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  • How to Access a Button present inside a Custom Control, from the implementing page?

    - by Subhen
    Hi, I have my generic.xaml containing the following code: <ControlTemplate TargetType="local:customVideoControl"> <Grid> <Grid.RowDefinitions> <RowDefinition Height="600"/> <RowDefinition Height="200"/> </Grid.RowDefinitions> <Grid.ColumnDefinitions> <ColumnDefinition Width="200"/> <ColumnDefinition Width="200"/> <ColumnDefinition Width="200"/> </Grid.ColumnDefinitions> <MediaElement x:Name="customMediaPlayer" Source="{TemplateBinding CustomMediaSource}" HorizontalAlignment="Center" VerticalAlignment="Center" Height="{TemplateBinding Height}" Width="{TemplateBinding Width}" Grid.Row="0" Grid.ColumnSpan="3" /> <ToggleButton x:Name="playPauseBtn" Height="50" Width="50" Content="Pause" Grid.Row="1" Grid.Column="0"/> <Button x:Name="prevBtn" Height="50" Width="50" Content="Prev" Grid.Row="1" Grid.Column="1"/> <Button x:Name="nextBtn" Height="50" Width="50" Content="Next" Grid.Row="1" Grid.Column="2"/> </Grid> </ControlTemplate> Now on applyTemplate , I am accessing the controls like below: public override void OnApplyTemplate() { base.OnApplyTemplate(); ToggleButton playPauseBtn = GetTemplateChild("playPauseBtn") as ToggleButton; Button prevBtn= GetTemplateChild("prevBtn") as Button; Button nextBtn = GetTemplateChild("nextBtn") as Button; MediaElement customMediaPlayer = GetTemplateChild("customMediaPlayer") as MediaElement; playPauseBtn.Checked += (obj, Args) => { customMediaPlayer.Pause(); playPauseBtn.Content = "Play"; }; playPauseBtn.Unchecked += (obj, Args) => { customMediaPlayer.Play(); playPauseBtn.Content = "Pause"; }; nextBtn.Click += (obj, Args) => { customMediaPlayer.Source=new Uri(CustomMediaSource.ToString(),UriKind.RelativeOrAbsolute); }; prevBtn.Click += (obj, Args) => { customMediaPlayer.Source = new Uri(CustomMediaSource.ToString(), UriKind.RelativeOrAbsolute); }; } Now I want acccess the nextBtn, in the page where I am implementing like CustomVideoControl myVControl=new CustomVideoControl(); This will create the instance of the control, but I want to do something on the click of next and previous button, thta is present inside the CustomVideoControl in generic.xaml. Any help will be greatly appreciated. Thanks, Subhen

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  • how to associate a custom Page with new doccument in doccument library,also the fields in rhe page w

    - by Ankur Madaan
    Hey, I am onto a task in which i have to create a link in a doccument library either upload or new link,clicking on which a form/page "not infopath" will get open and allow to upload the doccument and along with that we have some text boxes on the same page which will be asking for the properties of the doccument(like "Customer of the doccument","content Developer") and after filling up all of the things when user click on submit than in the doccument library the value of the url as well as properties comes into the columns/fields of the doccument library. Can anyone have the solution for this?

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  • display result in status after it post

    - by nisardotnet
    my question is continuation of what i have posted here i want to know how to display a result status based on my return result from Web Method here is my post code: beforeSubmit: function(data) { var myData = { "firstName": escape($('#txtFirstName').val()), "lastName": escape($('#txtLastName').val()) }; $.ajax(<br> { type: "POST", url: "VisitorWS.asmx/AddVisitors", data: JSON.stringify(myData), contentType: "application/json; charset=utf-8", dataType: "json", success: function(data) { $("#status").fadeTo(500, 1, function() { $(this).html("You are now registered!").fadeTo(5000, 0); }) }, error: function(data) { $("#status").fadeTo(5000, 1, function() { $(this).html("Failed!").fadeTo(5000, 0); }) } }); WebMethod [WebMethod] public bool AddVisitors(string firstName, string lastName) { if (firstName == "test") { return true; } return false; } so based on true or false i want to display a message on the client side.

