Search Results

Search found 9610 results on 385 pages for 'common mistakes'.

Page 103/385 | < Previous Page | 99 100 101 102 103 104 105 106 107 108 109 110  | Next Page >

  • Accessing Virtual Host from outside LAN

    - by Ray
    I'm setting up a web development platform that makes things as easy as possible to write and test all code on my local machine, and sync this with my web server. I setup several virtual hosts so that I can access my projects by typing in "project" instead of "localhost/project" as the URL. I also want to set this up so that I can access my projects from any network. I signed up for a DYNDNS URL that points to my computer's IP address. This worked great from anywhere before I setup the virtual hosts. Now when I try to access my projects by typing in my DYNDNS URL, I get the 403 Forbidden Error message, "You don't have permission to access / on this server." To setup my virtual hosts, I edited two files - hosts in the system32/drivers/etc folder, and httpd-vhosts.conf in the Apache folder of my WAMP installation. In the hosts file, I simply added the server name to associate with 127.0.0.1. I added the following to the http-vhosts.conf file: <VirtualHost *:80> ServerAdmin webmaster@localhost DocumentRoot "c:/wamp/www/ladybug" ServerName ladybug ErrorLog "logs/your_own-error.log" CustomLog "logs/your_own-access.log" common </VirtualHost> <VirtualHost *:80> ServerAdmin webmaster@localhost DocumentRoot "c:/wamp/www" ServerName localhost ErrorLog "logs/localhost-error.log" CustomLog "logs/localhost-access.log" common </VirtualHost> Any idea why I can't access my projects from typing in my DYNDNS URL? Also, is it possible to setup virtual hosts so that when I type in http://projects from a random computer outside of my network, I access url.dyndns.info/projects (a.k.a. my WAMP projects on my home computer)? Help is much appreciated, thanks!

    Read the article

  • Hibernate ManyToMany and superclass mapping problem

    - by Jesus Benito
    Hi all, I need to create a relation in Hibernate, linking three tables: Survey, User and Group. The Survey can be visible to a User or to a Group, and a Group is form of several Users. My idea was to create a superclass for User and Group, and create a ManyToMany relationship between that superclass and Survey. My problem is that Group, is not map to a table, but to a view, so I can't split the fields of Group among several tables -which would happen if I created a common superclass-. I thought about creating a common interface, but mapping to them is not allowed. I will probably end up going for a two relations solution (Survey-User and Survey-Group), but I don't like too much that approach. I thought as well about creating a table that would look like: Survey Id | ElementId | Type ElementId would be the Group or UserId, and the type... the type of it. Does anyone know how to achieve it using hibernate annotations? Any other ideas? Thanks a lot

    Read the article

  • struts datagrid problem - can't solve this problem

    - by shien-angel
    i am creating datagrid using the struts-layout. and i encountered this problem javax.servlet.ServletException: DispatchMapping[/monitor/datagridBL]???????????????????? at org.apache.struts.actions.DispatchAction.getParameter(DispatchAction.java:325) at org.apache.struts.actions.DispatchAction.execute(DispatchAction.java:170) at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) at jp.terasoluna.fw.web.struts.action.RequestProcessorEx.process(RequestProcessorEx.java:149) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) at javax.servlet.http.HttpServlet.service(HttpServlet.java:707) at javax.servlet.http.HttpServlet.service(HttpServlet.java:820) at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:227) at weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:125) at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:292) at weblogic.servlet.internal.TailFilter.doFilter(TailFilter.java:26) at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56) at jp.co.anicom.fw.web.common.controller.RequestEncodeFilter.doFilter(RequestEncodeFilter.java:42) at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56) at jp.co.anicom.fw.web.common.controller.SessionExpirationFilter.doFilter(SessionExpirationFilter.java:89) at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56) at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3588) at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321) at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:121) at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2200) at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2106) at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1428) at weblogic.work.ExecuteThread.execute(ExecuteThread.java:201) at weblogic.work.ExecuteThread.run(ExecuteThread.java:173) i have been looking for ways on how to solve this. would somebody help me please...

