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  • why won't Eclipse use the compiler I specify for my project?

    - by codeman73
    I'm using Eclipse 3.3. In my project, I've set the compiler compliance level to 5.0 In the build path for the project. I've added the Java 1.5 JDK in the Installed JREs section and am referencing that System Library in my project build path. However, I'm getting compile errors for a class that implements PreparedStatement for not implementing abstract methods that only exist in Java 1.6 PreparedStatement. Specifically, the methods setAsciiStream(int, InputStream, long) and setAsciiStream(int, InputStream) Strangely enough, it worked when we were compiling it against Java 1.4, which it was originally written for. We added the JREs for Java 1.4 and referenced that system library in the project, and set the project's compiler level to 1.4, and it works fine. But when I do the same changes to try to point to Java 5.0, it instead uses Java 6. Any ideas why? I wrote a similar question earlier, here: http://stackoverflow.com/questions/2540548/how-do-i-get-eclipse-to-use-a-different-compiler-version-for-java I know how you're supposed to choose a different compiler but it seems Eclipse isn't taking it. It seems to be defaulting to Java 6, even though I have deleted all Java 6 JDKs and JREs that I could find. I've also updated the -vm option in my eclipse.ini to point to the Java5 JDK.

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  • Python multiprocessing doesn't play nicely with uuid.uuid4().

    - by yig
    I'm trying to generate a uuid for a filename, and I'm also using the multiprocessing module. Unpleasantly, all of my uuids end up exactly the same. Here is a small example: import multiprocessing import uuid def get_uuid( a ): ## Doesn't help to cycle through a bunch. #for i in xrange(10): uuid.uuid4() ## Doesn't help to reload the module. #reload( uuid ) ## Doesn't help to load it at the last minute. ## (I simultaneously comment out the module-level import). #import uuid ## uuid1() does work, but it differs only in the first 8 characters and includes identifying information about the computer. #return uuid.uuid1() return uuid.uuid4() def main(): pool = multiprocessing.Pool( 20 ) uuids = pool.map( get_uuid, range( 20 ) ) for id in uuids: print id if __name__ == '__main__': main() I peeked into uuid.py's code, and it seems to depending-on-the-platform use some OS-level routines for randomness, so I'm stumped as to a python-level solution (to do something like reload the uuid module or choose a new random seed). I could use uuid.uuid1(), but only 8 digits differ and I think there are derived exclusively from the time, which seems dangerous especially given that I'm multiprocessing (so the code could be executing at exactly the same time). Is there some Wisdom out there about this issue?

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  • ipad tabbar rotation

    - by MaKo
    hi, please help with this noob questions but really making me go crazy if I create a project from scratch (using windows based app) for the ipad, and add a tabbar , with firstviewController, and secondviewController, it works fine, starts in landscape mode, but in info.plist I set it to Landscape(left home button), but really in simulator starts with the button on the right side! in the FirstViewController.m (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { if (interfaceOrientation == UIInterfaceOrientationLandscapeLeft || interfaceOrientation == UIInterfaceOrientationLandscapeRight) return YES; else { return NO; }} so it starts in landscape, and rotates as the simulator rotates, but if I create a template app for iphone tabbar, set the info.plist Initial interface orientation Landscape (left home button) and add the code above, IT DOESNT WORK!!! simulator starts with button at left but tab bar on the side, same problem that I had with an app that Im porting from iphone to ipad, (landscape intended) I get to the landscape start mode, but the tab bar remains on the side! also the only way to make the old ported app to show the simulator on the side was with UIInterfaceOrientation UIIntefaceOrientationLandscapeLeft (didnt work with Initial interface orientation), does not let me choose the value for the key, but it shows the simulator on landscape,, so,, what can I do please to show the tab bar on landscape mode??? the tabbar from scratch was made to see if the code will work , but it didnt?? why does it work in the tab bar made from windows app and not tab bar app? I just want the tab bar to show in landscape ahhh, thanks

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  • User preferences using SQL and JavaScript

