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  • How to stop page refresh when hit enter button from rich:inputNumberSpinner field?

    - by eswaramoorthy-nec
    Hi, I use rich:inputNumberSpinner tag. The problem is : I set cursor focus to inside of rich:inputNumberSpinner field, then i hit the enter button from my keyboard, that time page will be automatically refresh. But i don't need page refresh when i hit the enter button from my keyboard. The code : spinnerTagTest.jsp <%@page contentType="text/html" pageEncoding="UTF-8"%> <%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" %> <%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" %> <%@ taglib uri="http://richfaces.org/a4j" prefix="a4j" %> <%@ taglib uri="http://richfaces.org/rich" prefix="rich"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <f:view> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Spinner Tag Test</title> </head> <body> <h:form id="SpinnerForm"> <rich:panel id="SpinnerPanel"> <h:outputText value="Input Spinner Tag : "/> <rich:inputNumberSpinner id="spinnerField" value="" maxValue="23" inputSize="2"/> </rich:panel> </h:form> </body> I also use rich:hotKey for that inputNumberSpinner field. But Page refreshed. <rich:hotKey key="return" selector="#spinnerField" handler="event.stopPropagation();event.preventDefault(); return false;"/> And i check anotherway using javasccript, but page refreshed. The specific tag and javascript is : <rich:inputNumberSpinner id="spinnerField" value="" maxValue="23" inputSize="2" oninputkeypress="return stopPageRefresh();"/> <script type="text/javascript"> function stopPageRefresh() { return false; } </script> Here i use one alert message inside of stopPageRefresh(). But i hit enter button, first page refreshing and then alert message displayed. Help me about this. Thanks in advance.

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  • Issues loading Jquery (Galleria) script from inside an i-frame (beginner javascript?)

    - by 103188530284789248582
    Hello, first of all - I'm not entirely new to javascript, but am not fluent in it as I am with html and css, and am especially new to jQuery... so please excuse me if this questions seems easy or obvious, but after days of google I still have no solution to the problem... using jQuery 1.4.2.min, jQuery-ui-1.8.1 .... the site in question: http://homecapture.ca/sets/project_index.html The scenario: I have a tabbed menu generated from an unordered list, when a menu item is clicked it reveals an iframe which links to the page containing an image gallery. I am using jQuery UI tabs for the tabbed menu, and the galleries to which I'm linking are jQuery Galleria pages, automatically generated with Jalbum. The problem: The galleria plug-in only works normally from inside of the containing iframe in Chrome, has inconsistent behaviour in IE8 (seems to work in my local copy, but won't load properly online), and is not loaded properly in Firefox. Instead of displaying a thumbnail area and the first large image, the Galleria page shows the first thumbnail only, then when it is clicked the image it links to, but if you right-click and go Back, the iframe content shows up as a properly rendered Galleria page. Jalbum generates more script in the < head of the page in addition to linking to jquery and the galleria plug-in. All of it seems to be in charge of the gallery navigation , and I have relocated it to the < body of the page, in an effort to make it load after the parent page scripts, and together with the gallery content. At this point I am not sure what else I could do to solve the problem, without digging around in all or some of the library and pluging .js files (which I am not knowledgeable enough to do without some pointers). Has anyone dealt with a similar issue? I'm seeing some solutions for manipulating iframe content from a parent page with jQuery on here, is that what I should be researching instead? Thanks in advance for all the help! ps. I tried posting some code, but it seems I do not have enough 'reputation' for things to work right on here either :)

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  • Want to show <embed> and <object> tags from YUI editor as a text rather then a video.

    - by user208678
    I am using YUI rich text editor on my website (php/mysql), so that a user may enter textual matter/articles through it. But if a user copies and paste some embed code in the textarea, from any video sites like youtube, it should get saved as a text block and not as a playing video when showing the text content on the browser. Now YUI automatically converts the characters into html entities which ever is needed. Please note that if I put a new line in the yui editor (by pressing "Enter" key), it will be converted into a "<br>" tag in the background and this will not get html entity encoded when passing the value to my backend PHP script. But If I copy and paste any embed tag or for that reason any valid html tags in the textarea, it will be html entity encoded by YUI. Now to support UTF-8 characters, I am using a function (DBVarConv) in my php script before saving it into my database. The code for the function is given below function DBVarConv($var,$isEncoded = false) { if($isEncoded) return addslashes(htmlentities($var, ENT_QUOTES, 'UTF-8', false)); else return htmlentities ($var, ENT_QUOTES, 'UTF-8', false); } $myeditorData = DBVarConv($myeditorData, true); // Save $myeditorData in database. While showing the data in the browser, I am using another function called "smart_html_entity_decode". The code is given below. function smart_html_entity_decode($text, $isAddslashesUsed = false) { if($isAddslashesUsed) $tmp = stripslashes(html_entity_decode($text, ENT_QUOTES, 'UTF-8')); else $tmp = html_entity_decode($text, ENT_QUOTES, 'UTF-8'); if ($tmp == $text) return $tmp; return smart_html_entity_decode($tmp, $isAddslashesUsed); } // Get $myData from database $myData=smart_html_entity_decode($myData, true); echo $myData; The problem is that in doing so, it is also decoding the embed and object tags from their html encoded entities and as a result my obejct tags are shown as a video and not as a simple text. Try using the text editor at tumblr.com. If you paste an embed code in the editor, it will be shown as a text block not as a video. I am trying to build the same functionality on my website with UTF-8 support. Any help will be highly appreciated.