    Read the article

  • Best way to store list of numbers and to retrieve them

    - by bingoNumbers
    Hi. What is the best way to store a list of random numbers (like lotto/bingo numbers) and retrieve them? I'd like to store on a Database a number of rows, where each row contains 5-10 numbers ranging from 0 to 90. I will store a big number of those rows. What I'd like to be able is to retrieve the rows that have at least X number in common to a newly generated row. Example: [3,4,33,67,85,99] [55,56,77,89,98,99] [3,4,23,47,85,91] Those are on the DB I will generate this: [1,2,11,45,47,88] and now I want to get the rows that have at least 1 number in common with this one. The easiest (and dumbest?) way is to make 6 select and check for similar results. I thought to store numbers with a large binary string like 000000000000000000000100000000010010110000000000000000000000000 with 99 numbers where each number represent a number from 1 to 99, so if I have 1 at the 44th position, it means that I have 44 on that row. This method is probably shifting the difficult tasks to the Db but it's again not very smart. Any suggestion?

    Read the article

  • How to record different authentication types (username / password vs token based) in audit log

    - by RM
    I have two types of users for my system, normal human users with a username / password, and delegation authorized accounts through OAuth (i.e. using a token identifier). The information that is stored for each is quite different, and are managed by different subsytems. They do however interact with the same tables / data within the system, so I need to maintain the audit trail regardless of whether human user, or token-based user modified the data. My solution at the moment is to have a table called something like AuditableIdentity, and then have the two types inheriting off that table (either in the single table, or as two seperate tables with 1 to 1 PK with AuditableIdentity. All operations would use the common AuditableIdentity PK for CreatedBy, ModifiedBy etc columns. There isn't any FK constraint on the audit columns, so any text can go in there, but I want an easy way to easily determine whether it was a human or system that made the change, and joining to the one AuditableIdentity table seems like a clean way to do that? Is there a best practice for this scenario? Is this an appropriate way of approaching the problem - or would you not bother with the common table and just rely on joins (to the two seperate un-related user / token tables) later to determine which user type matches which audit records?

    Read the article

  • Simple Enterprise Library console application refuses to compile

    - by Vadim
    I just downloaded and installed Microsoft Enterprise Library 5.0. I fired up VS 2010 to play with EL 5 and created a very simple console application. However, it would not compile. I got the following error: The type or namespace name 'Data' does not exist in the namespace 'Microsoft.Practices.EnterpriseLibrary' (are you missing an assembly reference?) I added Microsoft.Practices.EnterpriseLibrary.Common, Microsoft.Practices.EnterpriseLibrary.Data, and Microsoft.Practices.Unity references to my project. Here's the simple code that refuses to compile. using Microsoft.Practices.EnterpriseLibrary.Common.Configuration.Unity; using Microsoft.Practices.EnterpriseLibrary.Data; using Microsoft.Practices.Unity; namespace EntLib { class Program { static void Main(string[] args) { IUnityContainer container = new UnityContainer(); container.AddNewExtension<EnterpriseLibraryCoreExtension>(); var defaultDatabase = container.Resolve<Database>(); } } } The error above complains about line #2 : using Microsoft.Practices.EnterpriseLibrary.Data; Someone probably will point out to a stupid mistake by me, but at the moment I fail to see it. I tried to remove and add again Microsoft.Practices.EnterpriseLibrary.Data to refences but it didn't help.