    - by Shyam
    Hi, I am using Server Side JavaScript - yes, I am actually using Server Side JavaScript. To complexify things even more, I use Oracle as a backend database (10g). With some crazy XSLT and mutant-like HTML generation, I can build really fancy web forms - yes, I am aware of Rails and other likewise frameworks and I choose the path of horror instead. I have no JQuery or other fancy framework at my disposal, just plain ol' JavaScript that should be supported by the underlying engine called Mozilla Rhino. Yes, it is insane and I love it. So, I have a bunch of tables at my disposal and some of them are filled with associative keys that link to values. As I am a people pleaser, I want to add some nifty user-preference driven solutions. My users have all an unique user_id and this user_id is available during the entire session. My initial idea is to have a user preference table, where I have "three" columns: user_id, feature and pref_string. Using a delimiter, such as : or - (haven't thought about a suitable one yet), I could like store a bunch of preferences as a list and store its elements inside an array using the .split-method (similar like the PHP-explode function). The feature column could be like the table name or some identifier for the "feature" i want to link preferences too. I hate hardcoding objects, especially as I want to be able to back these up and reuse this functionality application-wide. Of course I would love better ideas, just keep in mind I cannot just add a library that easily. These preferences could be like "joined" to the table, so I can query it and use its values. I hope it doesn't sounds too complex, because well.. its basically something really simple I need. Thanks!

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  • Programmtically choosing image conversion format to JPEG or PNG for Silverlight display

    - by Otaku
    I have a project where I need to convert a large number of image types to be displayable in a Silverlight app - TIFF, GIF, WMF, EMF, BMP, DIB, etc. I can do these conversions on the server before hydrating the Silverlight app. However, I'm not sure when I should choose to convert to which format, either JPG or PNG. Is there some kind of standard out there like TIFF should always be a JPEG and GIF should always be a PNG. Or, if a BMP is 24 bit, it should be converted to a JPEG - any lower and it can be a PNG. Or everything is a PNG and why? What I usually see or see in response to this type of question is "Well, if the picture is a photograph, go with JPEG" or "If it has straight lines, PNG is better." Unfortunately, I won't have the luxury of viewing any of the image files at all and would like just a standard way to do this via code, even if that is a zillion if/then statements. Are there any standards or best practices around this subject? P.S. Please don't move to close this subject - it actually has no duplicate on SO because I'm not looking for subjectivity.

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  • jQuery multiple themes on one page

    - by lloydphillips
    This is driving me NUTS! I've followed the post here which just doesn't seem to be working: http://www.filamentgroup.com/lab/using_multiple_jquery_ui_themes_on_a_single_page/ I have a base theme, for examples sake it's the Smoothness theme from the jQuery UI gallery. Then I have a 'red' theme which basically colours the buttons red. Here is the theme I created. So I go to download my theme. Choose Advanced settings, set the scope to 'red' and my theme folder name to 'red' and download. First of all I'm not entirely 100% sure which folder I'm to copy over to my project is it the 'development-bundle\themes' folder (which contains my red folder) or the '\css\red' folder? I've tried both. The post above seems to suggest if I copy my themes folder and link to my theme in the css it'll work when I add a class of 'red' to a wrapper div or element. So I've linked the themes like so in my file: <link type="text/css" href="themes/base/jquery.ui.all.css" rel="stylesheet" /> <link type="text/css" href="themes/red/jquery.ui.all.css" rel="stylesheet" /> The base theme loads and works all honkey doorey but the red theme doesn't. I've got a button styled like so: <input type="submit" id="btn" value="A submit button" class="red" /> I've also tried: <div class="red"> <input type="submit" id="btn" value="A submit button" /> </div> Neither work. When I remove the 'themes/base/jquery.ui.all.css' css file link the button's aren't styled at all. Crazy! I'm pulling my hair out. Where am I going wrong? Surely they should just make it easy enough to download JUST the theme folder and reference the ui.all file.