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  • how to implement a "soft barrier" in multithreaded c++

    - by Jason
    I have some multithreaded c++ code with the following structure: do_thread_specific_work(); update_shared_variables(); //checkpoint A do_thread_specific_work_not_modifying_shared_variables(); //checkpoint B do_thread_specific_work_requiring_all_threads_have_updated_shared_variables(); What follows checkpoint B is work that could have started if all threads have reached only checkpoint A, hence my notion of a "soft barrier". Typically multithreading libraries only provide "hard barriers" in which all threads must reach some point before any can continue. Obviously a hard barrier could be used at checkpoint B. Using a soft barrier can lead to better execution time, especially since the work between checkpoints A and B may not be load-balanced between the threads (i.e. 1 slow thread who has reached checkpoint A but not B could be causing all the others to wait at the barrier just before checkpoint B). I've tried using atomics to synchronize things and I know with 100% certainty that is it NOT guaranteed to work. For example using openmp syntax, before the parallel section start with: shared_thread_counter = num_threads; //known at compile time #pragma omp flush Then at checkpoint A: #pragma omp atomic shared_thread_counter--; Then at checkpoint B (using polling): #pragma omp flush while (shared_thread_counter > 0) { usleep(1); //can be removed, but better to limit memory bandwidth #pragma omp flush } I've designed some experiments in which I use an atomic to indicate that some operation before it is finished. The experiment would work with 2 threads most of the time but consistently fail when I have lots of threads (like 20 or 30). I suspect this is because of the caching structure of modern CPUs. Even if one thread updates some other value before doing the atomic decrement, it is not guaranteed to be read by another thread in that order. Consider the case when the other value is a cache miss and the atomic decrement is a cache hit. So back to my question, how to CORRECTLY implement this "soft barrier"? Is there any built-in feature that guarantees such functionality? I'd prefer openmp but I'm familiar with most of the other common multithreading libraries. As a workaround right now, I'm using a hard barrier at checkpoint B and I've restructured my code to make the work between checkpoint A and B automatically load-balancing between the threads (which has been rather difficult at times). Thanks for any advice/insight :)

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  • Escaping Code for Different Shells

    - by Jon Purdy
    Question: What characters do I need to escape in a user-entered string to securely pass it into shells on Windows and Unix? What shell differences and version differences should be taken into account? Can I use printf "%q" somehow, and is that reliable across shells? Backstory (a.k.a. Shameless Self-Promotion): I made a little DSL, the Vision Web Template Language, which allows the user to create templates for X(HT)ML documents and fragments, then automatically fill them in with content. It's designed to separate template logic from dynamic content generation, in the same way that CSS is used to separate markup from presentation. In order to generate dynamic content, a Vision script must defer to a program written in a language that can handle the generation logic, such as Perl or Python. (Aside: using PHP is also possible, but Vision is intended to solve some of the very problems that PHP perpetuates.) In order to do this, the script makes use of the @system directive, which executes a shell command and expands to its output. (Platform-specific generation can be handled using @unix or @windows, which only expand on the proper platform.) The problem is obvious, I should think: test.htm: <!-- ... --> <form action="login.vis" method="POST"> <input type="text" name="USERNAME"/> <input type="password" name="PASSWORD"/> </form> <!-- ... --> login.vis: #!/usr/bin/vision # Think USERNAME = ";rm -f;" @system './login.pl' { USERNAME; PASSWORD } One way to safeguard against this kind of attack is to set proper permissions on scripts and directories, but Web developers may not always set things up correctly, and the naive developer should get just as much security as the experienced one. The solution, logically, is to include a @quote directive that produces a properly escaped string for the current platform. @system './login.pl' { @quote : USERNAME; @quote : PASSWORD } But what should @quote actually do? It needs to be both cross-platform and secure, and I don't want to create terrible problems with a naive implementation. Any thoughts?

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  • Adding rows with linq trouble with reference table

    - by Laurence Burke
    I am adding a new address and I know the structure as AddressID = PK and all other entities are non nullable. Now on insert of a new row the addrID Pk is autogened and I am wondering if I would have to get that to create a new row in the referencing table EmployeeAddress or does that automatically get generated also. also I want to be able to repopulate the dropdownlist that lists the current employee's addresses with the newly created address. static uint _curEmpID; protected void btnAdd_Click(object sender, EventArgs e) { if (txtZip.Text != "" && txtAdd1.Text != "" && txtCity.Text != "") { TestDataClassDataContext dc = new TestDataClassDataContext(); Address addr = new Address() { AddressLine1 = txtAdd1.Text, AddressLine2 = txtAdd2.Text, City = txtCity.Text, PostalCode = txtZip.Text, StateProvinceID = Convert.ToInt32(ddlState.SelectedValue) }; dc.Addresses.InsertOnSubmit(addr); lblSuccess.Visible = true; lblErrMsg.Visible = false; dc.SubmitChanges(); // // TODO: insert new row in EmployeeAddress to reference CurEmp to newly created address // SetAddrList(); } else { lblErrMsg.Text = "Invalid Input"; lblErrMsg.Visible = true; } } protected void ddlAddList_SelectedIndexChanged(object sender, EventArgs e) { lblErrMsg.Visible = false; lblSuccess.Visible = false; TestDataClassDataContext dc = new TestDataClassDataContext(); dc.ObjectTrackingEnabled = false; if (ddlAddList.SelectedValue != "-1") { var addr = (from a in dc.Addresses where a.AddressID == Convert.ToInt32(ddlAddList.SelectedValue) select a).FirstOrDefault(); txtAdd1.Text = addr.AddressLine1; txtAdd2.Text = addr.AddressLine2; txtCity.Text = addr.City; txtZip.Text = addr.PostalCode; ddlState.SelectedValue = addr.StateProvinceID.ToString(); btnSubmit.Visible = true; btnAdd.Visible = false; } else { txtAdd1.Text = ""; txtAdd2.Text = ""; txtCity.Text = ""; txtZip.Text = ""; btnAdd.Visible = true; btnSubmit.Visible = false; } } protected void SetAddrList() { TestDataClassDataContext dc = new TestDataClassDataContext(); dc.ObjectTrackingEnabled = false; var addList = from addr in dc.Addresses from eaddr in dc.EmployeeAddresses where eaddr.EmployeeID == _curEmpID && addr.AddressID == eaddr.AddressID select new { AddValue = addr.AddressID, AddText = addr.AddressID, }; ddlAddList.DataSource = addList; ddlAddList.DataValueField = "AddValue"; ddlAddList.DataTextField = "AddText"; ddlAddList.DataBind(); ddlAddList.Items.Add(new ListItem("<Add Address>", "-1")); } OK I am hoping that I did not include too much code. I would really appreciate any other comments about I could otherwise improve this code in any other ways also.

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  • How do I change a child's parent in NHibernate when cascade is delete-all-orphan?

