password); Weblogin.LoginWebservice port1 = service.getLoginWebservicePort(); list = port1.candDetails(1); finalList = list; this.setList(finalList); } catch (Exception e) { e.printStackTrace(); } if (result == 1) return "polling"; else return "login"; } Webservice public List candDetails(int pollEvent) { List resultList = null; List finalList = null; try { if (pollEvent == 1) { resultList = em.createNamedQuery("Cantable.findAll").getResultList(); finalList = resultList; } } catch (Exception e) { e.printStackTrace(); } return resultList; }

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  • how to load external xml using air application for flash programmer ?

    - by Ayman
    hi, i have faced this problem couple of days ago, while trying to import an external xml file into an AIR application. import flash.net.URLRequest; var ldr:Loader = new Loader(); var url:String = "http://willperone.net/rss.php"; var urlReq:URLRequest = new URLRequest(url); ldr.load(urlReq); ldr.addEventListener(Event.COMPLETE , function(e) { trace('Wow, completed ...'); }); ldr.contentLoaderInfo.addEventListener(IOErrorEvent.IO_ERROR, function(e) { trace('IO_ERROR'); }); and always the IO_ERROR shows up. may i do it wrong or something needs a little of configuration, so please help

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  • SWT on Windows 64-bit

    - by Palani
    My application throws the exception below. Exception in thread "main" java.lang.UnsatisfiedLinkError: Cannot load 32-bit SW T libraries on 64-bit JVM. How to solve this? What is the name of jar file needed?

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  • How can I refactor client side functionality to create a product line-like generic design?

    - by Nupul
    Assume the following situation similar to that of Stack Overflow: I have a system with a front-end that can perform various manipulations on the data (by sending messages to REST back-end): Posting Editing and deleting Adding labels and tags Now in the first version we created it well modularized but the need as of now for 'evolving' the system similar to Stack Overflow. My question is how best to separate the commonality and how to incorporate the variability with respect to the following: Commonality: The above 'functionalities' and sending/receiving the data from the server Look and feel (also a variability as explained below) HTTP verbs associated with the above actions Variability: The RESTful URLs where the requests are sent The text/style of the UI (the commonality is analogous to Stack Overflow - the functionality of upvotes, posting a question remains the same, but the words, the icons, the look and feel is still different across sites) I think this is entirely a client-side code organization/refactoring issue. I'm heavily using jQuery, javascript and backbone for front-end development. My question is how best should I isolate the same to be able to create multiple such aspects to the tool we are currently working on?

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  • C++/msvc6 application crashes due to heap corruption, any hints?