    Read the article

  • restrict documents for mapreduce with mongoid

    - by theBernd
    I implemented the pearson product correlation via map / reduce / finalize. The missing part is to restrict the documents (representing users) to be processed via a filter query. For a simple query like mapreduce(mapper, reducer, :finalize => finalizer, :query => { :name => 'Bernd' }) I get this to work. But my filter criteria is a little bit more complicated: I have one set of preferences which need to have at least one common element and another set of preferences which may not have a common element. In a later step I also want to restrict this to documents (users) within a certain geographical distance. Currently I have this code working in my map function, but I would prefer to separate this into either query params as supported by mongoid or a javascript function. All my attempts to solve this failed since the code is either ignored or raises an error. I did a couple of tests. A regular find like User.where(:name.in => ['Arno', 'Bernd', 'Claudia']) works and returns #<Mongoid::Criteria:0x00000101f0ea40 @selector={:name=>{"$in"=>["Arno", "Bernd", "Claudia"]}}, @options={}, @klass=User, @documents=[]> Trying the same with mapreduce User.collection. mapreduce(mapper, reducer, :finalize => finalizer, :query => { :name.in => ['Arno', 'Bernd', 'Claudia'] }) fails with `serialize': keys must be strings or symbols (TypeError) in bson-1.1.5 The intermediate query parameter looks like this :query=>{#<Mongoid::Criterion::Complex:0x00000101a209e8 @key=:name, @operator="in">=>["Arno", "Bernd", "Claudia"]} and at least @operator looks a bit weird to me. I'm also uncertain if the class name can be omitted. BTW - I'm using mongodb 1.6.5-x86_64, and the mongoid 2.0.0.beta.20, mongo 1.1.5 and bson 1.1.5 gems on MacOS. What am I doing wrong? Thanks in advance.

    Read the article

  • Which articles I've should read before starting to make my custom drawn winforms app?

    - by Dmitriy Matveev
    Hello! I'm currently developing a windows forms application with a lot of user controls. Some of them are just custom drawn buttons or panels and some of them are a compositions of these buttons and panels inside of FlowLayoutPanels and TableLayoutPanels. And the window itself is also custom drawn. I don't have much experience in winforms development, but I've made a proper decomposition of proposed design into user controls and implementation is already almost finished. I've already solved many arisen problems during development by the help of the google, msdn, SO and several dirty hacks (when nothing were helping) and still experiencing some of them. There are a lot of gaps in my knowledge base, since I don't know answers to many questions like: When I should use things like double buffer, suspended layout, suspended redraw ? What should I do with the controls which shouldn't be visible at some moment ? Common performance pitfalls (I think I've fallen in in several ones) ? So I think there should be some great articles which can give some knowledge enough to avoid most common problems and improve performance and maintainability of my application. Maybe some of you can recommend a few?

    Read the article

  • CrystalDecisions.Web reference version changes suddenly when run the webapp

    - by Somebody
    I'm breaking my head with this issue, I have a webapp that has a report using crystal report, in the development pc it works fine, but when copy the same project to another pc, when I load the project (VS 2003) the following msg appears: One or more projects in solution need to be updated to use Crystal Reports XI Release 2. If you choose "Yes", the update will be applied permanently... I choose "Yes" and after that I can see that CrystalDecisions.Web reference has the correct version, and location according to the develpment machine, in this case: 11.5.3300.0. But when run the webapp, I can see when the version and path suddenly changes to: 11.0.3300.0. And when trying to see the report the following error appears: Parser Error Message: The base class includes the field 'CrystalReportViewer1', but its type (CrystalDecisions.Web.CrystalReportViewer) is not compatible with the type of control (CrystalDecisions.Web.CrystalReportViewer). the asp.net has the following: <%@ Register TagPrefix="cr" Namespace="CrystalDecisions.Web" Assembly="CrystalDecisions.Web, Version=11.5.3300.0, Culture=neutral, PublicKeyToken=692fbea5521e1304" %> How is this possible? what's happening here? EDIT This is what I did: the wrong version (11.0.3300.0) was located at: C:\Program Files\Common Files\Business Objects\3.0\managed and the right version (11.5.3300.0) is located at: C:\Program Files\Business Objects\Common\3.5\managed So I just deleted the files of the wrong solution, and I made it work in my new computer, no more errors when running the webapp, the report shows fine. But when try to do the same thing in production server, a different error came out, now an exception: This report could not be loaded due to the following issue: The type initializer for 'CrystalDecisions.CristalReports.Engine.ReportDocument' threw an exception. Any idea what could be causing this error now? Here is the code: Try Dim cr As New ReportDocument cr.Load(strpath) cr.SetDatabaseLogon("usring", "pwding") Select Case rt Case 1 cr.SummaryInfo.ReportTitle = "RMA Ticket" Case 2 cr.SummaryInfo.ReportTitle = "Service Ticket" End Select 'cr.SummaryInfo.ReportTitle = tt cr.SetParameterValue("TicketNo", tn) 'cr.SummaryInfo.ReportComments = comment CrystalReportViewer1.PrintMode = CrystalDecisions.Web.PrintMode.ActiveX CrystalReportViewer1.ReportSource = cr CrystalReportViewer1.ShowFirstPage() 'cr.Close() 'cr.Dispose() Catch ex As Exception MsgBox1.alert("This report could not be loaded due to the following issue: " & ex.Message) End Try