    - by Daniel T.
    I have two entities in a bi-directional one-to-many relationship: public class Storage { public IList<Box> Boxes { get; set; } } public class Box { public Storage CurrentStorage { get; set; } } And the mapping: <class name="Storage"> <bag name="Boxes" cascade="all-delete-orphan" inverse="true"> <key column="Storage_Id" /> <one-to-many class="Box" /> </bag> </class> <class name="Box"> <many-to-one name="CurrentStorage" column="Storage_Id" /> </class> A Storage can have many Boxes, but a Box can only belong to one Storage. I have them mapped so that the one-to-many has a cascade of all-delete-orphan. My problem arises when I try to change a Box's Storage. Assuming I already ran this code: var storage1 = new Storage(); var storage2 = new Storage(); storage1.Boxes.Add(new Box()); Session.Create(storage1); Session.Create(storage2); The following code will give me an exception: // get the first and only box in the DB var existingBox = Database.GetBox().First(); // remove the box from storage1 existingBox.CurrentStorage.Boxes.Remove(existingBox); // add the box to storage2 after it's been removed from storage1 var storage2 = Database.GetStorage().Second(); storage2.Boxes.Add(existingBox); Session.Flush(); // commit changes to DB I get the following exception: NHibernate.ObjectDeletedException : deleted object would be re-saved by cascade (remove deleted object from associations) This exception occurs because I have the cascade set to all-delete-orphan. The first Storage detected that I removed the Box from its collection and marks it for deletion. However, when I added it to the second Storage (in the same session), it attempts to save the box again and the ObjectDeletedException is thrown. My question is, how do I get the Box to change its parent Storage without encountering this exception? I know one possible solution is to change the cascade to just all, but then I lose the ability to have NHibernate automatically delete a Box by simply removing it from a Storage and not re-associating it with another one. Or is this the only way to do it and I have to manually call Session.Delete on the box in order to remove it?

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  • How to play small sound file continuously in Silverlight?

    - by ash
    Hello, I have two questions regarding Silverlight's SoundPlay action and properties. My scenario is like: I have two story board: The first story board has an image and a sound file; when the silverlight application gets loaded, the sound starts to play automatically, but if someone clicks the image, the sound file will stop and the second storyboard will start with a new sound file. 1) My first question is how to stop the first sound file of first story board when the second story board starts with the second sound file. 2) My second question is how to play a sound file continuously; for example, in Silverlight we can play a story board continuously with RepeatBehavior="Forever"; but I cannot find a way to play my 10 second sound file forever or continuously. Note: I have attached a small XAML file to show what I am talking about; I am also stating that if instead of an image file, if there were a button, then I can stop the first music file after I click the button and start my second story board with a new sound file, but I would like to use image file instead of a button. Is it possible? If it is, how to do it? Therefore, please answer my following two questions or give big hint or website tutorial links on 1) How to stop the first sound file of first story board when the second story board starts with the second sound file ( When the clickable element is an image instead of a button) 2) How to play a 10 second sound file continuously? ............Code Snippet...................... XAML ............ <Grid x:Name="LayoutRoot" Background="Red"> <Button HorizontalAlignment="Left" Margin="212,0,0,111" VerticalAlignment="Bottom" Width="75" Content="Button" Click="onClick"/> <MediaElement x:Name="sound2_mp3" Height="0" HorizontalAlignment="Left" Margin="105,230,0,0" VerticalAlignment="Top" Width="0" Source="/sound2.mp3" Stretch="Fill"/> <MediaElement x:Name="sound1_mp1" Height="0" HorizontalAlignment="Left" Margin="190,164,0,0" VerticalAlignment="Top" Width="0" Source="/sound1.mp3" Stretch="Fill" AutoPlay="False"/> </Grid> ..................................................................................................................................................................................................................... using System; using System.Windows; using System.Windows.Controls; using System.Windows.Documents; using System.Windows.Ink; using System.Windows.Input; using System.Windows.Media; using System.Windows.Media.Animation; using System.Windows.Shapes; namespace testPrj { public partial class MainPage : UserControl { public MainPage() { // Required to initialize variables InitializeComponent(); } private void onClick(object sender, System.Windows.RoutedEventArgs e) { Storyboard1.Stop(); sound2_mp3.Stop(); sound1_mp1.Play(); } } } ...................................................................................................

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  • Spring ROO issue with UrlRewrite in STS (eclipse)

    - by user224270
    I'm having trouble figuring out how to solve this issue. I have a file called: "urlrewrite.xml" which was automatically generated by spring ROO after running the "controller" command in ROO Shell. However, I still get the following error: "Referenced file contains errors (http://tuckey.org/res/dtds/urlrewrite3.0.dtd). For more information, right click on the message in the Problems View and select "Show Details..." Here's the content of the urlrewrite.xml file: <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE urlrewrite PUBLIC "-//tuckey.org//DTD UrlRewrite 3.0//EN" "http://tuckey.org/res/dtds/urlrewrite3.0.dtd"> <urlrewrite default-match-type="wildcard"> <rule> <from>/resources/**</from> <to last="true">/resources/$1</to> </rule> <rule> <from>/static/WEB-INF/**</from> <set type="status">403</set> <to last="true">/static/WEB-INF/$1</to> </rule> <rule> <from>/static/**</from> <to last="true">/$1</to> </rule> <rule> <from>/</from> <to last="true">/app/index</to> </rule> <rule> <from>/app/**</from> <to last="true">/app/$1</to> </rule> <rule> <from>/**</from> <to>/app/$1</to> </rule> <outbound-rule> <from>/app/**</from> <to>/$1</to> </outbound-rule> </urlrewrite> Any thoughts on how to get rid of this error?

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  • How to generate and encode (for use in GA), random, strict, binary rooted trees with N leaves?

    - by Peter Simon
    First, I am an engineer, not a computer scientist, so I apologize in advance for any misuse of nomenclature and general ignorance of CS background. Here is the motivational background for my question: I am contemplating writing a genetic algorithm optimizer to aid in designing a power divider network (also called a beam forming network, or BFN for short). The BFN is intended to distribute power to each of N radiating elements in an array of antennas. The fraction of the total input power to be delivered to each radiating element has been specified. Topologically speaking, a BFN is a strictly binary, rooted tree. Each of the (N-1) interior nodes of the tree represents the input port of an unequal, binary power splitter. The N leaves of the tree are the power divider outputs. Given a particular power divider topology, one is still free to map the power divider outputs to the array inputs in an arbitrary order. There are N! such permutations of the outputs. There are several considerations in choosing the desired ordering: 1) The power ratio for each binary coupler should be within a specified range of values. 2) The ordering should be chosen to simplify the mechanical routing of the transmission lines connecting the power divider. The number of ouputs N of the BFN may range from, say, 6 to 22. I have already written a genetic algorithm optimizer that, given a particular BFN topology and desired array input power distribution, will search through the N! permutations of the BFN outputs to generate a design with compliant power ratios and good mechanical routing. I would now like to generalize my program to automatically generate and search through the space of possible BFN topologies. As I understand it, for N outputs (leaves of the binary tree), there are $C_{N-1}$ different topologies that can be constructed, where $C_N$ is the Catalan number. I would like to know how to encode an arbitrary tree having N leaves in a way that is consistent with a chromosomal description for use in a genetic algorithm. Also associated with this is the need to generate random instances for filling the initial population, and to implement crossover and mutations operators for this type of chromosome. Any suggestions will be welcome. Please minimize the amount of CS lingo in your reply, since I am not likely to be acquainted with it. Thanks in advance, Peter