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  • Gracefully handling screen orientation change during activity start

    - by Steve H
    I'm trying to find a way to properly handle setting up an activity where its orientation is determined from data in the intent that launched it. This is for a game where the user can choose levels, some of which are int portrait orientation and some are landscape orientation. The problem I'm facing is that setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE) doesn't take effect until the activity is fully loaded. This is a problem for me because I do some loading and image processing during startup, which I'd like to only have to do once. Currently, if the user chose a landscape level: the activity starts onCreate(), defaulting to portrait discovers from analysing its launching Intent that it should be in landscape orientation continues regardless all the way to onResume(), loading information and performing other setup tasks at this point setRequestedOrientation kicks in so the application runs through onPause() to onDestroy() it then again starts up from onCreate() and runs to onResume() repeating the setup from earlier Is there a way to avoid that and have it not perform the loading twice? For example, ideally, the activity would know before even onCreate was called whether it should be landscape or portrait depending on some property of the launching intent, but unless I've missed something that isn't possible. I've managed to hack together a way to avoid repeating the loading by checking a boolean before the time-consuming loading steps, but that doesn't seem like the right way of doing it. I imagine I could override onSaveInstanceState, but that would require a lot of additional coding. Is there a simple way to do this? Thanks!

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  • can i know the Thread runnable class attributes in java?

    - by dori naji
    probability this question have been asked before but i cant find anything in my searching mechanism. I am trying to create a multiple threads, in an array list but i want to retrieve them from an arraylist and filter them by the attribute of w1 i used in my code. any ideas ? w1 = new FirstWorker(ProductsList, OrdersList, s); FirstWorkerThread = new Thread(w1); ThreadArrayList.add(FirstWorkerThread); //I know i cant do the code below but i want to do that how ? for(Thread x : ThreadArrayList){ x.ProductsList } this is FirstWorker class import java.lang.String; import java.util.HashMap; /* * To change this template, choose Tools | Templates and open the template in * the editor. */ /** * * @author Dimitris */ public class FirstWorker extends Thread implements Runnable { private OrderList orderlist; private ProductList productlist; private String Worker; boolean Stop; private int speed = 1000; public FirstWorker(ProductList productlist, OrderList orderlist, String Worker) { this.productlist = productlist; this.orderlist = orderlist; this.Worker = Worker; this.Stop = true; } public void run() { if (Stop == true) { try { Thread.sleep(100); } catch (InterruptedException e) { } while (orderlist.returnLengthofOrder() != 0) { if (Thread.interrupted()) { System.out.println("I am in the thread inturrupt"); // We've been interrupted: no more crunching. return; } if (orderlist.getDone() == true) { } else if (orderlist.getDone() == false) { orderlist.setDoneTrue(); orderlist.Purchased(Worker); orderlist.setDoneFalse(); try { Thread.sleep(this.speed); } catch (InterruptedException e) { return; } } } } } public void setWork() { Stop = false; } public void setSpeed(int speed) { this.speed = speed; } }

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  • How to represent and insert into an ordered list in SQL?

    - by Travis
    I want to represent the list "hi", "hello", "goodbye", "good day", "howdy" (with that order), in a SQL table: pk | i | val ------------ 1 | 0 | hi 0 | 2 | hello 2 | 3 | goodbye 3 | 4 | good day 5 | 6 | howdy 'pk' is the primary key column. Disregard its values. 'i' is the "index" that defines that order of the values in the 'val' column. It is only used to establish the order and the values are otherwise unimportant. The problem I'm having is with inserting values into the list while maintaining the order. For example, if I want to insert "hey" and I want it to appear between "hello" and "goodbye", then I have to shift the 'i' values of "goodbye" and "good day" (but preferably not "howdy") to make room for the new entry. So, is there a standard SQL pattern to do the shift operation, but only shift the elements that are necessary? (Note that a simple "UPDATE table SET i=i+1 WHERE i=3" doesn't work, because it violates the uniqueness constraint on 'i', and also it updates the "howdy" row unnecessarily.) Or, is there a better way to represent the ordered list? I suppose you could make 'i' a floating point value and choose values between, but then you have to have a separate rebalancing operation when no such value exists. Or, is there some standard algorithm for generating string values between arbitrary other strings, if I were to make 'i' a varchar? Or should I just represent it as a linked list? I was avoiding that because I'd like to also be able to do a SELECT .. ORDER BY to get all the elements in order.