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  • How to use unlinked result of linq?

    - by user46503
    Hello, for example I'm trying to get the data from database like: using (ExplorerDataContext context = new ExplorerDataContext()) { ObjectQuery<Store> stores = context.Store; ObjectQuery<ProductPrice> productPrice = context.ProductPrice; ObjectQuery<Product> products = context.Product; res = from store in stores join pp in productPrice on store equals pp.Store join prod in products on pp.Product equals prod select store; } After this code I cannot transfer the result to some another method because the context doesn't exist more. How could I get the unlinked result independent on the context? Thanks

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  • Hyperlinks in VS2008 Test Result Details

    - by Red XIII
    In case when resulting string in "Test Result Details" (TRD) is very long, the Visual Studio 2008 crashes. I fixed this by sending the result data into a file. There is a problem, however, because there isn't a simple way to open such file. Of course, I can manually open folder and then the file, but it isn't very efficient. Now, to the questions part. Is there a possibility to include in the "Error Message" part of TRD a hyperlink to a file? (something similar to what we can already find in the stack trace part) If not, is there any way to add such functionality (easy opening of a file) to TRD? If not, are there any ways to expand the default reporting of VS? Thanks for any help.

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  • nested list comprehension using intermediate result

    - by KentH
    I am trying to grok the output of a function which doesn't have the courtesy of setting a result code. I can tell it failed by the "error:" string which is mixed into the stderr stream, often in the middle of a different conversion status message. I have the following list comprehension which works, but scans for the "error:" string twice. Since it is only rescanning the actual error lines, it works fine, but it annoys me I can't figure out how to use a single scan. Here's the working code: errors = [e[e.find('error:'):] for e in err.splitlines() if 'error:' in e] The obvious (and wrong) way to simplify is to save the "find" result errors = [e[i:] for i in e.find('error:') if i != -1 for e in err.splitlines()] However, I get "UnboundLocalError: local variable 'e' referenced before assignment". Blindly reversing the 'for's in the comprehension also fails. How is this done? THanks. Kent

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  • Combining IN and NOT IN in SQL as single result

    - by UltraVi01
    I apologize for the vague title. I am attempting to write a query that returns an alias column with matching values (resulting from an IN) as well as an alias column with values that do not match (using NOT IN). I want the result set to have: userId | matches | nonmatches. I currently have the following query which returns the matches as expected. I am having trouble getting the nonmatches in the result set -- that is, from a NOT IN statement SET @userId = 9; SELECT ug.user_id, COUNT(DISTINCT goal_id) as matches FROM user_goal ug WHERE ug.user_id!=@userId AND goal_id IN (SELECT iug.goal_id FROM user_goal iug WHERE user_id=@userId) GROUP BY user_id ORDER BY matches DESC LIMIT 4 So, the NOT IN would look something like this: goal_id NOT IN(SELECT uggg.goal_id FROM user_goal uggg WHERE user_id=@userId) AS nonmatches I am just not sure how to incorporate the NOT IN statement in my query so I get all the results

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  • Dynamically set the result of a TSQL query using CASE WHEN

    - by Name.IsNullOrEmpty
    SELECT MyTable.Name,(SELECT CASE WHEN ISNULL(SUM(TotalDays), 0) <= 0 THEN 0 ELSE SUM(TotalDays) END AS Total FROM Application AS Applications WHERE (ID = MyTable.id)) - MIN(Assignments) AS Excesses FROM MyTable The above TSQL statement is a subquery in a main query. When i run it, if TotalDays is NULL or <=0, then Total is set to 0 (zero). What i would like to do here is to set the result of the whole query(Excesses) to 0. I want (Excesses) which is the result of Total - Min(Assignments) to be set to 0 if its NULL or <=0. I want the CASE WHEN to apply to the whole query but am struggling to get it right.