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  • Why do some questions get closed for no reason? [closed]

    - by IVlad
    Recently there was a question asking about generating all subsets of a set using a stack and a queue, which was closed (and now deleted it seems) as not a real question for no good reason, since it didn't fit into any of these conditions: It's difficult to tell what is being asked here. No, it was clear what was being asked. This question is ambiguous, vague, incomplete, or rhetorical and cannot be reasonably answered in its current form. Not ambiguous, not vague, not incomplete, definitely not rhetorical and could easily be answered if one knew the solution. Now, the exact same thing has happened with this question: http://stackoverflow.com/questions/2791982/a-shortest-path-problem-with-superheroes-and-intergalactic-journeys/2793746#2793746 I am interested in hearing a logical argument for why that question is either ambiguous, vague, incomplete, rhetorical or cannot reasonably be answered in its current form. It seems that (the same bunch of) people like to close questions that they think are homework questions, especially when they think people want to be served the solution on a platter, which is also not the case: Any suggestions or ideas of how this problem might be solved would be most welcomed. Most of the time the people asking these questions are very reasonable and appreciate even the most vague idea, yet their question is closed. Let's go further and assume that it IS a homework problem. So what? When I registered here I didn't see any rule that said not to post homework problems, nor do I see such a rule now. What is wrong with posting homework problems that makes people hunt them down with a passion to close them without even reading the entire question body? This site is full of questions asked by people who get paid to know the things they are asking, yet their questions are considered fine. How is solving someone's homework problem worse? In some places (like where I live), computer science is a mandatory high school subject, and not everyone is interested in it. How is helping at least those people worse than doing someone's JOB? Not answering homework questions is fine and it's everyone's choice, but I consider closing them to be an act of power abuse, selfishness, and an insult to the fellow community members who are also interested in a solution or want feedback on their proposed solution. So my questions are: - Why do questions like the above get closed for reasons that do not apply? Why do you close them? Why don't you? - Why doesn't a vote to reopen a question reopen it automatically? Needing 5 votes for a reopen takes too long, and it's not fair because one reopen vote basically cancels out a close vote, making it 4 close votes (or 5 to 1, which is the same as only 4 people wanting to close the question), which isn't enough to close the question. I think a question should only be closed when CloseVotes - ReopenVotes >= 5. I'm hoping this will stay up, but I realize it probably won't. In either case, I think this is worth saying and discussing, since it IS community-related.

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  • Sockets, Threads and Services in android, how to make them work together ?

    - by Spredzy
    Hi all, I am facing a probleme with threads and sockets I cant figure it out, if someone can help me please i would really appreciate. There are the facts : I have a service class NetworkService, inside this class I have a Socket attribute. I would like it be at the state of connected for the whole lifecycle of the service. To connect the socket I do it in a thread, so if the server has to timeout, it would not block my UI thread. Problem is, into the thread where I connect my socket everything is fine, it is connected and I can talk to my server, once this thread is over and I try to reuse the socket, in another thread, I have the error message Socket is not connected. Questions are : - Is the socket automatically disconnected at the end of the thread? - Is their anyway we can pass back a value from a called thread to the caller ? Thanks a lot, Here is my code public class NetworkService extends Service { private Socket mSocket = new Socket(); private void _connectSocket(String addr, int port) { Runnable connect = new connectSocket(this.mSocket, addr, port); new Thread(connect).start(); } private void _authentification() { Runnable auth = new authentification(); new Thread(auth).start(); } private INetwork.Stub mBinder = new INetwork.Stub() { @Override public int doConnect(String addr, int port) throws RemoteException { _connectSocket(addr, port); _authentification(); return 0; } }; class connectSocket implements Runnable { String addrSocket; int portSocket; int TIMEOUT=5000; public connectSocket(String addr, int port) { addrSocket = addr; portSocket = port; } @Override public void run() { SocketAddress socketAddress = new InetSocketAddress(addrSocket, portSocket); try { mSocket.connect(socketAddress, TIMEOUT); PrintWriter out = new PrintWriter(mSocket.getOutputStream(), true); out.println("test42"); Log.i("connectSocket()", "Connection Succesful"); } catch (IOException e) { Log.e("connectSocket()", e.getMessage()); e.printStackTrace(); } } } class authentification implements Runnable { private String constructFirstConnectQuery() { String query = "toto"; return query; } @Override public void run() { BufferedReader in; PrintWriter out; String line = ""; try { in = new BufferedReader(new InputStreamReader(mSocket.getInputStream())); out = new PrintWriter(mSocket.getOutputStream(), true); out.println(constructFirstConnectQuery()); while (mSocket.isConnected()) { line = in.readLine(); Log.e("LINE", "[Current]- " + line); } } catch (IOException e) {e.printStackTrace();} } }

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  • Repeating fields in similar database tables