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  • PayPal IPN "FAIL"

    - by Rob
    Hey all... I'm trying to figure out how to use PayPal's IPN and I've run into a wall. I want a buyer to be forwarded to a success page after making a purchase, and I want that page to show the details of their transaction. I choose IPN instead of the PDT because I also want to do some other behind the scenes stuff with their data. Anyway, here's the code I'm using -- I'm testing in sandbox mode -- but it returns "FAIL" every time. $req = 'cmd=_notify-validate'; foreach ($_POST as $key => $value) { $value = urlencode(stripslashes($value)); $req .= "&$key=$value"; } // post back to PayPal system to validate $header = "POST /cgi-bin/webscr HTTP/1.0\r\n"; $header .= "Content-Type: application/x-www-form-urlencoded\r\n"; $header .= "Content-Length: " . strlen($req) . "\r\n\r\n"; $fp = fsockopen ('www.sandbox.paypal.com', 80, $errno, $errstr, 30); if (!$fp) { // HTTP ERROR } else { fputs ($fp, $header . $req); while (!feof($fp)) { $res = fgets ($fp, 1024); if (strcmp ($res, "VERIFIED") == 0) { // PAYMENT VALIDATED & VERIFIED! echo "Validated!"; } else if (strcmp ($res, "INVALID") == 0) { // PAYMENT INVALID & INVESTIGATE MANUALY! echo "Invalid!"; } } fclose ($fp); }

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  • ASP.Net ListBox selections not working in Panel?

    - by larryq
    Hi everyone, I'm having trouble processing a listbox after selecting some items from it. In my markup, the listbox is contained within an asp:panel and is populated during page load in the codebehind. That part works fine. It's when I select various items and submit that I have trouble. My handler loops through the listbox items but doesn't see any as being selected. I'm not sure why. Here's the markup: <asp:Panel ID="panEdit" runat="server" Height="180px" Width="400px" CssClass="ModalWindow"> <table width="100%"> <asp:label runat = "server">Choose your items</asp:label> <tr> <td> <asp:ListBox ID="lstFundList" runat="server" SelectionMode="Multiple" OnLoad="lstFundList_LoadData"> </asp:ListBox> </td> </tr> </table> <asp:Button ID="btnUpdate" runat="server" Text="Update" OnClick="btnUpdate_OnClick"/> <asp:Button ID="btnCancel" runat="server" Text="Cancel" OnClientClick="$find('ModalPopupExtender1').hide(); return false;" /> </asp:Panel> In my btnUpdate_OnClick handler I can't see any listbox items that are marked as selected. I assume something strange is going on with respect to postback and the panel?

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  • How can I work around WinXP using ports 1025-5000 as ephemeral?

    - by Chris Dolan
    If you create a TCP client socket with port 0 instead of a non-zero port, then the operating system chooses any free ephemeral port for you. Most OSes choose ephemeral ports from the IANA dynamic port range of 49152-65535. However in Windows Server 2003 and earlier (including XP) Microsoft used ports 1025-5000 as the ephemeral range, according to their bind() documentation. I run multiple Java services on the same hardware. On rare occasions, this range collides with well-known ports that I use for other services (e.g. port 4160 for Jini discovery). While rare, this has caused real problems. Is there any easy way to tell Windows or Java to use a different port range for client sockets? Microsoft's docs indicate that I can change the high end of that range via the MaxUserPort TcpIP registry setting, but I see no way to change the low end. Update: I've made some progress on this. It looks like Microsoft has a concept of reserved ports that are exceptions to the ephemeral port range. There's a registry setting that lets you change this permanently and apparently there must be an API to do the same thing because there's a data structure that holds high/low values for reserved port ranges, but I can't find the actual function call anywhere... The registry solution may work, but now I'm fixated on this API.