    - by David Alfonso
    Hello all, let me say first that I'm writing this question after months of trying to find out the root of a crash happening in our application. I'll try to detail as much as possible what I've already found out about it. About the application It runs on Windows XP Professional SP2. It's built with Microsoft Visual C++ 6.0 with Service Pack 6. It's MFC based. It uses several external dlls (e.g. Xerces, ZLib or ACE). It has high performance requirements. It does a lot of network and hard disk I/O, but it's also cpu intensive. It has an exception handling mechanism which generates a minidump when an unhandled exception occurs. Facts about the crash It only happens on multiprocessor/multicore machines and under heavy loads of work. It happens at random (neither we nor our client have found a pattern yet). We cannot reproduce the crash on our testing lab. It only happens on some production systems (but always in multicore machines) It always ends up crashing at the same point, although the complete stack is not always the same. Let me add the stack of the crashing thread (obtained using WinDbg, sorry we don't have symbols) ChildEBP RetAddr Args to Child WARNING: Stack unwind information not available. Following frames may be wrong. 030af6c8 7c9206eb 77bfc3c9 01a80000 00224bc3 MyApplication+0x2a85b9 030af960 7c91e9c0 7c92901b 00000ab4 00000000 ntdll!RtlAllocateHeap+0xeac (FPO: [Non-Fpo]) 030af98c 7c9205c8 00000001 00000000 00000000 ntdll!ZwWaitForSingleObject+0xc (FPO: [3,0,0]) 030af9c0 7c920551 01a80898 7c92056d 313adfb0 ntdll!RtlpFreeToHeapLookaside+0x22 (FPO: [2,0,4]) 030afa8c 4ba3ae96 000307da 00130005 00040012 ntdll!RtlFreeHeap+0x1e9 (FPO: [Non-Fpo]) 030afacc 77bfc2e3 0214e384 3087c8d8 02151030 0x4ba3ae96 030afb00 7c91e306 7c80bfc1 00000948 00000001 msvcrt!free+0xc8 (FPO: [Non-Fpo]) 030afb20 0042965b 030afcc0 0214d780 02151218 ntdll!ZwReleaseSemaphore+0xc (FPO: [3,0,0]) 030afb7c 7c9206eb 02e6c471 02ea0000 00000008 MyApplication+0x2965b 030afe60 7c9205c8 02151248 030aff38 7c920551 ntdll!RtlAllocateHeap+0xeac (FPO: [Non-Fpo]) 030afe74 7c92056d 0210bfb8 02151250 02151250 ntdll!RtlpFreeToHeapLookaside+0x22 (FPO: [2,0,4]) 030aff38 77bfc2de 01a80000 00000000 77bfc2e3 ntdll!RtlFreeHeap+0x647 (FPO: [Non-Fpo]) 7c92056d c5ffffff ce7c94be ff7c94be 00ffffff msvcrt!free+0xc3 (FPO: [Non-Fpo]) 7c920575 ff7c94be 00ffffff 12000000 907c94be 0xc5ffffff 7c920579 00ffffff 12000000 907c94be 90909090 0xff7c94be *** WARNING: Unable to verify checksum for xerces-c_2_7.dll *** ERROR: Symbol file could not be found. Defaulted to export symbols for xerces-c_2_7.dll - 7c92057d 12000000 907c94be 90909090 8b55ff8b MyApplication+0xbfffff 7c920581 907c94be 90909090 8b55ff8b 08458bec xerces_c_2_7 7c920585 90909090 8b55ff8b 08458bec 04408b66 0x907c94be 7c920589 8b55ff8b 08458bec 04408b66 0004c25d 0x90909090 7c92058d 08458bec 04408b66 0004c25d 90909090 0x8b55ff8b The address MyApplication+0x2a85b9 corresponds to a call to erase() of a std::list. What I have tried so far Reviewing all the code related to the point where the crash ends happening. Trying to enable pageheap on our testing lab though nothing useful has been found by now. We have substituted the std::list for a C array and then it crashes in other part of the code (although it is related code, it's not in the code where the old list resided). Coincidentally, now it crashes in another erase, though this time of a std::multiset. Let me copy the stack contained in the dump: ntdll.dll!_RtlpCoalesceFreeBlocks@16() + 0x124e bytes ntdll.dll!_RtlFreeHeap@12() + 0x91f bytes msvcrt.dll!_free() + 0xc3 bytes MyApplication.exe!006a4fda() [Frames below may be incorrect and/or missing, no symbols loaded for MyApplication.exe] MyApplication.exe!0069f305() ntdll.dll!_NtFreeVirtualMemory@16() + 0xc bytes ntdll.dll!_RtlpSecMemFreeVirtualMemory@16() + 0x1b bytes ntdll.dll!_ZwWaitForSingleObject@12() + 0xc bytes ntdll.dll!_RtlpFreeToHeapLookaside@8() + 0x26 bytes ntdll.dll!_RtlFreeHeap@12() + 0x114 bytes msvcrt.dll!_free() + 0xc3 bytes c5ffffff() Possible solutions (that I'm aware of) which cannot be applied "Migrate the application to a newer compiler": We are working on this but It's not a solution at the moment. "Enable pageheap (normal or full)": We can't enable pageheap on production machines as this affects performance heavily. I think that's all I remember now, if I have forgotten something I'll add it asap. If you can give me some hint or propose some possible solution, don't hesitate to answer! Thank you in advance for your time and advice.

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  • WinForms: Why do I get InvalidCastException when showing folder browser dialog?

    - by Marek
    I am randomly getting InvalidCastException when showing FolderBrowserDialog and also many clients have reported this. I have not been able to find anything relevant on the internet. Does anyone know what causes this/how to fix this? My code: using (FolderBrowserDialog fbd = new FolderBrowserDialog()) { fbd.ShowNewFolderButton = false; if (fbd.ShowDialog() == DialogResult.OK) Stack trace: Error: System.InvalidCastException: 'Unable to cast object of type 'System.__ComObject' to type 'IMalloc'.'. Stack trace: at System.Windows.Forms.UnsafeNativeMethods.Shell32.SHGetMalloc(IMalloc[] ppMalloc) at System.Windows.Forms.FolderBrowserDialog.GetSHMalloc() at System.Windows.Forms.FolderBrowserDialog.RunDialog(IntPtr hWndOwner) at System.Windows.Forms.CommonDialog.ShowDialog(IWin32Window owner) at System.Windows.Forms.CommonDialog.ShowDialog() EDIT: Additional information: I have been able to reproduce this only when running in VS2008 debugger. When running out of debugger, it happens only very rarely (happened once or twice in 6 months) on my 64 bit Windows 7 and goes away after restart. The clients are certainly not running the app in debugger so it is surely reproducible out of debugger.