    Read the article

  • Where can I find a professional image gallery built on a javascript framework?

    - by user278457
    I'm looking to find a galleria replacement, hopefully using jQuery but other javascript frameworks such as prototype or mootools are fine too. I used galleria a while back, and I need a similar product now. Unfortunately, the devkick.com domain seems to have disappeared in the meantime and I'm wary of using products that aren't actively maintained. I'm willing to pay up to $50 per site for licensing costs, if the product meets my needs. I'm specifically looking for a gallery with the following features: Every image in the gallery preloads asap, not as the user clicks "next" Minimalist default css to keep my subsequent styling headaches down, preferably a "darkroom" style by default, much as galleria looks Each element that constructs the image gallery should be simple and logical to reference with CSS As easy to install as adding a css class to a single unordered list No dependencies other than the core jQuery/other library, including "easing" and other effects must be optional Works on browsers back to IE6, Firefox 3, Safari (and iPhone), Chrome, Opera Has a javascript API that lets me trigger callback functions on common events such as "user clicks next" or "image loads" degrades gracefully without javascript, either displays images as a list, or just displays the first image in the list bonus: The gallery can display other content, such as video or external sites, like the modal boxes at shadowbox-js.com well documented minimal bandwidth requirement - .js file should be ~10kb minified bonus: The gallery source is hosted on a reliable CDN like google's bonus: Thumbnails for images do not appear until the main image has loaded bonus: includes ability to set parameters with JSON to change common behaviours, such as slide/fade transitions or automatic image switch every X seconds

    Read the article

  • Can you recommend a full-text search engine?

    - by Jen
    Can you recommend a full-text search engine? (Preferably open source) I have a database of many (though relatively short) HTML documents. I want users to be able to search this database by entering one or more search words in my C++ desktop application. Hence, I’m looking for a fast full-text search solution to integrate with my app. Ideally, it should: Skip common words, such as the, of, and, etc. Support stemming, i.e. search for run also finds documents containing runner, running and ran. Be able to update its index in the background as new documents are added to the database. Be able to provide search word suggestions (like Google Suggest) Have a well-documented API To illustrate, assume the database has just two documents: Document 1: This is a test of text search. Document 2: Testing is fun. The following words should be in the index: fun, search, test, testing, text. If the user types t in the search box, I want the application to be able to suggest test, testing and text (Ideally, the application should be able to query the search engine for the 10 most common search words starting with t). A search for testing should return both documents. Other points: I don't need multi-user support I don't need support for complex queries The database resides on the user's computer, so the indexing should be performed locally. Can you suggest a C or C++ based solution? (I’ve briefly reviewed CLucene and Xapian, but I’m not sure if either will address my needs, especially querying the search word indexes for the suggest feature).