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  • how to make the user add and delete in android

    - by user3678019
    i have 1 activity .. and in this activity i have 2 web view next to each other , i would like to add , ADD and Delete Button that can add one more web view next to the last web view , and the delete wish will delete any of the web view the user choose . and i want to make the user but it in the order he want like webview 1 first then webview 2 second how can i do this this is mu main.xml <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="test.zezo.test.Main$PlaceholderFragment" > <HorizontalScrollView android:id="@+id/horizontalScrollView2" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_alignParentLeft="true" android:layout_alignParentRight="true" android:layout_alignParentTop="true" > <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="horizontal" > <WebView android:id="@+id/webView1" android:layout_width="350dp" android:layout_height="match_parent" android:layout_alignParentLeft="true" /> <WebView android:id="@+id/webView22" android:layout_width="350dp" android:layout_height="match_parent" android:layout_toRightOf="@+id/webView1" android:layout_alignParentLeft="true" /> </LinearLayout> </HorizontalScrollView> and this is a part of my main.java webView = (WebView) findViewById(R.id.webView1); String url = "http://google.com"; webView.getSettings().setJavaScriptEnabled(true); webView.loadUrl(url); webView.setWebChromeClient(new WebChromeClient()); webView.setWebViewClient(new WebViewClient()); WebView webView22 = (WebView)findViewById(R.id.webView22); webView22.getSettings().setJavaScriptEnabled(true); webView22.loadUrl("google.com); webView22.setWebChromeClient(new WebChromeClient()); webView22.setWebViewClient(new WebViewClient()); so how can i do the ADD and DELETE and re Order Buttons to it and one more thing it should be save so when he reopen the app it will be the same as after he add or delete or re order

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  • maven and unit testing - combining maven surefire plugin AND testNG eclipse plugin

    - by lisak
    Hey, could you please share your way of unit testing in eclipse ? Are you using surefire plugin, m2eclipse & maven, or only testNG eclipse plugin ? Do you combine these alternatives ? I'm using testNG + maven surefire-plugin and I had been using the testNG eclipse plugin a year ago so that I could see the results in testNG view. Then I started using Maven, but when I do "maven test phase" using m2eclipse, there is only console output and surefire reports that I can check in browser and to choose what test suite, test, or test method can be set up only via testng.xml. On the other hand, if you use only surefire plugin and you have some specific settings regarding classpath etc., that you rely on, then running tests via testNG eclipse plugin doesn't have to be compatible with your code. Using surefire plugin, the classpath is different - target/test-classes and target/classes - than using testNG plugin, that is using the project classpath. How do you go about what I was just talking about? Is it possible to synchronize "maven test" using m2eclipse and surefire plugin WITH testNG eclipse plugin and view ? EDITED: I'm also wondering, why the Maven project ("Java build path") output folder is target/classes for src/main and src/test whereas surefire plugin makes two locations target/test-classes and target/classes Thank you very much for your your opinions.

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  • Paramaterising SQL in SSIS

    - by Anonymouslemming
    Hi all, I'm trying to paramaterize some queries in SSIS. After some reading, it sounds like my best option is to create one variable that contains my base sql, another that contains my criteria and a final variable that is evaluated as an expression that includes both of these. I want to end up with an SQL query that is effectively UPDATE mytable set something='bar' where something_else='foo' So my first two variables have the scope of my package and are as follows: Name: BaseSQL Data Type: String Value: UPDATE mytable set something = 'bar' where something_else = Name: MyVariable Data Type: String Value: foo My third variable has a scope of the data flow task where I want to use this SQL and is as follows: Name: SQLQuery Data Type: String Value: @[User::BaseSQL] + "'" + @[User::MyVariable] + "'" EvaluateAsExpression: True In the OLE DB Source, I then choose my connection and 'SQL command from variable' and select User::SQLQuery from the dropdown box. The Variable Value window then displays the following: @[User::BaseSQL] + "'" + @[User::MyVariable] + "'" This is as desired, and would provide the output I want from my DB. The variable name dropdown also contains User::BaseSQL and User::MyVariable so I believe that my namespaces are correct. However, when I then click preview, I get the following error when configuring an OLE DB Source (using SQL command from variable): TITLE: Microsoft Visual Studio Error at Set runtime in DB [Set runtime in myDb DB [1]]: SSIS Error Code DTS_E_OLEDBERROR. An OLE DB error has occurred. Error code: 0x80040E14. An OLE DB record is available. Source: "Microsoft SQL Server Native Client 10.0" Hresult: 0x80040E14 Description: "Statement(s) could not be prepared.". An OLE DB record is available. Source: "Microsoft SQL Server Native Client 10.0" Hresult: 0x80040E14 Description: "Must declare the scalar variable "@".". (Microsoft Visual Studio) Can anyone advise what I'm missing or how I can resolve this please ? Thanks in advance!