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  • .NET Security Part 4

    - by Simon Cooper
    Finally, in this series, I am going to cover some of the security issues that can trip you up when using sandboxed appdomains. DISCLAIMER: I am not a security expert, and this is by no means an exhaustive list. If you actually are writing security-critical code, then get a proper security audit of your code by a professional. The examples below are just illustrations of the sort of things that can go wrong. 1. AppDomainSetup.ApplicationBase The most obvious one is the issue covered in the MSDN documentation on creating a sandbox, in step 3 – the sandboxed appdomain has the same ApplicationBase as the controlling appdomain. So let’s explore what happens when they are the same, and an exception is thrown. In the sandboxed assembly, Sandboxed.dll (IPlugin is an interface in a partially-trusted assembly, with a single MethodToDoThings on it): public class UntrustedPlugin : MarshalByRefObject, IPlugin { // implements IPlugin.MethodToDoThings() public void MethodToDoThings() { throw new EvilException(); } } [Serializable] internal class EvilException : Exception { public override string ToString() { // show we have read access to C:\Windows // read the first 5 directories Console.WriteLine("Pwned! Mwuahahah!"); foreach (var d in Directory.EnumerateDirectories(@"C:\Windows").Take(5)) { Console.WriteLine(d.FullName); } return base.ToString(); } } And in the controlling assembly: // what can possibly go wrong? AppDomainSetup appDomainSetup = new AppDomainSetup { ApplicationBase = AppDomain.CurrentDomain.SetupInformation.ApplicationBase } // only grant permissions to execute // and to read the application base, nothing else PermissionSet restrictedPerms = new PermissionSet(PermissionState.None); restrictedPerms.AddPermission( new SecurityPermission(SecurityPermissionFlag.Execution)); restrictedPerms.AddPermission( new FileIOPermission(FileIOPermissionAccess.Read, appDomainSetup.ApplicationBase); restrictedPerms.AddPermission( new FileIOPermission(FileIOPermissionAccess.pathDiscovery, appDomainSetup.ApplicationBase); // create the sandbox AppDomain sandbox = AppDomain.CreateDomain("Sandbox", null, appDomainSetup, restrictedPerms); // execute UntrustedPlugin in the sandbox // don't crash the application if the sandbox throws an exception IPlugin o = (IPlugin)sandbox.CreateInstanceFromAndUnwrap("Sandboxed.dll", "UntrustedPlugin"); try { o.MethodToDoThings() } catch (Exception e) { Console.WriteLine(e.ToString()); } And the result? Oops. We’ve allowed a class that should be sandboxed to execute code with fully-trusted permissions! How did this happen? Well, the key is the exact meaning of the ApplicationBase property: The application base directory is where the assembly manager begins probing for assemblies. When EvilException is thrown, it propagates from the sandboxed appdomain into the controlling assembly’s appdomain (as it’s marked as Serializable). When the exception is deserialized, the CLR finds and loads the sandboxed dll into the fully-trusted appdomain. Since the controlling appdomain’s ApplicationBase directory contains the sandboxed assembly, the CLR finds and loads the assembly into a full-trust appdomain, and the evil code is executed. So the problem isn’t exactly that the sandboxed appdomain’s ApplicationBase is the same as the controlling appdomain’s, it’s that the sandboxed dll was in such a place that the controlling appdomain could find it as part of the standard assembly resolution mechanism. The sandbox then forced the assembly to load in the controlling appdomain by throwing a serializable exception that propagated outside the sandbox. The easiest fix for this is to keep the sandbox ApplicationBase well away from the ApplicationBase of the controlling appdomain, and don’t allow the sandbox permissions to access the controlling appdomain’s ApplicationBase directory. If you do this, then the sandboxed assembly can’t be accidentally loaded into the fully-trusted appdomain, and the code can’t be executed. If the plugin does try to induce the controlling appdomain to load an assembly it shouldn’t, a SerializationException will be thrown when it tries to load the assembly to deserialize the exception, and no damage will be done. 2. Loading the sandboxed dll into the application appdomain As an extension of the previous point, you shouldn’t directly reference types or methods in the sandboxed dll from your application code. That loads the assembly into the fully-trusted appdomain, and from there code in the assembly could be executed. Instead, pull out methods you want the sandboxed dll to have into an interface or class in a partially-trusted assembly you control, and execute methods via that instead (similar to the example above with the IPlugin interface). If you need to have a look at the assembly before executing it in the sandbox, either examine the assembly using reflection from within the sandbox, or load the assembly into the Reflection-only context in the application’s appdomain. The code in assemblies in the reflection-only context can’t be executed, it can only be reflected upon, thus protecting your appdomain from malicious code. 3. Incorrectly asserting permissions You should only assert permissions when you are absolutely sure they’re safe. For example, this method allows a caller read-access to any file they call this method with, including your documents, any network shares, the C:\Windows directory, etc: [SecuritySafeCritical] public static string GetFileText(string filePath) { new FileIOPermission(FileIOPermissionAccess.Read, filePath).Assert(); return File.ReadAllText(filePath); } Be careful when asserting permissions, and ensure you’re not providing a loophole sandboxed dlls can use to gain access to things they shouldn’t be able to. Conclusion Hopefully, that’s given you an idea of some of the ways it’s possible to get past the .NET security system. As I said before, this post is not exhaustive, and you certainly shouldn’t base any security-critical applications on the contents of this blog post. What this series should help with is understanding the possibilities of the security system, and what all the security attributes and classes mean and what they are used for, if you were to use the security system in the future.