    Read the article

  • Developing cross platform mobile application

    - by sohilv
    More and more mobile platforms are being launched and sdk's are available to developers. There are various mobile platform are available, Android,iOS,Moblin,Windows mobile 7,RIM,symbian,bada,maemo etc. And making of corss platform application is headache for developers. I am searching common thing across the platforms which will help to developers who want to port application to all platforms.Like what is the diff screen resolution, input methods, open gl support etc. please share details that you know for the any of platform . or is there possibilities , by writing code in html (widget type of thing) and load it into native application. I know about the android , in which we can add the web view into application. by calling setContentView(view) Please share the class details where we can add the html view into native application of different type of platforms that you know. Purpose of this thread is share common details across developers. marking as community wiki. Cross platform tools & library XMLVM and iSpectrum (cross compile Java code from an Android app or creating one from scratch Phone Gap (cross platform mobile apps) Titanium (to build native mobile and desktop apps with web technologies) Mono Touch ( C# for iphone ) rhomobile - http://rhomobile.com/ samples are here: http://github.com/rhomobile/rhodes-system-api-samples Sencha Touch - Sencha Touch is a HTML5 mobile app framework that allows you to develop web apps that look and feel native on Apple iOS and Google Android touchscreen devices. http://www.sencha.com/products/touch/ Corona - Iphone/Ipad / Android application cross platform library . Too awesome. http://anscamobile.com/corona/ A guide to port existing Android app to Windows Phone 7 http://windowsphone.interoperabilitybridges.com/articles/windows-phone-7-guide-for-iphone-application-developers

    Read the article

  • accepts_nested_attributes with Model.update for multiple models

    - by Ohad
    Hi, I'm trying to follow http://railscasts.com/episodes/198-edit-multiple-individually but I would like to save objects which are nested (accepts_nested_attributes_for). I've added the following in my controller: def edit_multiple @people = Person.find(params[:person_ids], :include => [:parameters]) end def update_multiple keys = params[:people].keys if keys.empty? flash[:error] = "Please select at least one person" redirect_to :back and return end values = keys.map {|k| params[:people][k]} @people = Person.update(keys,values).reject { |h| h.errors.empty? } if @people.empty? flash[:notice] = 'Updated people!' redirect_to person_path else redirect_to edit_multiple_path end end and in the view: <% form_tag update_multiple_people_path, :method => :post do %> <% for person in @people %> <% fields_for "people[]", host do |f| %> <%= f.error_messages :object_name => "person" %> <h3><%= h person.name %></h3> <% for parameter in person.parameters %> <% f.fields_for "person_parameters[]", parameter do |builder| -%> <%= render "common/parameters", :f => builder %> <% end -%> <% end -%> <p><%= link_to_add_fields "Add a parameter", f, :person_parameters, "common/parameters" %></p> <% end %> <% end %> <p><%= submit_tag "Edit these Parameter(s)" %></p> <% end %> but I'm always getting a mistmatch - e.g. ActiveRecord::AssociationTypeMismatch and Parameter(#70341811965140) expected, got Array(#70341874300460) Thanks!

    Read the article

  • Java Client .class File Protection

    - by Zac
    I am in the requirements phase of building a JEE application that will most likely run on a GlassFish/JBoss backend (doesn't matter for now). I know I shouldn't be thinking about architecture at requirements time, but one can't help but start to imagine how the components would all snap together :-) Here are some hard, non-flexible requirements on the client-side: (1) The client application will be a Swing box (2) The client is free to download, but will use a subscription model (thus requiring a login mechanism with server-side authentication/authorization, etc.) (3) Yes, Java is the best platform solution for the problem at hand for reasons outside the scope of this post (4) The client-side .class files need safeguarding against decompiling That last (4th) requirement is the basis of this post. I'm not really worried about someone actually decompiling and getting at my source code: in the end, it's just Swing controls driven by some lightweight business logic. I'm worried about a scenario where someone decompiles my code, modifies it to exploit/attack the server, re-compiles, and fires it up. I've envisioned all sorts of nasty solutions, but didn't know if this was a common problem with a common solution for JEE developers. Any thoughts? Not interested in "code obfuscation" techniques! Thanks for any input!

