Search Results

Search found 10033 results on 402 pages for 'execution speed'.

Page 335/402 | < Previous Page | 331 332 333 334 335 336 337 338 339 340 341 342  | Next Page >

• What would you write in a consitution (law book) for a programmers' country?

  - by Developer Art

  After we have got our great place to talk about professional matters and sozialize online - on SO, I believe the next logical step would be to found our own country! I invite you all to participate and bring together your available resources. We will buy an island, better even a group of island so that we could establish states like .NET territories, Java land, Linux republic etc. We will build a society of programmers (girls - we need you too). To the organizational side, we're going to need some constitution or a law book. I suggest we write it together. I make it a wiki as it should be a cooperative effort. I'll open the work. Section 1. Programmers' rights. Every citizen has a right to an Internet connection 24/7. Every citizen can freely choose the field of interest Section 2. Programmers' obligations. Every citizen must embrace the changing nature of the profession and constanly educate himself Section 3. Law enforcement. Code duplication when can be avoided is punished by limiting the bandwith speed to 64Kbit for a period of one week. Using ugly hacks instead of refactoring code is punished by cutting the Internet connection for a period of one month. Usage of technologies older than 5/10 years is punished by restricting the web access to the sites last updated 5/10 years ago for a period of one month. Please feel free to modify and extend the list. We'll need to have it ready before we proceed formally with the country foundation. A purchase fund will be established shortly. Everyone is invited to participate.

  Read the article

• BPEL, initialize variable and repeating onAlarm eventHandler

  - by Michael

  I have a little problem I can't solve so far. In BPEL I want to create an onAlarm eventHandler which fires immediatly (i.e. the "for" element is set to 'PT0S') and repeats every 2 seconds. This eventHandler shall contain a counter which increments every time the alarm fires. The question is: How to initialize the counter? If the variable will be initialized within the onAlarm scope the value would not increment anymore. In the "normal" control flow the value also cannot be initialized, because it is not defined if the process or the onAlarm scope runs first. So I would get every now and then an uninitializedVariable exception. My solution would be to not initialize the variable neither in the process scope nor in the onAlarm scope, but create a faultHandler wherein the variable will be initialized and afterwards the onAlarm flow will be executed. Problem is every uninitializedVariable execution will be caught now by this faultHandler and there may be another too. So is there another possibility to deal with this problem or can I somehow find out which variable wasn't initialized properly so the faultHandler can get two control flows? The solution should work on every BPEL engine. Thanks, Michael

  Read the article

• Mysql select - improve performance

  - by realshadow

  Hey, I am working on an e-shop which sells products only via loans. I display 10 products per page in any category, each product has 3 different price tags - 3 different loan types. Everything went pretty well during testing time, query execution time was perfect, but today when transfered the changes to the production server, the site "collapsed" in about 2 minutes. The query that is used to select loan types sometimes hangs for ~10 seconds and it happens frequently and thus it cant keep up and its hella slow. The table that is used to store the data has approximately 2 milion records and each select looks like this: SELECT * FROM products_loans WHERE KOD IN("X17/Q30-10", "X17/12", "X17/5-24") AND 369.27 BETWEEN CENA_OD AND CENA_DO; 3 loan types and the price that needs to be in range between CENA_OD and CENA_DO, thus 3 rows are returned. But since I need to display 10 products per page, I need to run it trough a modified select using OR, since I didnt find any other solution to this. I have asked about it here, but got no answer. As mentioned in the referencing post, this has to be done separately since there is no column that could be used in a join (except of course price and code, but that ended very, very badly). Here is the show create table, kod and CENA_OD/CENA_DO very indexed via INDEX. CREATE TABLE `products_loans` ( `KOEF_ID` bigint(20) NOT NULL, `KOD` varchar(30) NOT NULL, `AKONTACIA` int(11) NOT NULL, `POCET_SPLATOK` int(11) NOT NULL, `koeficient` decimal(10,2) NOT NULL default '0.00', `CENA_OD` decimal(10,2) default NULL, `CENA_DO` decimal(10,2) default NULL, `PREDAJNA_CENA` decimal(10,2) default NULL, `AKONTACIA_SUMA` decimal(10,2) default NULL, `TYP_VYHODY` varchar(4) default NULL, `stage` smallint(6) NOT NULL default '1', PRIMARY KEY (`KOEF_ID`), KEY `CENA_OD` (`CENA_OD`), KEY `CENA_DO` (`CENA_DO`), KEY `KOD` (`KOD`), KEY `stage` (`stage`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 And also selecting all loan types and later filtering them trough php doesnt work good, since each type has over 50k records and the select takes too much time as well... Any ides about improving the speed are appreciated.