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  • Bind WCF webservice to specific network interface / IP

    - by Markus
    On a machine with multiple network cards I need to bind a WCF webservice to a specific network interface. It seems that the default is to bind on all network interfaces. The machine has two network adapters with the IPs 192.168.0.10 and 192.168.0.11. I have an Apache running that binds on 192.168.0.10:80 and need to run the webservice on 192.168.0.11:80. (Due to external circumstances I cannot choose another port.) I tried the following: string endpoint = "http://192.168.0.11:80/SOAP"; ServiceHost = new ServiceHost(typeof(TService), new Uri(endpoint)); ServiceHost.AddServiceEndpoint(typeof(TContract), Binding, ""); // or: ServiceHost.AddServiceEndpoint(typeof(TContract), Binding, endpoint); But it doesn't work; netstat -ano -p tcp always shows the webservice listening on 0.0.0.0:80, which is all interfaces (if I got that correct). When I start Apache first, it correctly binds to the other interface, which in turn prevents the WCF service to bind to "all". Any ideas?

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  • Running mysql query using node blocks the whole process and then timesout

    - by lobengula3rd
    I have a node javascript that uses mysql npm (Felix). I have a procedure stored in my DB which I call when the user selects an option to kind of create its own instance of the program. The user chooses for how long he wants that data to be initialized for him. This is suppsoed to be between 1 and 2 years. So if he choose 1 year this query will insert around 20,000 rows into 1 table. If I run this query and a local DB this takes around 30 seconds (I suppose it is reasonable because its a big query which should be done only once in 1 or 2 years so its ok). For some reason my node script freezes as if it can't handle any more calls from other users. The even worse problem is that after like 2 minutes my client ui gets like an error from the server. At this point not all the data that was supposed to enter the DB is entered. After waiting like another minute all the data finally gets to the DB and only then it will accept new requests. This is my connection: this.connection = mysql.createConnection({ host : '********rds.amazonaws.com', user : 'admin', password : '******', database : '*****' }); and this is my query function: this.createCourts = function (req, res, next){ connection.query('CALL filldates("' + req.body['startDate'] + '","' + req.body['endDate'] + '","' + req.body['numOfCourts'] + '","' + req.body['duration'] + '","' + req.body['sundayOpen'] + '","' + req.body['mondayOpen'] + '","' + req.body['tuesdayOpen'] + '","' + req.body['wednesdayOpen'] + '","' + req.body['thursdayOpen'] + '","' + req.body['fridayOpen'] + '","' + req.body['saturdayOpen'] + '","' + req.body['sundayClose'] + '","' + req.body['mondayClose'] + '","' + req.body['tuesdayClose'] + '","' + req.body['wednesdayClose'] + '","' + req.body['thursdayClose'] + '","' + req.body['fridayClose'] + '","' + req.body['saturdayClose'] + '");', function(err){ if (err){ console.log(err); } else return res.send(200); }); }; what am i missing here? as i understand connection.query should by async so why is it actually blocking my node script? thanks.