    - by user1738833
    I have been tasked with working on a database that I have never seen before and I'm looking at the DB structure. Some of the central and most heavily queried and joined tables look like virtual duplicates of each other. Here's a massively simplified representation of the situation, with business-sensitive information changed, listing hypothetical table names and fields: TopLevelGroup: PK_TLGroupId, DisplaysXOnBill, DisplaysYOnBill, IsInvoicedForJ, IsInvoicedForK SubGroup: PK_SubGroupId, FK_ParentTopLevelGroupId, DisplaysXOnBill, DisplaysYOnBill, IsInvoicedForJ, IsInvoicedForK SubSubGroup: PK_SubSUbGroupId, FK_ParentSubGroupId, DisplaysXOnBill, DisplaysYOnBill, IsInvoicedForJ, IsInvoicedForK I haven't listed the types of the fields as I don't think it's particularly important to the situation. In addition, it's worth saying that rather than four repeated fields as in the example above, I'm looking at 86 repeated fields. For the most part, those fields genuinely do represent "facts" about the primary table entity, so it's not automatically wrong for that reason. In addition, the "groups" represented here have a property inheritance relationship. If DisplaysXOnBill is NULL in the SubSubGroup, it takes the value of DisplaysXOnBillfrom it's parent, the SubGroup, and so-on up to the TopLevelGroup. Further, the requirements will never require that the model extends beyond three levels, so there is no need for flexibility in that area. Is there a design smell from several tables which describe very similar entities having almost identical fields? If so, what might be a better design of the example above? I'm using the phrase "design smell" to indicate a possible problem. Of course, in any given situation, a particular design might well be the best solution. I'm looking for a more general answer - wondering what might be wrong with this design and what might be the better design were that the case. Possibly related, but not primary questions: Is this database schema in a reasonably normal form (e.g. to 3NF), insofar as can be told from the information I've provided. I can't see a problem with the requirements of 2NF and 3NF, except in their inheriting the requirements of 1NF. Is 1NF satisfied though? Are repeating groups allowed in different tables? Is there a best-practice method for implementing the inheritance relationship in a database as I require? The method above feels clunky to me because any query on the SubSubGroup necessarily needs to join onto the SubGroup and the TopLevelGroup tables to collect inherited facts, which can make even trivial joins requiring facts from the SubSubGroup table rather long-winded. There are, of course, political considerations to making a relatively large change like this. For the purpose of this question, I'm happy to ignore that fact in the interests of keeping the answers ring-fenced to the technical problem.

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  • deleted gen folder, eclipse isn't generating it now :(

    - by LuxuryMode
    I accidentally deleted my gen folder and now, predictably, my resources are all messed up. I just created a gen folder myself and tried to project clean - that didn't work. Tried right-clicking project and going to android tools fix project properties - didn't work. Tried unchecking build automatically...didn't work. cleaned, closed project, closed eclipse, restarted, etc, etc. Nothing is working and I keep seeing this error: gen already exists but is not a source folder. Convert to a source folder or rename it. EDIT - OK was able to generate R.java, but now I'm getting crazy stuff in the console: [2011-06-14 17:06:11 - fastapp] Conversion to Dalvik format failed with error 1 [2011-06-14 17:06:42 - fastapp] Dx trouble processing "java/awt/font/NumericShaper.class": Ill-advised or mistaken usage of a core class (java.* or javax.*) when not building a core library. This is often due to inadvertently including a core library file in your application's project, when using an IDE (such as Eclipse). If you are sure you're not intentionally defining a core class, then this is the most likely explanation of what's going on. However, you might actually be trying to define a class in a core namespace, the source of which you may have taken, for example, from a non-Android virtual machine project. This will most assuredly not work. At a minimum, it jeopardizes the compatibility of your app with future versions of the platform. It is also often of questionable legality. If you really intend to build a core library -- which is only appropriate as part of creating a full virtual machine distribution, as opposed to compiling an application -- then use the "--core-library" option to suppress this error message. If you go ahead and use "--core-library" but are in fact building an application, then be forewarned that your application will still fail to build or run, at some point. Please be prepared for angry customers who find, for example, that your application ceases to function once they upgrade their operating system. You will be to blame for this problem. If you are legitimately using some code that happens to be in a core package, then the easiest safe alternative you have is to repackage that code. That is, move the classes in question into your own package namespace. This means that they will never be in conflict with core system classes. JarJar is a tool that may help you in this endeavor. If you find that you cannot do this, then that is an indication that the path you are on will ultimately lead to pain, suffering, grief, and lamentation. [2011-06-14 17:06:42 - fastapp] Dx 1 error; aborting [2011-06-14 17:06:42 - fastapp] Conversion to Dalvik format failed with error 1 And eclipse can't resolve the import of my resources import com.me.fastapp.R;

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  • Variable lenght arguments in log4cxx LOG4CXX_ macros

    - by Horacio
    I am using log4cxx in a big C++ project but I really don't like how log4cxx handles multiple variables when logging: LOG4CXX_DEBUG(logger, "test " << var1 << " and " << var3 " and .....) I prefer using printf like variable length arguments: LOG4CXX_DEBUG(logger, "test %d and %d", var1, var3) So I implemented this small wrapper on top of log4cxx #include <string.h> #include <stdio.h> #include <stdarg.h> #include <log4cxx/logger.h> #include "log4cxx/basicconfigurator.h" const char * log_format(const char *fmt, ...); #define MYLOG_TRACE(logger, fmt, ...) LOG4CXX_TRACE(logger, log_format(fmt, ## __VA_ARGS__)) #define MYLOG_DEBUG(logger, fmt, ...) LOG4CXX_DEBUG(logger, log_format(fmt, ## __VA_ARGS__)) #define MYLOG_INFO(logger, fmt, ...) LOG4CXX_INFO(logger, log_format(fmt, ## __VA_ARGS__)) #define MYLOG_WARN(logger, fmt, ...) LOG4CXX_WARN(logger, log_format(fmt, ## __VA_ARGS__)) #define MYLOG_ERROR(logger, fmt, ...) LOG4CXX_ERROR(logger, log_format(fmt, ## __VA_ARGS__)) #define MYLOG_FATAL(logger, fmt, ...) LOG4CXX_FATAL(logger, log_format(fmt, ## __VA_ARGS__)) static log4cxx::LoggerPtr logger(log4cxx::Logger::getRootLogger()); int main(int argc, char **argv) { log4cxx::BasicConfigurator::configure(); MYLOG_INFO(logger, "Start "); MYLOG_WARN(logger, log_format("In running this in %d threads safe?", 1000)); MYLOG_INFO(logger, "End "); return 0; } const char *log_format(const char *fmt, ...) { va_list va; static char formatted[1024]; va_start(va, fmt); vsprintf(formatted, 1024, fmt, va); va_end(va); return formatted; } And this works perfectly but I know using that static variable (formatted) can become problematic if I start using threads and each thread logging to the same place. I am no expert in log4cxx so I was wondering if the LOG4CXX macros are handling concurrent thread access automatically? or do I have to implement some sort of locking around the log_format method? something that I wan't to avoid due to performance implications. Also I would like to ask why if I replace the vsprintf inside the log_format method with vsnprintf (that is more secure) then I get nothing printed? To compile and test this program (in Ubuntu) use : g++ -o loggertest loggertest.cpp -llog4cxx

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  • How can I structure and recode messy categorical data in R?