  Read the article

• Generate and merge data with python multiprocessing

  - by Bobby

  I have a list of starting data. I want to apply a function to the starting data that creates a few pieces of new data for each element in the starting data. Some pieces of the new data are the same and I want to remove them. The sequential version is essentially: def create_new_data_for(datum): """make a list of new data from some old datum""" return [datum.modified_copy(k) for k in datum.k_list] data = [some list of data] #some data to start with #generate a list of new data from the old data, we'll reduce it next newdata = [] for d in data: newdata.extend(create_new_data_for(d)) #now reduce the data under ".matches(other)" reduced = [] for d in newdata: for seen in reduced: if d.matches(seen): break #so we haven't seen anything like d yet seen.append(d) #now reduced is finished and is what we want! I want to speed this up with multiprocessing. I was thinking that I could use a multiprocessing.Queue for the generation. Each process would just put the stuff it creates on, and when the processes are reducing the data, they can just get the data from the Queue. But I'm not sure how to have the different process loop over reduced and modify it without any race conditions or other issues. What is the best way to do this safely? or is there a different way to accomplish this goal better?

  Read the article

• Poor performance using RMI-proxies with Swing components

  - by Patrick

  I'm having huge performance issues when I add RMI proxy references to a Java Swing JList-component. I'm retrieving a list of user Profiles with RMI from a server. The retrieval itself takes just a second or so, so that's acceptable under the circumstances. However, when I try to add these proxies to a JList, with the help of a custom ListModel and a CellRenderer, it takes between 30-60 seconds to add about 180 objects. Since it is a list of users' names, it's preferrable to present them alphabetically. The biggest performance hit is when I sort the elements as they get added to the ListModel. Since the list will always be sorted, I opted to use the built-in Collections.binarySearch() to find the correct position for the next element to be added, and the comparator uses two methods that are defined by the Profile interface, namely getFirstName() and getLastName(). Is there any way to speed this process up, or am I simply implementing it the wrong way? Or is this a "feature" of RMI? I'd really love to be able to cache some of the data of the remote objects locally, to minimize the remote method calls.

  Read the article

• Scheme: what are the benefits of letrec?

  - by Ixmatus

  While reading "The Seasoned Schemer" I've begun to learn about letrec. I understand what it does (can be duplicated with a Y-Combinator) but the book is using it in lieu of recurring on the already defined function operating on arguments that remain static. An example of an old function using the defined function recurring on itself (nothing special): (define (substitute new old lat) (cond ((null? l) '()) ((eq? (car l) old) (cons new (substitute new old (cdr l)))) (else (cons (car l) (substitute new old (cdr l)))))) Now for an example of that same function but using letrec: (define (substitute new old lat) (letrec ((replace (lambda (l) (cond ((null? l) '()) ((eq? (car l) old) (cons new (replace (cdr l)))) (else (cons (car l) (replace (cdr l)))))))) (replace lat))) Aside from being slightly longer and more difficult to read I don't know why they are rewriting functions in the book to use letrec. Is there a speed enhancement when recurring over a static variable this way because you don't keep passing it?? Is this standard practice for functions with arguments that remain static but one argument that is reduced (such as recurring down the elements of a list)? Some input from more experienced Schemers/LISPers would help!