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  • Java.lang.reflext.Proxy returning another proxy from invocation results in ClassCastException on ass

    - by matao
    So I'm playing with geotools and I thought I'd proxy one of their data-access classes and trace how it was being used in their code. I coded up a dynamic proxy and wrapped a FeatureSource (interface) in it and off it went happily. Then I wanted to look at some of the transitive objects returned by the featureSource as well, since the main thing a FeatureSource does is return a FeatureCollection (FeatureSource is analogous to a sql DataSource and featurecollection to an sql statement). in my invocationhandler I just passed the call through to the underlying object, printing out the target class/method/args and result as I went, but for calls that returned a FeatureCollection (another interface), I wrapped that object in my proxy (the same class but a new instance, shouldn't matter should it?) and returned it. BAM! Classcast exception: java.lang.ClassCastException: $Proxy5 cannot be cast to org.geotools.feature.FeatureCollection at $Proxy4.getFeatures(Unknown Source) at MyClass.myTestMethod(MyClass.java:295) the calling code: FeatureSource<SimpleFeatureType, SimpleFeature> featureSource = ... // create the FS featureSource = (FeatureSource<SimpleFeatureType, SimpleFeature>) FeatureSourceProxy.newInstance(featureSource, features); featureSource.getBounds();// ok featureSource.getSupportedHints();// ok DefaultQuery query1 = new DefaultQuery(DefaultQuery.ALL); FeatureCollection<SimpleFeatureType, SimpleFeature> results = featureSource.getFeatures(query1); //<- explosion here the Proxy: public class FeatureSourceProxy implements java.lang.reflect.InvocationHandler { private Object target; private List<SimpleFeature> features; public static Object newInstance(Object obj, List<SimpleFeature> features) { return java.lang.reflect.Proxy.newProxyInstance( obj.getClass().getClassLoader(), obj.getClass().getInterfaces(), new FeatureSourceProxy(obj, features) ); } private FeatureSourceProxy(Object obj, List<SimpleFeature> features) { this.target = obj; this.features = features; } public Object invoke(Object proxy, Method m, Object[] args)throws Throwable{ Object result = null; try { if("getFeatures".equals(m.getName())){ result = interceptGetFeatures(m, args); } else{ result = m.invoke(target, args); } } catch (Exception e) { throw new RuntimeException("unexpected invocation exception: " + e.getMessage(), e); } return result; } private Object interceptGetFeatures(Method m, Object[] args) throws Exception{ return newInstance(m.invoke(target, args), features); } } Is it possible to dynamically return proxies of interfaces from a proxied interface or am I doing something wrong? cheers!