    - by briandk
    I'm struggling with how to best structure categorical data that's messy, and comes from a dataset I'll need to clean. The Coding Scheme I'm analyzing data from a university science course exam. We're looking at patterns in student responses, and we developed a coding scheme to represent the kinds of things students are doing in their answers. A subset of the coding scheme is shown below. Note that within each major code (1, 2, 3) are nested non-unique sub-codes (a, b, ...). What the Raw Data Looks Like I've created an anonymized, raw subset of my actual data which you can view here. Part of my problem is that those who coded the data noticed that some students displayed multiple patterns. The coders' solution was to create enough columns (reason1, reason2, ...) to hold students with multiple patterns. That becomes important because the order (reason1, reason2) is arbitrary--two students (like student 41 and student 42 in my dataset) who correctly applied "dependency" should both register in an analysis, regardless of whether 3a appears in the reason column or the reason2 column. How Can I Best Structure Student Data? Part of my problem is that in the raw data, not all students display the same patterns, or the same number of them, in the same order. Some students may do just one thing, others may do several. So, an abstracted representation of example students might look like this: Note in the example above that student002 and student003 both are coded as "1b", although I've deliberately shown the order as different to reflect the reality of my data. My (Practical) Questions Should I concatenate reason1, reason2, ... into one column? How can I (re)code the reasons in R to reflect the multiplicity for some students? Thanks I realize this question is as much about good data conceptualization as it is about specific features of R, but I thought it would be appropriate to ask it here. If you feel it's inappropriate for me to ask the question, please let me know in the comments, and stackoverflow will automatically flood my inbox with sadface emoticons. If I haven't been specific enough, please let me know and I'll do my best to be clearer.

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  • Struggling with ASP.NET MVC auto-scaffolder template

    - by DanM
    I'm trying to write an auto-scaffolder template for Index views. I'd like to be able to pass in a collection of models or view-models (e.g., IQueryable<MyViewModel>) and get back an HTML table that uses the DisplayName attribute for the headings (th elements) and Html.Display(propertyName) for the cells (td elements). Each row should correspond to one item in the collection. Here's what I have so far: <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl" %> <% var items = (IQueryable<TestProj.ViewModels.TestViewModel>)Model; // How do I make this generic? var properties = items.First().GetMetadata().Properties .Where(pm => pm.ShowForDisplay && !ViewData.TemplateInfo.Visited(pm)); %> <table> <tr> <% foreach(var property in properties) { %> <th> <%= property.DisplayName %> </th> <% } %> </tr> <% foreach(var item in items) { HtmlHelper itemHtml = ????; // What should I put in place of "????"? %> <tr> <% foreach(var property in properties) { %> <td> <%= itemHtml.Display(property.DisplayName) %> </td> <% } %> </tr> <% } %> </table> Two problems with this: I'd like it to be generic. So, I'd like to replace var items = (IQueryable<TestProj.ViewModels.TestViewModel>)Model; with var items = (IQueryable<T>)Model; or something to that effect. A property Html is automatically created for me when the view is created, but this HtmlHelper applies to the whole collection. I need to somehow create an itemHtml object that applies just to the current item in the foreach loop. I'm not sure how to do this, however, because the constructors for HtmlHelper don't take a Model object. How do I solve these two problems?

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  • HTTP caching confusion

    - by Keith
    I'm not sure whether this is a server issue, or whether I'm failing to understand how HTTP caching really works. I have an ASP MVC application running on IIS7. There's a lot of static content as part of the site including lots of CSS, Javascript and image files. For these files I want the browser to cache them for at least a day - our .css, .js, .gif and .png files rarely change. My web.config goes like this: <system.webServer> <staticContent> <clientCache cacheControlMode="UseMaxAge" cacheControlMaxAge="1.00:00:00" /> </staticContent> </system.webServer> The problem I'm getting is that the browser (tested Chrome, IE8 and FX) doesn't seem to be caching the files as I'd expect. I've got the default settings (check for newer pages automatically in IE). On first visit the content downloads as expected HTTP/1.1 200 OK Cache-Control: max-age=86400 Content-Type: image/gif Last-Modified: Fri, 07 Aug 2009 09:55:15 GMT Accept-Ranges: bytes ETag: "3efeb2294517ca1:0" Server: Microsoft-IIS/7.0 X-Powered-By: ASP.NET Date: Mon, 07 Jun 2010 14:29:16 GMT Content-Length: 918 <content> I think that the Cache-Control: max-age=86400 should tell the browser not to request the page again for a day. Ok, so now the page is reloaded and the browser requests the image again. This time it gets an empty response with these headers: HTTP/1.1 304 Not Modified Cache-Control: max-age=86400 Last-Modified: Fri, 07 Aug 2009 09:55:15 GMT Accept-Ranges: bytes ETag: "3efeb2294517ca1:0" Server: Microsoft-IIS/7.0 X-Powered-By: ASP.NET Date: Mon, 07 Jun 2010 14:30:32 GMT So it looks like the browser has sent the ETag back (as a unique id for the resource), and the server's come back with a 304 Not Modified - telling the browser that it can use the previously downloaded file. It seems to me that would be correct for many caching situations, but here I don't want the extra round trip. I don't care if the image gets out of date when the file on the server changes. There are a lot of these files (even with sprite-maps and the like) and many of our clients have very slow networks. Each round trip to ping for that 304 status is taking about a 10th to a 5th of a second. Many also have IE6 which only has 2 HTTP connections at a time. The net result is that our application appears to be very slow for these clients with every page taking an extra couple of seconds to check that the static content hasn't changed. What response header am I missing that would cause the browser to aggressively cache the files? How would I set this in a .Net web.config for IIS7? Am I misunderstanding how HTTP caching works in the first place?