  Read the article

• Changing the indexing on existing table in SQL Server 2000

  - by Raj

  Guys, Here is the scenario: SQL Server 2000 (8.0.2055) Table currently has 478 million rows of data. The Primary Key column is an INT with IDENTITY. There is an Unique Constraint imposed on two other columns with a Non-Clustered Index. This is a vendor application and we are only responsible for maintaining the DB. Now the vendor has recommended doing the following "to improve performance" Drop the PK and Clustered Index Drop the non-clustered index on the two columns with the UNIQUE CONSTRAINT Recreate the PK, with a NON-CLUSTERED index Create a CLUSTERED index on the two columns with the UNIQUE CONSTRAINT I am not convinced that this is the right thing to do. I have a number of concerns. By dropping the PK and indexes, you will be creating a heap with 478 million rows of data. Then creating a CLUSTERED INDEX on two columns would be a really mammoth task. Would creating another table with the same structure and new indexing scheme and then copying the data over, dropping the old table and renaming the new one be a better approach? I am also not sure how the stored procs will react. Will they continue using the cached execution plan, considering that they are not being explicitly recompiled. I am simply not able to understand what kind of "performance improvement" this change will provide. I think that this will actually have the reverse effect. All thoughts welcome. Thanks in advance, Raj

  Read the article

• Mysql and PHP - Reading multiple insert queries from a file and executing at runtime

  - by SpikETidE

  Hi everyone... I am trying out a back-up and restore system. Basically, what i try to do is, when creating the back up i make a file which looks like DELETE FROM bank_account; INSERT INTO bank_account VALUES('1', 'IB6872', 'Indian Bank', 'Indian Bank', '2', '1', '0', '0000-00-00 00:00:00', '1', '2010-04-13 17:09:05');INSERT INTO bank_account VALUES('2', 'IB7391', 'Indian Bank', 'Indian Bank', '3', '1', '0', '0000-00-00 00:00:00', '1', '2010-04-13 17:09:32'); and so on and so forth. When i restore the db i just read the query from the file, save it to a string and then execute it over the DB using mysql_query(); The problem is, when i run the query through mysql_query(), the execution stops after the delete query with the error 'Error in syntax near '; INSERT INTO bank_account VALUES('1', 'IB6872', 'Indian Bank', 'Indian Bank', '2',' at line 1. But when i run the queries directly over the Db, using phpmyadmin it executes without any errors. As far as i can see, i can't notice any syntax error in the query. Can anyone point out where there might be a glitch...? Thanks and regards....

  Read the article

• XMLHttpRequest() and Google Analytics Tracking

  - by sjw

  I have implemented an XMLHttpRequest() call to a standalone html page which simply has an html, title & body tag which Google Analytics Tracking code. I want to track when someone makes a request to display information (i.e. phone number) to try and understand what portion of people look at my directory versus obtaining a phone number to make a call. It is very simple code: var xhReq = new XMLHttpRequest(); xhReq.open("GET", "/registerPhoneClick.htm?id=" + id, false); xhReq.send(null); var serverResponse = xhReq.responseText Yet I cannot see the "hit" in Analytics... Has anyone had this issue? All the analytics tracking code does is call: <script type="text/javascript"> var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www."); document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E")); </script> <script type="text/javascript"> try { var pageTracker = _gat._getTracker("UA-XXXXXXX"); pageTracker._trackPageview(); } catch(err) {}</script> So realistically, my XmlHTTPRequest() calls an htm file within which a script is execute to make an outbound call to Google Analytics. Is there any reason why an XmlHTTPRequest() would not execute this? Does an XmlHTTPRequest() still bring the code to the client before execution? Help Please

  Read the article

• Web framework with JasperReports integration?

  - by Dave Jarvis

  What web development frameworks natively support JasperReports? Consider the following form as an example: <form name="report" method="post"> <input type="hidden" name="REPORT_PATH" value="reports/Names" /> <input type="hidden" name="REPORT_FILE" value="List" /> <input type="hidden" name="REPORT_FORMAT" value="pdf" /> <input type="hidden" name="REPORT_EMBED" value="false" /> Name: <input type="text" name="report_Name" value="" /><br /> Date: <input type="text" name="report_Date" value="" /><br /> <input type="submit" name="View" value="View" /> </form> The framework would pass the report_ parameters to JasperReports, which in turn runs reports/Names/List.jasper, and then sends a PDF attachment to the browser. In general: Ability to configure report (i.e., the hidden REPORT_ variables) Web FORM for setting report parameters (i.e., the report_ variables) Framework handles configuring database connection, report execution, etc. I don't care about the technical minutia on how the integration works. The example above is just one possibility of many.