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  • Understanding SingleTableEntityPersister n QueryLoader

    - by Iapilgrim
    Hi, I have the Hibernate model @Cache(usage = CacheConcurrencyStrategy.NONE, region = SitesConstants.CACHE_REGION) public class Node extends StatefulEntity implements Inheritable, Cloneable { private Node _parent; private List<Node> _childNodes; .. } @Cache(usage = CacheConcurrencyStrategy.NONE, region = SitesConstants.CACHE_REGION) public class Page extends Node implements Defaultable, Securable { private RootZone _rootZone; ...... @OneToOne(fetch = FetchType.LAZY) @JoinColumn(name = "root_zone_id", insertable = false, updatable = false) public RootZone getRootZone() { return _rootZone; } public void setRootZone(RootZone rootZone) { if (rootZone != null) { rootZone.setPageId(this.getId()); _rootZone = rootZone; } } I want to get all pages ( call getSiteTree), so I using this query String hpql = "SELECT n FROM Node n "; See the trace I find Page.setRootZone(RootZone) line: 155 NativeMethodAccessorImpl.invoke0(Method, Object, Object[]) line: not available [native method] NativeMethodAccessorImpl.invoke(Object, Object[]) line: 39 DelegatingMethodAccessorImpl.invoke(Object, Object[]) line: 25 Method.invoke(Object, Object...) line: 597 BasicPropertyAccessor$BasicSetter.set(Object, Object, SessionFactoryImplementor) line: 66 PojoEntityTuplizer(AbstractEntityTuplizer).setPropertyValues(Object, Object[]) line: 352 PojoEntityTuplizer.setPropertyValues(Object, Object[]) line: 232 SingleTableEntityPersister(AbstractEntityPersister).setPropertyValues(Object, Object[], EntityMode) line: 3580 TwoPhaseLoad.initializeEntity(Object, boolean, SessionImplementor, PreLoadEvent, PostLoadEvent) line: 152 QueryLoader(Loader).initializeEntitiesAndCollections(List, Object, SessionImplementor, boolean) line: 877 QueryLoader(Loader).doQuery(SessionImplementor, QueryParameters, boolean) line: 752 QueryLoader(Loader).doQueryAndInitializeNonLazyCollections(SessionImplementor, QueryParameters, boolean) line: 259 QueryLoader(Loader).doList(SessionImplementor, QueryParameters) line: 2232 QueryLoader(Loader).listIgnoreQueryCache(SessionImplementor, QueryParameters) line: 2129 QueryLoader(Loader).list(SessionImplementor, QueryParameters, Set, Type[]) line: 2124 QueryLoader.list(SessionImplementor, QueryParameters) line: 401 QueryTranslatorImpl.list(SessionImplementor, QueryParameters) line: 363 HQLQueryPlan.performList(QueryParameters, SessionImplementor) line: 196 SessionImpl.list(String, QueryParameters) line: 1149 QueryImpl.list() line: 102 QueryImpl.getResultList() line: 67 NodeDaoImpl.getSiteTree(long) line: 358 PageNodeServiceImpl.getSiteTree(long) line: 797 NativeMethodAccessorImpl.invoke0(Method, Object, Object[]) line: not available [native method] NativeMethodAccessorImpl.invoke(Object, Object[]) line: 39 DelegatingMethodAccessorImpl.invoke(Object, Object[]) line: 25 Method.invoke(Object, Object...) line: 597 AopUtils.invokeJoinpointUsingReflection(Object, Method, Object[]) line: 307 JdkDynamicAopProxy.invoke(Object, Method, Object[]) line: 198 $Proxy100.getSiteTree(long) line: not available the calling setRootZone in Page makes Hibernate issue a hit to database. I don't want this. So my question is + Why query String hpql = "SELECT n FROM Node n "; issues un-expected trace logs like above. Why the query String hpql = "SELECT n.nodename FROM Node n " not? What is the mechanism behind? Note: Im using hibernate caching level 2. In case I don't want to see that trace logs. I mean I just get Node data only. How to do ? Thanks for your help. Sorry for my bad english :( Van

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  • javaEE javax.xml.bind.MarshalException