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  • Querying Postgresql with a very large result set

    - by sanity
    In an application I need to query a Postgres DB where I expect tens or even hundreds of millions of rows in the result set. I might do this query once a day, or even more frequently. The query itself is relatively simple, although may involve a few JOINs. My question is: How smart is Postgres with respect to avoiding having to seek around the disk for each row of the result set? Given the time required for a hard disk seek, this could be extremely expensive. If this isn't an issue, how does Postgres avoid it? How does it know how to lay out data on the disk such that it can be streamed out in an efficient manner in response to this query?

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  • Android onActivityResult is always 0

    - by Dean
    This has been killing me for two days now. I have a main Activity A which calls a second Activity B. Activity B simply presents the user with a listview. When I press an item on the list view I want a couple of strings to be passed back to the main Activity A and Activiy B will finish. The problem is I always get a resultcode of 0 and the data bundle is null. I really don't understand why this is happening. Here is my code. Start Activity B for result; Test.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Intent i = new Intent(recipeActivity.this, BrowseLoadRecipes.class); startActivityForResult(i, RECIPE_CHOOSER); } }); This starts the second Activity fine. Activity B populates a listview and when I click an item I'm trying to send some data back to the calling Activity A. Any text at the moment, so I used the following in Activity B; lv.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> a, View v, int position, long id) { Bundle bundle = new Bundle(); bundle.putString("TEXT", "Please work... pleeeeaasee"); Intent mIntent = new Intent(); mIntent.putExtras(bundle); setResult(RESULT_OK, mIntent); finish(); } }); In the calling activity I have the following listening for the return as follows; protected void onActivityResult(int requestCode, int resultCode, Intent data) { switch(requestCode) { //TODO case RECIPE_CHOOSER: Toast.makeText(getApplicationContext(), "In recipe return", Toast.LENGTH_SHORT).show(); Toast.makeText(getApplicationContext(), "resultCode is " + String.valueOf(resultCode), Toast.LENGTH_SHORT).show(); if (resultCode == RESULT_OK) { Bundle b = getIntent().getExtras(); Toast.makeText(getApplicationContext(), "Returned " + b.getString("TEXT"), Toast.LENGTH_LONG).show(); } if (resultCode == RESULT_CANCELED) { } break; } } } I can see that the request code is correctly returned, but the resultcode is always a 0 and the data is always a null. I've ran through the debug and the setResult is doing its job and the bundle does indeed have the data I'm passing, but it's lost at some point along the way. Is there something in the manifest I'm missing or something. It's killed my progress on this project so far. Any help would truly be appreciated. Thanks, Dean

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  • SOAP call with query on result (SSRS, Sharepoint)

    - by Erik404
    Hi! I created a report in VS using a shared data source which is connected to a sharepoint list. In the report I created a dataset with a SOAP call to the data source so I get the result from the sharepoint list in a table. this is the soap call <Query> <SoapAction>http://schemas.microsoft.com/sharepoint/soap/GetListItems</SoapAction> <Method Namespace="http://schemas.microsoft.com/sharepoint/soap/" Name="GetListItems"> <Parameters> <Parameter Name="listName"> <DefaultValue>{BD8D39B7-FA0B-491D-AC6F-EC9B0978E0CE}</DefaultValue> </Parameter> <Parameter Name="viewName"> <DefaultValue>{E2168426-804F-4836-9BE4-DC5F8D08A54F}</DefaultValue> </Parameter> <Parameter Name="rowLimit"> <DefaultValue>9999</DefaultValue> </Parameter> </Parameters> </Method> <ElementPath IgnoreNamespaces="True">*</ElementPath> </Query> THis works fine, I have a result which I can show in a report, but I want to have the ability to select a parameter to filter the result on. I have created a parameter and when I preview the Report I see the dropdownbox which I can use to make a selection from the Title field, when I do this it still shows the first record, obviously it doens't work yet (DUH!) because I need to create a query somewhere, But! I have no idea where, I tried to include <Where> <Eq> <FieldRef Name="ows_Title" /> <Value Type="Text">testValue</Value> </Eq> </Where> in the the soap request but it didn't worked... I've searched teh intarwebz but couldn't find any simliar problems... kinda stuck now...any thoughts on this? EDIT Here's the query I used according to the blogpost Alex Angas linked. <Query> <SoapAction>http://schemas.microsoft.com/sharepoint/soap/GetListItems</SoapAction> <Method Namespace="http://schemas.microsoft.com/sharepoint/soap/" Name="GetListItems"> <queryOptions></queryOptions> <query><Query> <Where> <Eq> <FieldRef Name="ows_Title"/> <Value Type="Text">someValue</Value> </Eq> </Where> </Query></query> <Parameters> <Parameter Name="listName"> <DefaultValue>{BD8D39B7-FA0B-491D-AC6F-EC9B0978E0CE}</DefaultValue> </Parameter> <Parameter Name="viewName"> <DefaultValue>{E2168426-804F-4836-9BE4-DC5F8D08A54F}</DefaultValue> </Parameter> <Parameter Name="rowLimit"> <DefaultValue>9999</DefaultValue> </Parameter> </Parameters> </Method> <ElementPath IgnoreNamespaces="True">*</ElementPath> </Query> I tried to put the new query statement in every possible way in the existing, but it doesn't work at all, I do not get an error though so the code is valid, but I still get an unfiltered list as return... pulling my hair out here!