    Read the article

  • How to include external classes in a GAE deployment?

    - by kodra
    I am using the Google plug-in for Eclipse and have the following problem: The project consists of a GWT based GUI talking to a server running on GAE and using JPA. Additionally there is a project to migrate the legacy data to the new datastore. Since these both project use common data model, I have extracted a set of interfaces and enums into a separate project and set the other two projects dependencies on it. The Java App project seems to work, but the GWT/GAE only works if I manually copy the classes into the WEB-INF/classes directory. Obviously this is only working when using the housted mode. Anybody knows how to configure such a multi project setup in Eclipse? Also, I am not sure if the multi project layout is the best solution. The set of common model objects is used in all 3 areas: user client (GWT project compiling standard folders client and shared) server side (providing services for GWT-RPC, uploading and different feeds) migration application (posting the legacy data to the upload servlet) What are the architectural options to keep the amount of duplicated classes on minimum?

    Read the article

  • Programming Concepts: What should be done when an exception is thrown?

    - by Dooms101
    This does not really apply to any language specifically, but if it matters I am using VB.NET in Visual Studio 2008. I can't seem to find anything really that useful using Google about this topic, but I was wondering what is common practice when an exception is thrown and caught but since it has been thrown the application cannot continue operating. For example I have exceptions that are thrown by my FileLoader class when a file cannot be found or when a file is deemed corrupt. The exception is only thrown within the class and is not handled really. If the error is detected, then the exception is thrown and whatever function is was thrown is basically quits. So in the code trying to create that object or call one of its members I use a Try...Catch statement. However, I was wondering, what should even do when this exception is caught? My application needs these files to be intact, and if they are not, the application is almost useless. So far I just pop up a message box telling the user their is an error and to reinstall. What else can I do, or better, what's common practice in these situations?

    Read the article

  • MySQL query pulling from two tables, display in correct fields

    - by Matt Nathanson
    I'm trying to select all fields in two separate tables as long as they're sharing a common ID. //mysql query $result = mysql_query("SELECT * FROM project, links WHERE project.id = links.id and project.id = $clientID") //displaying the link if ($row['url'] != null){ echo "<div class='clientsection' id='links'>Links</div>"; echo "<a class='clientlink' id='link1' href='" . $row['url'] . "'>" . $row['name'] . "</a>"; } else { echo "<a class='clientlink' id='link1' href='" . $row['url'] . "' style='display:none;'>" . $row['name'] . "</a>"; }; As you can see, my tables are "projects", and "links" Each is sharing a common field "id" for reference. It looks as though where both links.id and project.id are equal, it outputs anything, but when there is no links.id associated with a given $clientID the container relative to the $clientID doesn't display at all. Essentially I'm using this to add links dynamically to a specific client in this CMS and if there are no links, I want the container to show up anyway. Hopefully I've expressed myself clearly, any pointers in the right direction are appreciated. Thanks!

    Read the article

  • How to make active services highly available?

    - by Jader Dias
    I know that with Network Load Balancing and Failover Clusteringwe can make passive services highly available. But what about active apps? Example: One of my apps retrieves some content from a external resource in a fixed interval. I have imagined the following scenarios: Run it in a single machine. Problem: if this instance falls, the content won't be retrieved Run it in each machine of the cluster. Problem: the content will be retrieved multiple times Have it in each machine of the cluster, but run it only in one of them. Each instance will have to check some sort of common resource to decide whether it its turn to do the task or not. When I was thinking about the solution #3 I have wondered what should be the common resource. I have thought of creating a table in the database, where we could use it to get a global lock. Is this the best solution? How does people usually do this? By the way it's a C# .NET WCF app running on Windows Server 2008

    Read the article

  • How to use Data aware controls "correctly"?