    - by sandeep
    Hi, I am getting javax.xml.bind.MarshalException error. I am sending List from my webservice to the backingbean and I have this error. Here is my code: Errors WARNING: invocation error on ejb endpoint Login_webservice at /Login_webserviceService/Login_webservice : javax.xml.bind.MarshalException - with linked exception: [javax.xml.bind.JAXBException: class JPA.Cantable nor any of its super class is known to this context.] javax.xml.ws.WebServiceException: javax.xml.bind.MarshalException - with linked exception: [javax.xml.bind.JAXBException: class JPA.Cantable nor any of its super class is known to this context.] at com.sun.xml.ws.message.jaxb.JAXBMessage.writePayloadTo(JAXBMessage.java:325) at com.sun.xml.ws.message.AbstractMessageImpl.writeTo(AbstractMessageImpl.java:142) at com.sun.xml.ws.encoding.StreamSOAPCodec.encode(StreamSOAPCodec.java:109) at com.sun.xml.ws.encoding.SOAPBindingCodec.encode(SOAPBindingCodec.java:278) at com.sun.xml.ws.transport.http.HttpAdapter.encodePacket(HttpAdapter.java:380) at com.sun.xml.ws.transport.http.HttpAdapter.access$100(HttpAdapter.java:92) at com.sun.xml.ws.transport.http.HttpAdapter$HttpToolkit.handle(HttpAdapter.java:525) at com.sun.xml.ws.transport.http.HttpAdapter.handle(HttpAdapter.java:285) at com.sun.xml.ws.transport.http.servlet.ServletAdapter.handle(ServletAdapter.java:143) at org.glassfish.webservices.Ejb3MessageDispatcher.handlePost(Ejb3MessageDispatcher.java:116) at org.glassfish.webservices.Ejb3MessageDispatcher.invoke(Ejb3MessageDispatcher.java:87) at org.glassfish.webservices.EjbWebServiceServlet.dispatchToEjbEndpoint(EjbWebServiceServlet.java:196) at org.glassfish.webservices.EjbWebServiceServlet.service(EjbWebServiceServlet.java:127) at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) Backing bean @WebServiceRef(wsdlLocation = "http://localhost:26565/Login_webserviceService/Login_webservice?WSDL") public String login() { System.out.println("Login Phase entered"); int result = 0; List list; List finalList = null; try { Weblogin.LoginWebserviceService service = new Weblogin.LoginWebserviceService(); Weblogin.LoginWebservice port = service.getLoginWebservicePort(); result = port.login(voterID, password); Weblogin.LoginWebservice port1 = service.getLoginWebservicePort(); list = port1.candDetails(1); finalList = list; this.setList(finalList); } catch (Exception e) { e.printStackTrace(); } if (result == 1) return "polling"; else return "login"; } Webservice public List candDetails(int pollEvent) { List resultList = null; List finalList = null; try { if (pollEvent == 1) { resultList = em.createNamedQuery("Cantable.findAll").getResultList(); finalList = resultList; } } catch (Exception e) { e.printStackTrace(); } return resultList; }

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  • Running Network Application on port Server side give me error how can i solve it?

    - by Phsika
    if i run Server App. Exception occurs: on Dinle.Start() System.Net.SocketException - Only one usage of each socket address (protocol/network address/port) is normally permitted How can i solve this error? Server.cs using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.IO; using System.Net; using System.Net.Sockets; using System.Threading; namespace Server { public partial class Server : Form { Thread kanal; public Server() { InitializeComponent(); try { kanal = new Thread(new ThreadStart(Dinle)); kanal.Start(); kanal.Priority = ThreadPriority.Normal; this.Text = "Kanla Çalisti"; } catch (Exception ex) { this.Text = "kanal çalismadi"; MessageBox.Show("hata:" + ex.ToString()); kanal.Abort(); throw; } } private void Server_Load(object sender, EventArgs e) { Dinle(); } private void btn_Listen_Click(object sender, EventArgs e) { Dinle(); } void Dinle() { // IPAddress localAddr = IPAddress.Parse("localhost"); // TcpListener server = new TcpListener(port); // server = new TcpListener(localAddr, port); //TcpListener Dinle = new TcpListener(localAddr,51124); TcpListener Dinle = new TcpListener(51124); try { while (true) { Dinle.Start(); Exception is occured. Socket Baglanti = Dinle.AcceptSocket(); if (!Baglanti.Connected) { MessageBox.Show("Baglanti Yok"); } else { TcpClient tcpClient = Dinle.AcceptTcpClient(); if (tcpClient.ReceiveBufferSize 0) { byte[] Dizi = new byte[250000]; Baglanti.Receive(Dizi, Dizi.Length, 0); string Yol; saveFileDialog1.Title = "Dosyayi kaydet"; saveFileDialog1.ShowDialog(); Yol = saveFileDialog1.FileName; FileStream Dosya = new FileStream(Yol, FileMode.Create); Dosya.Write(Dizi, 0, Dizi.Length - 20); Dosya.Close(); listBox1.Items.Add("dosya indirildi"); listBox1.Items.Add("Dosya Boyutu=" + Dizi.Length.ToString()); listBox1.Items.Add("Indirilme Tarihi=" + DateTime.Now); listBox1.Items.Add("--------------------------------"); } } } } catch (Exception ex) { MessageBox.Show("hata:" + ex.ToString()); } } } }