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  • Anyone have experience calling Rake from MSBuild for code gen and other benefits? How did it go? Wha

    - by Charlie Flowers
    While programming in C# using Visual Studio 2008, I often wish for "automatic" code generation. If possible, I'd like to achieve it by making my MSBuild solution file call out to Rake, which would call Ruby code for the code generation, having the resulting generated files automatically appear in my solution. Here's one business example (of many possible examples I could name) where this kind of automatic code generation would be helpful. In a recent project I had an interface with some properties that contained dollar amounts. I wanted a second interface and a third interface that had the same properties as the first interface, except they were "qualified" with a business unit name. Something like this: public interface IQuarterlyResults { double TotalRevenue { get; set; } double NetProfit { get; set; } } public interface IConsumerQuarterlyResults { double ConsumerTotalRevenue { get; set; } double ConsumerNetProfit { get; set; } } public interface ICorporateQuarterResults { double CorporateTotalRevenue { get; set; } double CorporateNetProfit { get; set; } } In this example, there is a "Consumer Business Unit" and a "Corporate Business Unit". Every property on IQuarterlyResults becomes a property called "Corporate" + [property name] on ICorporateQuarterlyResults, and likewise for IConsumerQuarterlyResults. Why make interfaces for these, rather than merely having an instance of IQuarterlyResults for Consumer and another instance for Corporate? Because, when working with the calculator object I was building, the user had to deal with 100's of properties, and it is much less confusing if he can deal with "fully qualified" property names such as "ConsumerNetProfit". But let's not get bogged down in this example. It is only an example and not the main question. The main question is this: I love using Ruby and ERB for code generation, and I love using Rake to manage dependencies between tasks. To solve the problem above, what I'd like to do is have MSBuild call out to Rake, and have Rake / Ruby read the list of properties on the "core" interface and then generate the code to make all the dependent interfaces and their properties. This would get triggered every time I do a build, because I'd put it into the MSBuild file for the VS.NET solution. Has anyone tried anything like this? How did it work out for you? What insights can you share about pros, cons, tips for success, etc.? Thanks!

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  • Why are these styles not visible in IE6

    - by Laramie
    Given the following markup <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML Strict//EN"><META http-equiv="Content-Type" content="text/html; charset=utf-8"> <HTML xmlns="http://www.w3.org/1999/xhtml"> <head> <style type="text/css"> div.apartBox { padding:12px; background: #FFFFFF; border: solid 1px #6182A3; } .browser { background: #fff; border: solid 1px #0055E3; border-top: solid 12px #0055E3; border-bottom: solid 4px #7A99C5; padding:10px 10px 8px 14px; color: #333; font: 0.8em/1 arial; margin: 8px 20px; } .callout { background: #EEF2F0; border: solid 1px #9CC7C0; padding:8px; } </style> </head> <BODY> <div class="apartBox" id="subPopout" style="Z-INDEX: 2; WIDTH: 400px; POSITION: relative"> <div id="upSubPop"> <div class="callout" id="subDetails"> <div class="browser"> <span id="txtExample">Me afecta que digan que soy incapaz.</span> </div> </div> </div> </div> </BODY></HTML> The styles from the css .browser and .callout are not visible in IE6 unless I manually remove the position:relative style from subPopout. This div is generated automatically from a modal popup so I unfortunately can't touch this style. It displays fine in FF. If I select the .browser div with my mouse, it displays when I unselect it!

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  • Overwrite values when using gridview Edit?

    - by sah302
    I am using a GridView which is bound to a LinqDataSource and using the automatic edit and delete buttons. However, I don't want the user to edit two of the columns manually, but done automatically. Specifically username who last updated the entry, and the date it was updated. The gridview only contains 3 columns: Name, Date modified, last updated by. Right now when the user clicks the edit button they can only edit the name column (other two set to read-only). Upon clicking the update button, I want the other 2 fields to update as well based on some extra code. I thought this was done in the code behind within the event rowUpdating, but it doesn't seem to work. My gridview: <asp:GridView ID="gvNewsSources" runat="server" AutoGenerateColumns="False" DataSourceID="ldsNewsSource" AutoGenerateDeleteButton="True" AutoGenerateEditButton="True" CellPadding="4" ForeColor="#333333" GridLines="None" DataKeyNames="Id"> <RowStyle BackColor="#F7F6F3" ForeColor="#333333" /> <Columns> <asp:BoundField DataField="Name" HeaderText="Name" SortExpression="Name" /> <asp:BoundField DataField="LastUpdatedBy" HeaderText="Last Updated By" SortExpression="LastUpdatedBy" ReadOnly="True" /> <asp:BoundField DataField="DatedModified" HeaderText="Dated Modified" SortExpression="DatedModified" ReadOnly="True" /> </Columns> <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" /> <SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" /> <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> <EditRowStyle BackColor="#999999" /> <AlternatingRowStyle BackColor="White" ForeColor="#284775" /> </asp:GridView> My code behind: Partial Class _Default Inherits System.Web.UI.Page Protected Sub gvNewsSources_RowUpdating(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewUpdateEventArgs) Handles gvNewsSources.RowUpdating e.NewValues("LastUpdatedBy") = GetUser.GetUserName e.NewValues("DateModified") = Date.Now() lblOutput.Text = e.NewValues("DateModified").ToString() End Sub End Class Yet when I run through this, I get no errors, but the values aren't being updated in the database or in the gridview. I ran through debug mode and the new values dictionary starts at 1 and ends up being 3 by the end of the rowUpdating event and the value is being set (tested by output the newValue of Datemodified), but it isn't saving. What am I doing wrong?

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  • How to properly downcast in C# with a SWIG generated interface?

    - by JG
    I've got a very large and mature C++ code base that I'm trying to use SWIG on to generate a C# interface for. I cannot change the actual C++ code itself but we can use whatever SWIG offers in the way of extending/updating it. I'm facing an issue where a function C++ is written as such: A* SomeClass::next(A*) The caller might do something like: A* acurr = 0; while( (acurr = sc->next(acurr)) != 0 ){ if( acurr isoftype B ){ B* b = (B*)a; ...do some stuff with b.. } elseif( acurr isoftype C ) ... } Essentially, iterating through a container elements that depending on their true type, do something different. The SWIG generated C# layer for the "next" function unfortunately does the following: return new A(); So the calling code in C# land cannot determine if the returned object is actually a derived class or not, it actually appears to always be the base class (which does make sense). I've come across several solutions: Use the %extend SWIG keyword to add a method on an object and ultimately call dynamic_cast. The downside to this approach, as I see it, is that this requires you to know the inheritance hierarchy. In my case it is rather huge and I see this is as a maintenance issue. Use the %factory keyword to supply the method and the derived types and have SWIG automatically generate the dynamic_cast code. This appears to be a better solution that the first, however upon a deeper look it still requires you to hunt down all the methods and all the possible derived types it could return. Again, a huge maintenance issue. I wish I had a doc link for this but I can't find one. I found out about this functionality by looking through the example code that comes with SWIG. Create a C# method to create an instance of the derived object and transfer the cPtr to the new instance. While I consider this clumsy, it does work. See an example below. public static object castTo(object fromObj, Type toType) { object retval = null; BaseClass fromObj2 = fromObj as BaseClass; HandleRef hr = BaseClass.getCPtr(fromObj2); IntPtr cPtr = hr.Handle; object toObj = Activator.CreateInstance(toType, cPtr, false); // make sure it actually is what we think it is if (fromObj.GetType().IsInstanceOfType(toObj)) { return toObj; } return retval; } Are these really the options? And if I'm not willing to dig through all the existing functions and class derivations, then I'm left with #3? Any help would be appreciated.