    - by lyborko
    Hi, I would like to ask experienced users, if you prefer to use data aware controls to add, insert, delete and edit data in DB or you favor to do it manualy. I developed some DB applications, in which for the sake of "user friendly policy" I run into complicated web of table events (afterinsert, afteredit, after... and beforeedit, beforeinsert, before...). After that it was a quite nasty work to debug the application. Aware of this risk (later by another application) I tried to avoid this problem, so I paid increased attention to write code well, readable and comprehensive. It seemed everything all right from the beginning, but as I needed to handle some preprocessing stuff before sending and loading data etc, I run into the same problems again, "slowly and inevitably". Sometime I could not use dataaware controls anyway, and what seemed to be a "cool" feature of DAControl at the beginning it turned to an obstacle on the end. I "had to" write special routine for non-dataaware controls, in order to behave as dataaware. Then I asked myself, why on earth should I use dataaware controls? Is it better to found application architecture on non-dataaware controls? It requires more time to write bug-proof code, of course, but does it worth of it? I do not know... I happened to me several times, like jinxed : paradise on the beginning hell on the end... I do not know, if I use wrong method to write DB program, if there is some standard common practice how to proceed. Or if it is common problem to everybody? Thanx for advices and your experiences

    Read the article

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

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

    Read the article

  • Is this a safe/valid hash method implementation?

    - by Sean
    I have a set of classes to represent some objects loaded from a database. There are a couple variations of these objects, so I have a common base class and two subclasses to represent the differences. One of the key fields they have in common is an id field. Unfortunately, the id of an object is not unique across all variations, but within a single variation. What I mean is, a single object of type A could have an id between, say, 0 and 1,000,000. An object of type B could have an id between, 25,000 and 1,025,000. This means there's some overlap of id numbers. The objects are just variations of the same kind of thing, though, so I want to think of them as such in my code. (They were assigned ids from different sets for legacy reasons.) So I have classes like this: @class BaseClass @class TypeAClass : BaseClass @class TypeBClass : BaseClass BaseClass has a method (NSNumber *)objectId. However instances of TypeA and TypeB could have overlapping ids as discussed above, so when it comes to equality and putting these into sets, I cannot just use the id alone to check it. The unique key of these instances is, essentially, (class + objectId). So I figured that I could do this by making the following hash function on the BaseClass: -(NSUInteger)hash { return (NSUInteger)[self class] ^ [self.objectId hash]; } I also implemented isEqual like so: - (BOOL)isEqual:(id)object { return (self == object) || ([object class] == [self class] && [self.objectId isEqual:[object objectId]]); } This seems to be working, but I guess I'm just asking here to make sure I'm not overlooking something - especially with the generation of the hash by using the class pointer in that way. Is this safe or is there a better way to do this?

    Read the article

  • Parsing XML in C# from stream

    - by Phillip
    I've tried several methods, from Linq to loading the data to an XML document, but i can't seem to be able to return the result that i need. here's the example XML: <serv:message xmlns:serv="http://www.webex.com/schemas/2002/06/service" xmlns:com="http://www.webex.com/schemas/2002/06/common" xmlns:event="http://www.webex.com/schemas/2002/06/service/event"><serv:header><serv:response><serv:result>SUCCESS</serv:result><serv:gsbStatus>PRIMARY</serv:gsbStatus></serv:response></serv:header><serv:body><serv:bodyContent xsi:type="event:createEventResponse" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><event:sessionKey>11111111</event:sessionKey><event:guestToken>111111111111111111111</event:guestToken></serv:bodyContent></serv:body></serv:message> And, here's what i've tried to do: StreamReader reader = new StreamReader(dataStream); XmlDocument doc = new XmlDocument(); doc.LoadXml(reader.ReadToEnd()); XmlNamespaceManager ns = new XmlNamespaceManager(doc.NameTable); XmlNamespaceManager ns2 = new XmlNamespaceManager(doc.NameTable); XmlNamespaceManager ns3 = new XmlNamespaceManager(doc.NameTable); ns.AddNamespace("serv", "http://www.webex.com/schemas/2002/06/service"); ns2.AddNamespace("com", "http://www.webex.com/schemas/2002/06/common"); ns3.AddNamespace("event", "http://www.webex.com/schemas/2002/06/service/event"); XmlNode node = doc.SelectSingleNode("result",ns); Yet, for some reason i cannot ever seem to return the actual result, which should be either 'SUCCESS' or 'FAILURE' based on the actual xml above. How can i do this?