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  • C++ vs. C++/CLI: Const qualification of virtual function parameters

    - by James McNellis
    [All of the following was tested using Visual Studio 2008 SP1] In C++, const qualification of parameter types does not affect the type of a function (8.3.5/3: "Any cv-qualifier modifying a parameter type is deleted") So, for example, in the following class hierarchy, Derived::Foo overrides Base::Foo: struct Base { virtual void Foo(const int i) { } }; struct Derived : Base { virtual void Foo(int i) { } }; Consider a similar hierarchy in C++/CLI: ref class Base abstract { public: virtual void Foo(const int) = 0; }; ref class Derived : public Base { public: virtual void Foo(int i) override { } }; If I then create an instance of Derived: int main(array<System::String ^> ^args) { Derived^ d = gcnew Derived; } it compiles without errors or warnings. When I run it, it throws the following exception and then terminates: An unhandled exception of type 'System.TypeLoadException' occurred in ClrVirtualTest.exe Additional information: Method 'Foo' in type 'Derived'...does not have an implementation. That exception seems to indicate that the const qualification of the parameter does affect the type of the function in C++/CLI (or, at least it affects overriding in some way). However, if I comment out the line containing the definition of Derived::Foo, the compiler reports the following error (on the line in main where the instance of Derived is instantiated): error C2259: 'Derived': cannot instantiate abstract class If I add the const qualifier to the parameter of Derived::Foo or remove the const qualifier from the parameter of Base::Foo, it compiles and runs with no errors. I would think that if the const qualification of the parameter affects the type of the function, I should get this error if the const qualification of the parameter in the derived class virtual function does not match the const qualification of the parameter in the base class virtual function. If I change the type of Derived::Foo's parameter from an int to a double, I get the following warning (in addition to the aforementioned error, C2259): warning C4490: 'override': incorrect use of override specifier; 'Derived::Foo' does not match a base ref class method So, my question is, effectively, does the const qualification of function parameters affect the type of the function in C++/CLI? If so, why does this compile and why are there no errors or warnings? If not, why is an exception thrown?

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  • ConfigurationErrorsException when running multiple instances due to file locking

    - by dr. evil
    I'm using My.Settings in my VB.NET application and when we run multiple instances rarely it's giving a ConfigurationErrorsException because the settings file locked by another instance. Is there anyway to fix this? This is happening during the OnShutdown process, also I'm not quite sure how can I catch that exception and handle it. Only thing I can think of is disabling onshutdown save and manually save it during the shutdown with extra retry + locking + exception handling.

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  • Hibernate Communications Link Failure in Hibernate Based Java Servlet application powered by MySQL

    - by Vatsala
    Let me describe my question - I have a Java application - Hibernate as the DB interfacing layer over MySQL. I get the communications link failure error in my application. The occurence of this error is a very specific case. I get this error , When I leave mysql server unattended for more than approximately 6 hours (i.e. when there are no queries issued to MySQL for more than approximately 6 hours). I am pasting a top 'exception' level description below, and adding a pastebin link for a detailed stacktrace description. javax.persistence.PersistenceException: org.hibernate.exception.JDBCConnectionException: Cannot open connection - Caused by: org.hibernate.exception.JDBCConnectionException: Cannot open connection - Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure - The last packet successfully received from the server was 1,274,868,181,212 milliseconds ago. The last packet sent successfully to the server was 0 milliseconds ago. - Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure - The last packet successfully received from the server was 1,274,868,181,212 milliseconds ago. The last packet sent successfully to the server was 0 milliseconds ago. - Caused by: java.net.ConnectException: Connection refused: connect the link to the pastebin for further investigation - http://pastebin.com/4KujAmgD What I understand from these exception statements is that MySQL is refusing to take in any connections after a period of idle/nil activity. I have been reading up a bit about this via google search, and came to know that one of the possible ways to overcome this is to set values for c3p0 properties as c3p0 comes bundled with Hibernate. Specifically, I read from here http://www.mchange.com/projects/c3p0/index.html that setting two properties idleConnectionTestPeriod and preferredTestQuery will solve this for me. But these values dont seem to have had an effect. Is this the correct approach to fixing this? If not, what is the right way to get over this? The following are related Communications Link Failure questions at stackoverflow.com, but I've not found a satisfactory answer in their answers. http://stackoverflow.com/questions/2121829/java-db-communications-link-failure http://stackoverflow.com/questions/298988/how-to-handle-communication-link-failure Note 1 - i dont get this error when I am using my application continuosly. Note 2 - I use JPA with Hibernate and hence my hibernate.dialect,etc hibernate properties reside within the persistence.xml in the META-INF folder (does that prevent the c3p0 properties from working?) edit - Here are the c3p0 parameters I tried out - select 1; 2