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  • Trying to run a codeigniter app on custom php

    - by hamstar
    I have a CodeIgniter app that I deployed to a server with php 5.2 and my dev box has 5.3, and some stuff doesn't work anymore. I didn't want to upgrade php and risk the other app on the server having issues. Anyway I compiled a custom PHP and added the following to a single .conf file in /etc/httpd/conf.d/zcid.conf with all the other conf files. <VirtualHost *:80> DocumentRoot /var/www/cid/app ServerName sub.example.co.nz </VirtualHost> <Directory "/var/www/cid/app"> authtype Basic authname "oh dear how did this get here i am no good with computer" authuserfile /path/to/auth require valid-user RewriteEngine on RewriteCond $1 !^(index\.php|robots\.txt|createEvent\.php|/cgi-bin) RewriteRule ^(.*)$ /index.php/$1 [L] AddHandler custom-php .php Action custom-php /cgi-bin/php53.cgi </Directory> In /var/www/cid/app I have the cgi-bin folder and the php53.cgi that I copied from /usr/local/php53/bin/php-cgi But now when I navigate to the subdomain it says: The requested URL /cgi-bin/php53.cgi/index.php/ was not found on this server. And if I try to browse to /cgi-bin it says (what it is supposed to?): You don't have permission to access /cgi-bin/ on this server. Quite confused now. Anyone know what to do here? Thanks :)

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  • CloudFront with Custom Origin and ELB

    - by kmfk
    We are using CloudFront for our static assets but also wanted to allow for Gzip. We set up a new distribution with a custom origin pointing back to our application servers which are behind a elastic load balancer. We manually keep the files in sync across the cluster and update them when we publish. However, with this set up, we get nothing but Miss and RefreshHits from CloudFront, which so far has defeated the purpose. Is there any additional settings in order to use an ELB as your custom origin? In the docs, it references this as a viable solution. It appears when we point the distribution to a single server in our production cluster, cloudfront properly caches our assets. Is it possible that the sticky sessions cookie and the subsequent header that gets added by it could be an issue? Cache-Control: no-cache="set-cookie" //Added by load balancer Any ideas? FYI - currently, we have our custom origin pointing to a single EC2 instance, so caching is working correctly - in case you try to curl the file below. Example headers: curl -I http://static.quick-cdn.com/css/9850999.css HTTP/1.0 200 OK Accept-Ranges: bytes Cache-Control: max-age=3700 Cache-Control: no-cache="set-cookie" Content-Length: 23038 Content-Type: text/css Date: Thu, 12 Apr 2012 23:03:52 GMT Last-Modified: Thu, 12 Apr 2012 23:00:14 GMT Server: Apache/2.2.17 (Ubuntu) Vary: Accept-Encoding X-Cache: RefreshHit from cloudfront X-Amz-Cf-Id: K_q7Zy3_jdzlEJ85ukELVtdx1GmuXqApAbZZ7G0fPt0mxRMqPKX5pQ==,RzJmPku-rEIO9WlvuSoKa8hiAaR3dLk5KC4cQMWWrf_MDhmjWe8n6A== Via: 1.0 28c34f9fbf559a21ee16594849e4fc9c.cloudfront.net (CloudFront) Connection: close