    Read the article

  • Problem with Active Record

    - by kshchepelin
    Hello everyone. Lets assume we have a User model. And user can plan some activities. The number of types of activities is about 50. All activities have common properties, such as start_time, end_time, user_id, etc. But each of them has some unique properties. Now we have each activity living in its own table in DB. And thats why we have such terrible sql queries like SELECT * FROM `first_activities_table` WHERE (`first_activity`.`id` IN (17,18)) SELECT * FROM `second_activities_table` WHERE (`second_activity`.`id` = 17) ..... SELECT * FROM `n_activities_table` WHERE (`n_activity`.`id` = 44) About 50 queries. That's terrible. There are different ways to solve this. Choose the activity type with the biggest number of properties, create the table 'Activities' and have STI model. But this way we must name our columns in uncomfortable way and often the record in that table would have some NULL fields. Also STI model, but having columns, common for all of activity types and some blob column with serialized properties. But we have to do some search on activities - there can be a problem. And serialization is quite slow. Please help me dealing with this. Maybe my problem has quite different solution that will fit my needs. Thanks for help.

    Read the article

  • A commercial software but open and free for personal/edu. How to license?

    - by Ivan
    I am developing a software to sell for business use but am willing to make it free and open-source for personal and educational use. Actually I can see the flowing requirements I would like the license to set: Personal and educational usage of the program and its source codes is to be free. In case of publishing of derivative works the original work and author (me) must be mentioned (incl. textual link to my website in a not-very-far-hidden place) and the derivative work must have different name. A derivative work can be closed-source. In every case of commercial (when the end-user is a commercial body (as a company (expect of non-profit organizations), an individual entrepreneur or government office)) usage of my work or any of derivative works made by anyone, the end-user, service provider or the derivative author must buy a commercial license from me. I mean no guarantees or responsibilities, whether expressed or implied... (except the case when one explicitly purchases a support service contract from me and the particular contract specifies a responsibility). Is there a known common license for this case? As far as I can see now it can not be OSI-approved as it does not comply to the §6. of OSI definition of open source. But there still can be an a common known reusable license for this case as it looks quite natural, I think.

    Read the article

  • One big executable or many small DLL's?

    - by Patrick
    Over the years my application has grown from 1MB to 25MB and I expect it to grow further to 40, 50 MB. I don't use DLL's, but put everything in this one big executable. Having one big executable has certain advantages: Installing my application at the customer is really: copy and run. Upgrades can be easily zipped and sent to the customer There is no risk of having conflicting DLL's (where the customer has version X of the EXE, but version Y of the DLL) The big disadvantage of the big EXE is that linking times seem to grow exponentially. Additional problem is that a part of the code (let's say about 40%) is shared with another application. Again, the advantages are that: There is no risk on having a mix of incorrect DLL versions Every developer can make changes on the common code which speeds up developments. But again, this has a serious impact on compilation times (everyone compiles the common code again on his PC) and on linking times. The question http://stackoverflow.com/questions/2387908/grouping-dlls-for-use-in-executable mentions the possibility of mixing DLL's in one executable, but it looks like this still requires you to link all functions manually in your application (using LoadLibrary, GetProcAddress, ...). What is your opinion on executable sizes, the use of DLL's and the best 'balance' between easy deployment and easy/fast development?

    Read the article

< Previous Page | 99 100 101 102 103 104 105 106 107 108 109 110  | Next Page >