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  • Get HTTP Get parameters from Restlet Request

    - by Holograham
    I am trying to figure out how to get the parameters from a Restlet request object. my request comes in as /customer?userId=1 and I want to grab the parameter to pass to my DAO for the query. @Get("xml") public Representation toXml() throws ResourceException, Exception { try { //get param from request //call DAO with parameter } catch(Exception e) { throw e; } }

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  • Response is not available in this context when creation cookie's

    - by Sadegh
    hi i defined one class to create cookie by received parameter's from user. when i want to add cookie to context i receive an exception. My Class public static class ManageCookies { public static void Create(string name, string value) { HttpCookie cookie = new HttpCookie(name); cookie.Value = value; cookie.Expires = DateTime.Now.AddYears(1); HttpContext.Current.Response.Cookies.Add(cookie); } } Occured Exception: Response is not available in this context.

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  • Deleteing an image in run time

    - by Nadav Stern
    hey, i am trying to delete an image with the method: (the file path is correct by 100%) if(File.Exists(filePath)) File.Delete(filePath); and i am getting the following exception : An unhandled exception of type 'System.IO.IOException' occurred in mscorlib.dll Additional information: The process cannot access the file 'C:\visual_programming\yad2\yad2\bin\Debug\images\1.jpg' because it is being used by another process. thanks in advance for your help

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  • Using IoC and Dependency Injection, how do I wrap an existing implementation with a new layer of imp

    - by Dividnedium
    I'm trying to figure out how this would be done in practice, so as not to violate the Open Closed principle. Say I have a class called HttpFileDownloader that has one function that takes a url and downloads a file returning the html as a string. This class implements an IFileDownloader interface which just has the one function. So all over my code I have references to the IFileDownloader interface and I have my IoC container returning an instance of HttpFileDownloader whenever an IFileDownloader is Resolved. Then after some use, it becomes clear that occasionally the server is too busy at the time and an exception is thrown. I decide that to get around this, I'm going to auto-retry 3 times if I get an exception, and wait 5 seconds in between each retry. So I create HttpFileDownloaderRetrier which has one function that uses HttpFileDownloader in a for loop with max 3 loops, and a 5 second wait between each loop. So that I can test the "retry" and "wait" abilities of the HttpFileDownloadRetrier I have the HttpFileDownloader dependency injected by having the HttpFileDownloaderRetrier constructor take an IFileDownloader. So now I want all Resolving of IFileDownloader to return the HttpFileDownloaderRetrier. But if I do that, then HttpFileDownloadRetrier's IFileDownloader dependency will get an instance of itself and not of HttpFileDownloader. So I can see that I could create a new interface for HttpFileDownloader called IFileDownloaderNoRetry, and change HttpFileDownloader to implement that. But that means I'm changing HttpFileDownloader, which violates Open Closed. Or I could implement a new interface for HttpFileDownloaderRetrier called IFileDownloaderRetrier, and then change all my other code to refer to that instead of IFileDownloader. But again, I'm now violating Open Closed in all my other code. So what am I missing here? How do I wrap an existing implementation (downloading) with a new layer of implementation (retrying and waiting) without changing existing code? Here's some code if it helps: public interface IFileDownloader { string Download(string url); } public class HttpFileDownloader : IFileDownloader { public string Download(string url) { //Cut for brevity - downloads file here returns as string return html; } } public class HttpFileDownloaderRetrier : IFileDownloader { IFileDownloader fileDownloader; public HttpFileDownloaderRetrier(IFileDownloader fileDownloader) { this.fileDownloader = fileDownloader; } public string Download(string url) { Exception lastException = null; //try 3 shots of pulling a bad URL. And wait 5 seconds after each failed attempt. for (int i = 0; i < 3; i++) { try { fileDownloader.Download(url); } catch (Exception ex) { lastException = ex; } Utilities.WaitForXSeconds(5); } throw lastException; } }

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