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  • How to make quicksilver remember custom trigger

    - by corroded
    I am trying to make a custom trigger for my shell/apple script file to run so I can just launch my dev environment at the push of a button. So basically: I have a shell script(and some apple script included) in ~ named start_server.sh which does 3 things: start up solr server start up memcached start up script/server I have a saved quicksilver command(.qs) that opens up start_server.sh(so start_server.sh, then the action is "Run in Terminal") I created a custom trigger that calls this saved qs command. I did that then tested it and it works. I then tried to double check it so I quit quicksilver and when I checked the triggers it just said: "Open (null)" as the action. I set the trigger again and when i restarted QS the same thing happened again. I don't know why but my old custom trigger to open terminal has worked since forever so why doesn't this one work? Here's a screenie of the triggers after I restart QS: http://grab.by/4XWW If you have any other suggestion on how to make a "push button" start for my server then please do so :) Thanks! As an added note, I have already tried the steps on this thread but to no avail: http://groups.google.com/group/blacktree-quicksilver/browse_thread/thread/7b65ecf6625f8989

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  • MS Word custom dictionary making spellcheck slow - ideas?

    - by ezuk
    I have a user who edits technical materials. She uses MS Word's Custom Dictionary all the time for spelling; it has grown very large, and is now making spell check very slow. All of the advice I've read online says to disable the custom dictionary. This is an easy solution, but is not workable for the user, because she actually needs this dictionary. So, is there any way to optimize the custom dictionary and/or Word itself, so that a large dictionary file doesn't slow things down quite so badly? Many thanks. Update after suggestions: I ran contig on the file, and it reports just 1 frag, so that's not the issue I think. The file is 9.95KB -- 1,117 lines, each consisting of just a single word. I viewed the file using Notepad and none of the lines seems corrupted, strange, or overly long (no line seems to be over 10 chars or so). Both of your suggestions were helpful so I will upvote both; any further tips would be most welcome.

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  • Can google “see” this custom javascript code which displays links from an external site to mine

    - by webmasters
    I have a javascript code on my site who displays links from another site. This is what I have on my source before: <script language="JavaScript" type="text/javascript">showLink(1);</script> This is what I have copied from my source after the page has loaded: <script language="JavaScript" type="text/javascript">showLink(1);</script><a rel="nofollow" target="_blank" class="anc" href="http://x5.external_site.net/sc/out.php?s=5483&amp;o=http%3A%2F%2Fwww.bluetooth.com">Bluetooth Devices</a> Can google see this link?

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  • How to analyze 'dbcc memorystatus' result in SQL Server 2008

    - by envykok
    Currently i am facing a sql memory pressure issue. i have run 'dbcc memorystatus', here is part of my result: Memory Manager KB VM Reserved 23617160 VM Committed 14818444 Locked Pages Allocated 0 Reserved Memory 1024 Reserved Memory In Use 0 Memory node Id = 0 KB VM Reserved 23613512 VM Committed 14814908 Locked Pages Allocated 0 MultiPage Allocator 387400 SinglePage Allocator 3265000 MEMORYCLERK_SQLBUFFERPOOL (node 0) KB VM Reserved 16809984 VM Committed 14184208 Locked Pages Allocated 0 SM Reserved 0 SM Committed 0 SinglePage Allocator 0 MultiPage Allocator 408 MEMORYCLERK_SQLCLR (node 0) KB VM Reserved 6311612 VM Committed 141616 Locked Pages Allocated 0 SM Reserved 0 SM Committed 0 SinglePage Allocator 1456 MultiPage Allocator 20144 CACHESTORE_SQLCP (node 0) KB VM Reserved 0 VM Committed 0 Locked Pages Allocated 0 SM Reserved 0 SM Committed 0 SinglePage Allocator 3101784 MultiPage Allocator 300328 Buffer Pool Value Committed 1742946 Target 1742946 Database 1333883 Dirty 940 In IO 1 Latched 18 Free 89 Stolen 408974 Reserved 2080 Visible 1742946 Stolen Potential 1579938 Limiting Factor 13 Last OOM Factor 0 Page Life Expectancy 5463 Process/System Counts Value Available Physical Memory 258572288 Available Virtual Memory 8771398631424 Available Paging File 16030617600 Working Set 15225597952 Percent of Committed Memory in WS 100 Page Faults 305556823 System physical memory high 1 System physical memory low 0 Process physical memory low 0 Process virtual memory low 0 Procedure Cache Value TotalProcs 11382 TotalPages 430160 InUsePages 28 Can you lead me to analyze this result ? Is it a lot execute plan have been cached causing the memory issue or other reasons?