  Read the article

• how can we apply client side validation on fileupload control in ASP.NET to check filename contain s

  - by subodh

  I am working on ASP.NET3.5 platform. I have used a file upload control and a asp button to upload a file. Whenever i try to upload a file which contain special characterlike (file#&%.txt) it show crash and give the messeage Server Error in 'myapplication' Application. A potentially dangerous Request.Files value was detected from the client (filename="...\New Text &#.txt"). Description: Request Validation has detected a potentially dangerous client input value, and processing of the request has been aborted. This value may indicate an attempt to compromise the security of your application, such as a cross-site scripting attack. You can disable request validation by setting validateRequest=false in the Page directive or in the configuration section. However, it is strongly recommended that your application explicitly check all inputs in this case. Exception Details: System.Web.HttpRequestValidationException: A potentially dangerous Request.Files value was detected from the client (filename="...\New Text &#.txt"). Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. how can i prevent this crash using javascript at client side?

  Read the article

• C++ Exception Handling

  - by user1413793

  So I was writing some code and I noticed that apart from syntactical, type, and other compile-time errors, C++ does not throw any other exceptions. So I decided to test this out with a very trivial program: #include<iostream> int main() { std::count<<5/0<<std::endl; return 1 } When I compiled it using g++, g++ gave me a warning saying I was dividing by 0. But it still compiled the code. Then when I ran it, it printed some really large arbitrary number. When I want to know is, how does C++ deal with exceptions? Integer division by 0 should be a very trivial example of when an exception should be thrown and the program should terminate. Do I have to essentially enclose my entire program in a huge try block and then catch certain exceptions? I know in Python when an exception is thrown, the program will immediately terminate and print out the error. What does C++ do? Are there even runtime exceptions which stop execution and kill the program?

  Read the article

• Recommend me an architecture for this Facebook application

  - by andybaird

  Firstly, this question is subjective. There is not a right answer for this question and it really depends on what works for you. I'm hoping to use this thread as a breeding ground for ideas. I hope this is acceptable in this medium. I'm working on building a Facebook app that will be replacing an already popular app that gets ~50k hits a day. The original app is using a very typical LAMP setup with help from some Zend libraries for database layer extraction. For the most part the app worked well, except to solve a lot of issues I ended up fragmenting tables to speed things up. As a result, I couldn't do a lot of things with the app that I wanted to (namely any processing using aggregate data that needed to be returned quickly) So I'm starting to design plans for the next version of this application, and I have a whole bunch of new and cool features that I know would choke my current setup. I'm looking for technological recommendations of data storage methods that scale well. The database does not necessarily need to be relational, simple key/value storage would suffice (although at present time I know little to nothing about KV stores) What's your recommendation? How would you tackle this? I'd like to take a completely free approach to this -- although I am most familiar and comfortable using PHP, I want to leave all technical options open.

  Read the article

• Does adding to a method group count as using a variable?

  - by Vaccano

  I have the following code example taken from the code of a Form: protected void SomeMethod() { SomeOtherMethod(this.OnPaint); } private void SomeOtherMethod(Action<PaintEventArgs> onPaint) { onPaint += MyPaint; } protected void MyPaint(PaintEventArgs e) { // paint some stuff } The second method (SomeOtherMethod) has resharper complaining at me. It says of onPaint that "Value assigned is not used in any execution path". To my mind it was used because I added a method to the list of methods called when a paint was done. But usually when resharper tells me something like this it is because I am not understanding some part of C#. Like maybe when the param goes out of goes out of scope the item I added to the list gets removed (or something like that). I thought I would ask here to see if any one knows what resharper is trying to tell me. (Side Note: I usually just override OnPaint. But I am trying to get OnPaint to call a method in another class. I don't want to expose that method publicly so I thought I would pass in the OnPaint group and add to it.)

  Read the article

• jQuery e.target bubbling best practice ?