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  • Web development: Haskell or Scheme

    - by Robert E. Lester
    I would like to to choose one of these languages for building web applications. I'm not interested in framework per say, but have the following needs: Rapid development. Easy to scale. Strong community for the web. Quick and easy to deploy. I'm very familiar with Haskell, and have some familiarity with scheme (in particular PLT). Scheme appeals to me as good candidate for web development due to it's simple syntax which is homogenous across libraries. I state this despite my subjective opinion that Haskell is a 'cleaner' language. Haskell web apps seem to require learning and building a patchwork of different combinator libraries. On the plus side, I realise this can be quite expressive, although I'd prefer to eliminate impedance mismatches where possible. While scheme-plt looks to be a good fit, I can find but one example of it being used in the "real world". Haskell doesn't seem to fair too much better here, but there seems to be a bigger community behind the web side. Please help me make up my mind. For the most part I'm interested in real-world use cases.

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  • Extension methods for encapsulation and reusability

    - by tzaman
    In C++ programming, it's generally considered good practice to "prefer non-member non-friend functions" instead of instance methods. This has been recommended by Scott Meyers in this classic Dr. Dobbs article, and repeated by Herb Sutter and Andrei Alexandrescu in C++ Coding Standards (item 44); the general argument being that if a function can do its job solely by relying on the public interface exposed by the class, it actually increases encapsulation to have it be external. While this confuses the "packaging" of the class to some extent, the benefits are generally considered worth it. Now, ever since I've started programming in C#, I've had a feeling that here is the ultimate expression of the concept that they're trying to achieve with "non-member, non-friend functions that are part of a class interface". C# adds two crucial components to the mix - the first being interfaces, and the second extension methods: Interfaces allow a class to formally specify their public contract, the methods and properties that they're exposing to the world. Any other class can choose to implement the same interface and fulfill that same contract. Extension methods can be defined on an interface, providing any functionality that can be implemented via the interface to all implementers automatically. And best of all, because of the "instance syntax" sugar and IDE support, they can be called the same way as any other instance method, eliminating the cognitive overhead! So you get the encapsulation benefits of "non-member, non-friend" functions with the convenience of members. Seems like the best of both worlds to me; the .NET library itself providing a shining example in LINQ. However, everywhere I look I see people warning against extension method overuse; even the MSDN page itself states: In general, we recommend that you implement extension methods sparingly and only when you have to. So what's the verdict? Are extension methods the acme of encapsulation and code reuse, or am I just deluding myself?

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  • ASP .NET confusion - server controls

    - by Brandi
    I have read through the information in this question: http://stackoverflow.com/questions/22084/asp-net-aspxxx-controls-versus-standard-html but am still rather confused. The situation was I was asked to do a web project where I made a wizard. When I was done with the project everyone asked why I had used an <asp:Wizard...>. I thought this was what was being asked for, but apparently not, so after this I was led to believe that server controls were just prototyping tools. However, the next project I did my DB queries through C# code-behind and loaded the results via html. I was then asked why I had not used a gridview and a dataset. Does anyone have a list of pros and cons why they would choose to use specific html controls over specific server controls and why? I guess I'm looking for a list... what server controls are okay to use and why? EDIT: I guess this question is open ended, so I'll clarify a few more specific questions... Is it okay to use very simple controls such as asp:Label or do these just end up wasting space? It seems like it would be difficult to access html in the code behind otherwise. Are there a few controls that should just never be used? Does anyone have a good resource that will show me pros and cons of each control?

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  • In Java it seems Public constructors are always a bad coding practice

    - by Adam Gent
    This maybe a controversial question and may not be suited for this forum (so I will not be insulted if you choose to close this question). It seems given the current capabilities of Java there is no reason to make constructors public ... ever. Friendly, private, protected are OK but public no. It seems that its almost always a better idea to provide a public static method for creating objects. Every Java Bean serialization technology (JAXB, Jackson, Spring etc...) can call a protected or private no-arg constructor. My questions are: I have never seen this practice decreed or written down anywhere? Maybe Bloch mentions it but I don't own is book. Is there a use case other than perhaps not being super DRY that I missed? EDIT: I explain why static methods are better. .1. For one you get better type inference. For example See Guava's http://code.google.com/p/guava-libraries/wiki/CollectionUtilitiesExplained .2. As a designer of the class you can later change what is returned with a static method. .3. Dealing with constructor inheritance is painful especially if you have to pre-calculate something.