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  • jQuery Ajax Error Handling – How To Show Custom Error Messages

    - by schnieds
    So you want to make your error feedback nice for your users…Kind of an ironic statement isn’t it? We obviously want to avoid errors if at all possible in our applications, but when errors do occur then we want to provide some nice feedback to our users. The worst thing that can happen is to blow up a huge server exception page when something goes wrong or equally bad is not providing any feedback at all and leaving the user in the dark. Although I do not recommend displaying actual .NET Framework exception messages or stack traces to the user in most instances; they are usually not helpful to the user and can be a security concern.... [Read More]Aaron Schniederhttp://www.churchofficeonline.com

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  • Access UIButton's titleLabel with custom background image

    - by Meltemi
    Quick one: I have a custom button image that I want to use but I still want to change the text of the button with setTitle:forState:. When I use a "custom" button in IB I lose the Title view. When I use Rounded Rect in IB the custom image appears scrunched w/in the Rounded Rect button. Why is this so difficult?

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  • Prevent Custom Entity being deleted from Entity Framework during Update Model Wizard

    - by rbg
    In Entity Framework v1 If you create a Custom Entity to map it to a Stored Procedure during FunctionImport and then Select "Update Model from Database" the Update Model Wizard removes the Custom Entity (as added Manually in the SSDL XML prior to functionImport) from the SSDL. Does anyone know if this limitation has been dealt with Entity Framework v4? I mean is there a way to prevent the Wizard from removing the Custom Entity from the Storage Schema (SSDL) during Model Update from Database????

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  • Custom UIView built with Interface Builder accessible/positionable via Interface Builder

    - by Nader
    This shouldn't be this confusing. I have a custom UIView with a bunch on controls on it. UILabels, buttons, etc. I've created this Nib using Interface Builder. I want to be able to position this custom uiview on another UIView using the interface builder. How do I link my UIView custom class, to the nib? initWithCoder gets called, but I want this class to get loaded from the nib. Thanks

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  • Professional Custom Logo Design vs. Mr. Right

    John is an ex-marine and ex-employee of general motors. He recently lost his job working as a welder on the assembly lines of one of GM manufacturing plants. John has traveled a lot and knows a lot a... [Author: Emily Matthew - Web Design and Development - March 31, 2010]

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  • How to use Blazeds with a custom classloader?

    - by festerwim
    Hi, has anybody tried using a custom classloader with BlazeDS? We have a web application using BlazeDS and we can convert Java objects in to ActionScript object and back without problems in the main application. However, we also have a plug-in mechanism based on a custom classloader. BlazeDS cannot map the types contained in jar files of that custom classloader since I don't know how to tell it to BlazeDS. Has anybody already done this? The livedocs of TypeMarshallingcontext show a setClassloader() method, but since the context seems to be a singleton, I assume this will not work if you have multiple custom classloaders (we have 1 for each plugin that is deployed) regards, Wim

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  • A couple of questions on exceptions/flow control and the application of custom exceptions