  - by olouv

  In my heavy-ajax code, i always bind "click" the body tag & act depending on $(e.target) & using $.fn.hasClass(). However when i click on an anchor that has a </span> tag inside, my $(e.target) equals this node, and not the parent anchor as i would like it to. From now on, i have used this trick (var $t = $(e.target);) : /** bubbling **/ if($t.get(0).tagName !== "A" && $t.get(0).tagName !== "AREA") { $t = $t.parent("a"); if(empty($t)) return true; //else console.log("$t.bubble()", $t); } It feels wrong somehow... Do you have any better implementation ? $.fn.live() does not solve my issue as it still returns the span as the target. Moreover i'm looking for speed (running on atom-based touch devices) & live appeared to be way slower (twice) : http://jsperf.com/bind-vs-click/3 In fact, as @Guffa pointed, using $.fn.live() solves the span bubbling issue as i don't need the event.target anymore. I guess there is no other "right" answer here (using bind).

  Read the article

• How does static code run with multiple threads?

  - by Krisc

  I was reading http://stackoverflow.com/questions/1511798/threading-from-within-a-class-with-static-and-non-static-methods and I am in a similar situation. I have a static method that pulls data from a resource and creates some runtime objects based on the data. static class Worker{ public static MyObject DoWork(string filename){ MyObject mo = new MyObject(); // ... does some work return mo; } } The method takes awhile (in this case it is reading 5-10mb files) and returns an object. I want to take this method and use it in a multiple thread situation so I can read multiple files at once. Design issues / guidelines aside, how would multiple threads access this code? Let's say I have something like this... class ThreadedWorker { public void Run() { Thread t = new Thread(OnRun); t.Start(); } void OnRun() { MyObject mo = Worker.DoWork("somefilename"); mo.WriteToConsole(); } } Does the static method run for each thread, allowing for parallel execution?

  Read the article

• How to benchmark on multi-core processors

  - by Pascal Cuoq

  I am looking for ways to perform micro-benchmarks on multi-core processors. Context: At about the same time desktop processors introduced out-of-order execution that made performance hard to predict, they, perhaps not coincidentally, also introduced special instructions to get very precise timings. Example of these instructions are rdtsc on x86 and rftb on PowerPC. These instructions gave timings that were more precise than could ever be allowed by a system call, allowed programmers to micro-benchmark their hearts out, for better or for worse. On a yet more modern processor with several cores, some of which sleep some of the time, the counters are not synchronized between cores. We are told that rdtsc is no longer safe to use for benchmarking, but I must have been dozing off when we were explained the alternative solutions. Question: Some systems may save and restore the performance counter and provide an API call to read the proper sum. If you know what this call is for any operating system, please let us know in an answer. Some systems may allow to turn off cores, leaving only one running. I know Mac OS X Leopard does when the right Preference Pane is installed from the Developers Tools. Do you think that this make rdtsc safe to use again? More context: Please assume I know what I am doing when trying to do a micro-benchmark. If you are of the opinion that if an optimization's gains cannot be measured by timing the whole application, it's not worth optimizing, I agree with you, but I cannot time the whole application until the alternative data structure is finished, which will take a long time. In fact, if the micro-benchmark were not promising, I could decide to give up on the implementation now; I need figures to provide in a publication whose deadline I have no control over.

  Read the article

• AI navigation around a 2d map - Avoiding obstacles.

  - by Curt Walker

  Hey there, I know my question seems pretty vague but I can't think of a better way to put it so I'll start off by explaining what I'm trying to do. I'm currently working on a project whereby I've been given a map and I'm coding a 'Critter' that should be able to navigate it's way around the map, the critter has various other functions but are not relevant to the current question. The whole program and solution is being written in C#. I can control the speed of the critter, and retrieve it's current location on the map by returning it's current X and Y position, I can also set it's direction when it collides with the terrain that blocks it. The only problem I have is that I can't think of a way to intelligently navigate my way around the map, so far I've been basing it around what direction the critter is facing when it collides with the terrain, and this is in no way a good way of moving around the map! I'm not a games programmer, and this is for a software assignment, so I have no clue on AI techniques. All I am after is a push in the right direction on how I could go about getting this critter to find it's way around any map given to me. Here's an image of the map and critters to give you an idea of what i'm talking about. Here's a link to an image of what the maps and critters look like. Map and Critter image I'm in no way looking for anyone to give me a full solution, just a push in the general direction on map navigation. Thanks in advance!