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  • How to get Facebook Login Button To Display "Logout"

    - by Will Merydith
    I apologize ahead of time if this is clearly documented somewhere on the FB developer site - but I can't find it (so please link me if appropriate). I've implemented the FB login button on a website using GAE + Python. Here is the HTML: <fb:login-button></fb:login-button> <div id="fb-root"></div> <script src="http://connect.facebook.net/en_US/all.js"></script> <script> FB.init({appId: 'ad16a806fc10bef5d30881322e73be68', status: true, cookie: true, xfbml: true}); FB.Event.subscribe('auth.sessionChange', function(response) { if (response.session) { // A user has logged in, and a new cookie has been saved } else { // The user has logged out, and the cookie has been cleared } }); </script> Currently the behavior is - if I click on the "login" button, I am asked to allow the application access to FB. Which I then choose, "OK". But then the login button is still showing "login" and not "logout". How do I implement that? On the server or client side?

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  • how to conditional display a control in asp wizard based on the radiobutton click in a particular st

    - by Pramod
    Hi, I've been stuck with this problem where there are 3 steps in an asp wizard control. The first step has a radiobutton (yes and no) and based on the radio button input chosen by the user, i would need to hide or show a label in the second wizardstep. Example: Step 1: Choose 1 among the two options: Yes No (radStep1) Step 2: if the radiobutton option in the previous step was yes.. then display a label(lblStep2) in this step.. Else hide the label. I've been handling this through the jquery as i want the functionality in the aspx page itself... The jquery code goes like this... $("#<%=radStep1.ClientID %> input").click(function() { if($("#<%= radStep1.ClientID %> input").index(this) == 0) { $("#<%=lblStep2.ClientID %>").show(); } else if($("#<%= radStep1.ClientID %> input").index(this) == 1) { $("#<%=lblStep2.ClientID %>").hide(); } However, in both the cases, the label is getting displayed.. Could you please help me out if there is anything that i'm missing? I'm guessing that the label is getting hidden at first and then getting shown again once i click on the next button... Thanks a ton in advance....

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  • Batch Image compression tool for optimizing thousands of images

    - by Daniel Magliola
    Hi all, I'm maintaining a site that has thousands of images that have not been compressed nearly enough. The homepage weighs in at 1.5 Mb currently, and it could easily be way less that half that. I'm looking for some kind of tool that'll take a folder full of JPG pictures and will recompress them to their "optimal" compression value. Obviously, "optimal lossy compression setting" is an oxymoron, but I'm thinking maybe a tool that'll try different levels and compare the outputs to the input, and choose a "sweet spot" between size and destruction? Or even try whether PNG is a better option, many times it is, for "drawing" type stuff. Does anyone of you know any such tool? I'd have lots of fun coding one, but I bet someone already did and will save me 2 days. Alternatively, of course, anything that'll take all pictures in a folder and recompress them with a fixed quality level (say, 40) will also work, it'll just not make my inner nerd as happy, but it'll solve my problem just fine. (Ideally something that can run on Windows, ideally from the command line) Thank you!

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  • Connecting to database on web host in Visual Studio

    - by Anders Svensson
    I have a web site developed locally with a local Sql Server database. I also have a web host that provides one Sql Server database for my site. Now I want to deploy the application, and I would like to be able to manage the remote database from the Server Explorer in Visual Studio. I have the connection string used in the application, which works fine for adding, say, a datasource to a control etc. But I don't know if there's any way to use it to connect the database inside the Server Explorer so that I can add tables etc. I have read that you're supposed to be able to this instead of using the Sql Server Management Studio, but I have'nt read anything about how to connect to the remote database in it. What I have tried so far is this: I have selected Add database in Server Explorer. This brings up first a dialog where I choose Sql Server. And then I get a dialog where I can set Server name (which I tried using the ip address in the connection string below), and Authentication (where I chose Sql Server Authentication, with the user id and password from below). But when I test the connection it fails. Here's the connection string, which works fine when used for datasources in the application (obviously with different user name and password): Any help appreciated!

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