    - by dotnetdev
    1) Custom exceptions can help make your intentions clear. How can this be? The intention is to handle or log the exception, regardless of whether the type is built-in or custom. The main reason I use custom exceptions is to not use one exception type to cover the same problem in different contexts (eg parameter is null in system code which may be effect by an external factor and an empty shopping basket). However, the partition between system and business-domain code and using different exception types seems very obvious and not making the most of custom exceptions. Related to this, if custom exceptions cover the business exceptions, I could also get all the places which are sources for exceptions at the business domain level using "Find all references". Is it worth adding exceptions if you check the arguments in a method for being null, use them a few times, and then add the catch? Is it a realistic risk that an external factor or some other freak cause could cause the argument to be null after being checked anyway? 2) What does it mean when exceptions should not be used to control the flow of programs and why not? I assume this is like: if (exceptionVariable != null) { } Is it generally good practise to fill every variable in an exception object? As a developer, do you expect every possible variable to be filled by another coder?

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  • Using NServiceBus behind a custom web service

    - by Michael Stephenson
    In this post I'd like to talk about an architecture scenario we had recently and how we were able to utilise NServiceBus to help us address this problem. Scenario Cognos is a reporting system used by one of my clients. A while back we developed a web service façade to allow line of business applications to be able to access reports from Cognos to support their various functions. The service was intended to provide access to reports which were quick running reports or pre-generated reports which could be accessed real-time on demand. One of the key aims of the web service was to provide a simple generic interface to allow applications to get any report without needing to worry about the complex .net SDK for Cognos. The web service also supported multi-hop kerberos delegation so that report data could be accesses under the context of the end user. This service was working well for a period of time. The Problem The problem we encountered was that reports were now also required to be available to batch processes. The original design was optimised for low latency so users would enjoy a positive experience, however when the batch processes started to request 250+ concurrent reports over an extended period of time you can begin to imagine the sorts of problems that come into play. The key problems this new scenario caused are: Users may be affected and the latency of on demand reports was significantly slower The Cognos infrastructure was not scaled sufficiently to be able to cope with these long peaks of load From a cost perspective it just isn't feasible to scale the Cognos infrastructure to be able to handle the load when it is only for a couple of hour window each night. We really needed to introduce a second pattern for accessing this service which would support high through-put scenarios. We also had little control over the batch process in terms of being able to throttle its load. We could however make some changes to the way it accessed the reports. The Approach My idea was to introduce a throttling mechanism between the Web Service Façade and Cognos. This would allow the batch processes to push reports requests hard at the web service which we were confident the web service can handle. The web service would then queue these requests and process them behind the scenes and make a call back to the batch application to provide the report once it had been accessed. In terms of technology we had some limitations because we were not able to use WCF or IIS7 where the MSMQ-Activated WCF services could have helped, but we did have MSMQ as an option and I thought NServiceBus could do just the job to help us here. The flow of how this would work was as follows: The batch applications would send a request for a report to the web service The web service uses NServiceBus to send the message to a Queue The NServiceBus Generic Host is running as a windows service with a message handler which subscribes to these messages The message handler gets the message, accesses the report from Cognos The message handler calls back to the original batch application, this is decoupled because the calling application provides a call back url The report gets into the batch application and is processed as normal This approach looks something like the below diagram: The key points are an application wanting to take advantage of the batch driven reports needs to do the following: Implement our call back contract Make a call to the service providing a call back url Provide a correlation ID so it knows how to tie each response back to its request What does NServiceBus offer in this solution So this scenario is not the typical messaging service bus type of solution people implement with NServiceBus, but it did offer the following: Simplified interaction with MSMQ Offered the ability to configure the number of processes working through the queue so we could find a balance between load on Cognos versus the applications end to end processing time NServiceBus offers retries and a way to manage failed messages NServiceBus offers a high availability setup The simple thing is that NServiceBus gave us the platform to build the solution on. We just implemented a message handler which functionally processed a message and we could rely on NServiceBus to do all of the hard work around managing the queues and all of the lower level things that would have took ages to write to any kind of robust level. Conclusion With this approach we were able to deal with a fairly significant performance issue with out too much rework. Hopefully this write up gives people some insight into ideas on how to leverage the excellent NServiceBus framework to help solve integration and high through-put scenarios.

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