  Read the article

• Jquery Cycle Lite plugin unable to see images that have been loaded by an AJAX call

  - by William Macdonald

  Hi, I am having problems using the jquery cycle lite plugin on some images that are added via AJAX. Here is the jquery code: $(function() { resizeWindow(); $(window).bind("resize", resizeWindow); $("#assignment-nav").accordion({ header: "h3", autoHeight: false }); $(".project").click(function() { // get the HTML and load into div $('.image-holder').empty(); var justTheNumber = $(this).attr('id').replace('project-',''); $.get("get_project_images.php", {project_id:justTheNumber}, function(data){ $('.image-holder').append(data); } ); $(".image-holder").cycle({ // Cycle plugin prev: '#prev', next: '#next', timeout: 0, speed: 250 }) }); }); My code works fine in that the IMG tags are loaded and the first image of the slide show is displayed. However the prev/next buttons don't work. When I load the images via static HTML the slideshow prev/next links works fine. (I just copied and pasted the generated HTML.) I understand I need to use something like .bind or .live to make the Cycle plugin 'see' the new images. I have tried everything I can think of but I can't make it work. What am I doing wrong ?

  Read the article

• Using memory-based cache together with conventional cache

  - by Industrial

  Hi! Here's the deal. We would have taken the complete static html road to solve performance issues, but since the site will be partially dynamic, this won't work out for us. What we have thought of instead is using memcache + eAccelerator to speed up PHP and take care of caching for the most used data. Here's our two approaches that we have thought of right now: Using memcache on all<< major queries and leaving it alone to do what it does best. Usinc memcache for most commonly retrieved data, and combining with a standard harddrive-stored cache for further usage. The major advantage of only using memcache is of course the performance, but as users increases, the memory usage gets heavy. Combining the two sounds like a more natural approach to us, even though the theoretical compromize in performance. Memcached appears to have some replication features available as well, which may come handy when it's time to increase the nodes. What approach should we use? - Is it stupid to compromize and combine the two methods? Should we insted be focusing on utilizing memcache and instead focusing on upgrading the memory as the load increases with the number of users? Thanks a lot!

  Read the article

• C# KeyEvent doesn't log the enter/return key

  - by Pieter888

  Hey all, I've been making this login form in C# and I wanted to 'submit' all the data as soon as the user either clicks on submit or presses the enter/return key. I've been testing a bit with KeyEvents but nothing so far worked. void tbPassword_KeyPress(object sender, KeyPressEventArgs e) { MessageBox.Show(e.KeyChar.ToString()); } The above code was to test if the event even worked in the first place. It works perfectly, when I press 'd' it shows me 'd' when I press '8' it shows me '8' but pressing enter doesn't do anything. So I though this was because enter isn't really bound to a character but it did show backspace, it worked just fine so it got me confused about why it didn't register my enter key. So the question is: How do I log the enter/return key? and why doesn't it log the key press right right now like it should? note: I've put the event in a textbox tbPassword.KeyPress += new KeyPressEventHandler(tbPassword_KeyPress); So it fires when the enter button is pressed WHILE the textbox is selected (which is was the whole time of course) maybe that has something to do with the execution of the code.

  Read the article

• Python Error-Checking Standard Practice

  - by chaindriver

  Hi, I have a question regarding error checking in Python. Let's say I have a function that takes a file path as an input: def myFunction(filepath): infile = open(filepath) #etc etc... One possible precondition would be that the file should exist. There are a few possible ways to check for this precondition, and I'm just wondering what's the best way to do it. i) Check with an if-statement: if not os.path.exists(filepath): raise IOException('File does not exist: %s' % filepath) This is the way that I would usually do it, though the same IOException would be raised by Python if the file does not exist, even if I don't raise it. ii) Use assert to check for the precondition: assert os.path.exists(filepath), 'File does not exist: %s' % filepath Using asserts seems to be the "standard" way of checking for pre/postconditions, so I am tempted to use these. However, it is possible that these asserts are turned off when the -o flag is used during execution, which means that this check might potentially be turned off and that seems risky. iii) Don't handle the precondition at all This is because if filepath does not exist, there will be an exception generated anyway and the exception message is detailed enough for user to know that the file does not exist I'm just wondering which of the above is the standard practice that I should use for my codes.