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  • How to Sync CI (Hudson) Activity into an existing automated Build Process (phing, svn)?

    - by maraspin
    OUR CURRENT BUILD PROCESS We're a small team of developers (2 to 4 people depending on project) who currently use Phing to deploy code to a staging environment, before going live. We keep our code in a SVN repo, where the trunk holds current active development and, at certain times, we do make branches that we test and then (if successful), tag and export to the staging env. If everything goes well there too, we finally deploy'em in production servers. Actions are highly automated, but always triggered by human intervention. THE DOUBT We'd now like to introduce Continuous Integration (with Hudson) in the process; unfortunately we have a few doubts about activity syncing, since we're afraid that CI could somewhat interfere with our build process and cause certain problems. Considering that an automated CI cycle has a certain frequency of automatically executed actions, we see 2 possible cases for "integration", each with its own problems: Case A: each CI cycle produces a new branch with its own name; we do use such a name to manually (through phing as it happens now) export the code from the SVN to the staging env. The problem I see here is that (unless specific countermeasures are taken - IE deletion) the number of branches we have can easily grow out of control (let's suppose we commit often, so that we have a fresh new build/branch every N minutes). Case B: each CI cycle creates a new branch named 'current', which is then tagged with a unique name only when we manually decide to export it to staging; the current branch, at any case is then deleted, as soon as the next CI cycle starts up. The problem we see here is that a new cycle could kick in while someone is tagging/exporting the 'current' branch to staging thus creating an inconsistent build (but maybe here I'm just too pessimist, since I confess I don't know whether SVN offers some built-in protection against this). With all this being said, I was wondering if anyone with similar experiences could be so kind to give us some hints on the subject, since none of the approaches depicted above looks completely satisfing to us. Is there something important we just completely left off in the overall picture? Thanks for your attention & (in advance) for your help!

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  • WCF facility : Metadata publishing for this service is currently disabled

    - by cvista
    I asked this before and got no where so i'm asking again as i'm now desperate!! Hey if i create a new wcf project i can browse the meta instantly. if I try - when using the WCF facility - i get the following: Metadata publishing for this service is currently disabled. i followed the instructions there and in a million other places and get no where. if i copy the contents of my faciltity service into the newly created project it complains that aspNetCompatibilityEnabled isnt enabled. so i enable it and then mex is disabled again and i get: Metadata publishing for this service is currently disabled. again!! this is driving me crazy - i have tried tried tried to follow every example on the web!! here is my current configuration - there is no client yet: <system.serviceModel> <serviceHostingEnvironment aspNetCompatibilityEnabled="true" /> <services> <service name="IbzStar.WebServices.UserServices" behaviorConfiguration="ServiceBehavior"> <!-- Service Endpoints --> <endpoint address="" binding="wsHttpBinding" contract="IbzStar.WebServices.IUserServices"> <!-- Upon deployment, the following identity element should be removed or replaced to reflect the identity under which the deployed service runs. If removed, WCF will infer an appropriate identity automatically. --> <identity> <dns value="localhost"/> </identity> </endpoint> <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"/> </service> </services> <behaviors> <serviceBehaviors> <behavior name="ServiceBehavior"> <!-- To avoid disclosing metadata information, set the value below to false and remove the metadata endpoint above before deployment --> <serviceMetadata httpGetEnabled="true"/> <!-- To receive exception details in faults for debugging purposes, set the value below to true. Set to false before deployment to avoid disclosing exception information --> <serviceDebug includeExceptionDetailInFaults="false"/> </behavior> </serviceBehaviors> </behaviors> </system.serviceModel> please someone help me out before my laptop gets launched into orbit!! w://

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  • File sizing issue in DOS/FAT

    - by Heather
    I've been tasked with writing a data collection program for a Unitech HT630, which runs a proprietary DOS operating system that can run executables compiled for 16-bit MS DOS with some restrictions. I'm using the Digital Mars C/C++ compiler, which is working well thus far. One of the application requirements is that the data file must be human-readable plain text, meaning the file can be imported into Excel or opened by Notepad. I'm using a variable length record format much like CSV that I've successfully implemented using the C standard library file I/O functions. When saving a record, I have to calculate whether the updated record is larger or smaller than the version of the record currently in the data file. If larger, I first shift all records immediately after the current record forward by the size difference calculated before saving the updated record. EOF is extended automatically by the OS to accommodate the extra data. If smaller, I shift all records backwards by my calculated offset. This is working well, however I have found no way to modify the EOF marker or file size to ignore the data after the end of the last record. Most of the time records will grow in size because the data collection program will be filling some of the empty fields with data when saving a record. Records will only shrink in size when a correction is made on an existing entry, or on a normal record save if the descriptive data in the record is longer than what the program reads in memory. In the situation of a shrinking record, after the last record in the file I'm left with whatever data was sitting there before the shift. I have been writing an EOF delimiter into the file after a "shrinking record save" to signal where the end of my records are and space-filling the remaining data, but then I no longer have a clean file until a "growing record save" extends the size of the file over the space-filled area. The truncate() function in unistd.h does not work (I'm now thinking this is for *nix flavors only?). One proposed solution I've seen involves creating a second file and writing all the data you wish to save into that file, and then deleting the original. Since I only have 4MB worth of disk space to use, this works if the file size is less than 2MB minus the size of my program executable and configuration files, but would fail otherwise. It is very likely that when this goes into production, users would end up with a file exceeding 2MB in size. I've looked at Ralph Brown's Interrupt List and the interrupt reference in IBM PC Assembly Language and Programming and I can't seem to find anything to update the file size or similar. Is reducing a file's size without creating a second file even possible in DOS?

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