  Read the article

• Working with complex objects in Prevayler commands

  - by alexantd

  The demos included in the Prevayler distribution show how to pass in a couple strings (or something simple like that) into a command constructor in order to create or update an object. The problem is that I have an object called MyObject that has a lot of fields. If I had to pass all of them into the CreateMyObject command manually, it would be a pain. So an alternative I thought of is to pass my business object itself into the command, but to hang onto a clone of it (keeping in mind that I can't store the BO directly in the command). Of course after executing this command, I would need to make sure to dispose of the original copy that I passed in. public class CreateMyObject implements TransactionWithQuery { private MyObject object; public CreateMyObject(MyObject business_obj) { this.object = (MyObject) business_obj.clone(); } public Object executeAndQuery(...) throws Exception { ... } } The Prevayler wiki says: Transactions can't carry direct object references (pointers) to business objects. This has become known as the baptism problem because it's a common beginner pitfall. Direct object references don't work because once a transaction has been serialized to the journal and then deserialized for execution its object references no longer refer to the intended objects - - any objects they may have referred to at first will have been copied by the serialization process! Therefore, a transaction must carry some kind of string or numeric identifiers for any objects it wants to refer to, and it must look up the objects when it is executed. I think by cloning the passed-in object I will be getting around the "direct object pointer" problem, but I still don't know whether or not this is a good idea...

  Read the article

• Why Android for enterprise applications?

  - by mcabral

  Recently one of our clients is considering the posibility of picking up an old WinMobile 5.0 project. Several features are to be added to the point it will be a major version update. The client is worried about the mobile market, and thinks there's a chance all the effort put in this development will have to be thrown away in a couple of year due to the dinamics of the mobile market and the deprecation of mobile devices. So, the client is not sure whether he should continue with Windows Mobile (changing from WM 5.0 to 6.X) or starting from scratch with another technology. From our part we have been studing the mobile market, looking for clues for which will be the winning horse. The safe move seems to continue with WM just because re writing an entire application from scratch involves more risks and delays. On the other hand WM seems to be losing market and the ghost of an exit on their part is growing stronger everyday. But what can be say about Android? Everyone is talking about it and is growing at full speed but what avantagies will it bring to the table? Why should we start a fresh applicaction on this technology? So the question remains the same.. is Andriod mature enough for an enterprise application? Will you recomend it to one of your clients? Will you port/rewrite a WM application to Andriod? What's the trade-off? EDIT: Addressing commentaries. The app is entirely built with C# and Compact Framework. The app is for logistics/management.

  Read the article

• I need a fast runtime expression parser

  - by Chris Lively

  I need to locate a fast, lightweight expression parser. Ideally I want to pass it a list of name/value pairs (e.g. variables) and a string containing the expression to evaluate. All I need back from it is a true/false value. The types of expressions should be along the lines of: varA == "xyz" and varB==123 Basically, just a simple logic engine whose expression is provided at runtime. UPDATE At minimum it needs to support ==, !=, , =, <, <= Regarding speed, I expect roughly 5 expressions to be executed per request. We'll see somewhere in the vicinity of 100/requests a second. Our current pages tend to execute in under 50ms. Usually there will only be 2 or 3 variables involved in any expression. However, I'll need to load approximately 30 into the parser prior to execution. UPDATE 2012/11/5 Update about performance. We implemented nCalc nearly 2 years ago. Since then we've expanded it's use such that we average 40+ expressions covering 300+ variables on post backs. There are now thousands of post backs occurring per second with absolutely zero performance degradation. We've also extended it to include a handful of additional functions, again with no performance loss. In short, nCalc met all of our needs and exceeded our expectations.

  Read the article

< Previous Page | 331 332 333 334 335 336 337 338 339 340 341 342  | Next Page >