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  • Server Push CGI Perl Problem writing the JPEG image

    - by Jujjuru
    I am a beginner in Perl CGI etc. I was experimenting with server-push concept with a piece of perl code. It is supposed to send a jpeg image to the client every 3 seconds. Unfortunately nothing seems to work. Can somebody help identify the problem? Here is the code.... use strict; # turn off io buffering $|=1; print "Content-type: multipart/x-mixed-replace;"; print "boundary=magicalboundarystring\n\n"; print "--magicalboundarystring\n"; #list the jpg images my(@file_list) = glob "*.jpg"; my($file) = ""; foreach $file(@file_list ) { open FILE,">", $file or die "Cannot open file $file: $!"; print "Content-type: image/jpeg\n\n"; while ( <FILE> ) { print "$_"; } close FILE; print "\n--magicalboundarystring\n"; sleep 3; next; } EDIT: added turn off i/o buffering, added "use strict" and "@file_list", "$file" are made local

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  • I have a problem with mysql and php

    - by neo skosana
    Hi I have a problem, this is my code: $db = new mysqli("localhost", "root", "", "blah"); $result1 = $db-query("select * from c_register where email = '$eml' and password = '$pass'"); if($result1-fetch_array()) { $auth->createSession(); $_SESSION['user'] = 'client'; promptUser("You have successfully logged in!!!","index.php"); } $db = new mysqli("localhost", "root", "", "blah"); $result2 = $db-query("select * from b_register where email = '$eml' and password = '$pass'"); if($result2-fetch_array()) { $auth->createSession(); $_SESSION['user'] = 'business'; promptUser("You have successfully logged in!!!","index.php"); } $db = new mysqli("localhost", "root", "", "blah"); $result3 = $db-query("select * from g_register where email = '$eml' and password = '$pass'"); if($result3-fetch_array()) { $auth->createSession(); $_SESSION['user'] = 'employee'; promptUser("You have successfully logged in!!!","index.php"); } $db = new mysqli("localhost", "root", "", "blah"); $result4 = $db-query("select * from k_register where email = '$eml' and password = '$pass'"); if($result4-fetch_array()) { $auth->createSession(); $_SESSION['user'] = 'super'; promptUser("You have successfully logged in!!!","index.php"); } else { promptUser("Username/Password do not match. Please try again!!!",""); } Funny enough this code works, but I no that I went about it the wrong way. I am new with php and mysql, so please help. I also tried e.gresult4->free(); for all the variable that save the data, and I got this error: Fatal error: Call to a member function free() on a non-object in...

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  • Copy recordset data into multiple sheets to avoid problem of maximum rows limit in Excel VBA

    - by Sam
    I am developing reporting application in Excel/vba 2003. VBA code sends search query to database and gets the data through recordset. It will then be copied to one of excel sheet. The rertrieved data looks like as shown below. ProductID--|---DateProcessed--|----State----- 1................|.. 1/1/2010..............|.....Picked Up 1................|.. 1/1/2010..............|.....Forward To Approver 1................|.. 1/2/2010..............|.....Approver Picked Up 1................|.. 1/3/2010..............|.....Approval Completed 2................|.. 1/1/2010..............|.....Picked Up 3................|.. 1/2/2010..............|.....Picked Up 3................|.. 1/2/2010..............|.....Forward To Approver The problem is data retrieved from search query is so huge that it goes above the excel row limit (65536 rows in excel 2003). So I want to split this data into two excel sheets. While spliting the data I want to ensure that the data for same product shoud remain in one sheet. For example, if the last record in the above result set is 65537th record then I also want to move all records for product 3 into new sheet. So sheet1 will contain records for product id 1 and 2 with total records = 65534. Sheet 2 will cotain records for product id 3 - with total records = 2. How can I acheive this in vba? If it is not possible, is there any alternative solution ? Thanks in Advance !

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  • Problem with sprintf function, last parameters are wrong when written

    - by Apoc
    So I use sprintf sprintf(buffer,"%f|%f|%f|%f|%f|%f|%d|%f|%d", x, y, z, u, v, w, nID,dDistance, nConfig) But when I print the buffer I get the 2 last parameters wrong, they are lets suppose to be 35.0000 and 0 and in the string they are 0.00000 and 10332430 and my buffer is long enough and all the other parameters are good in the string Any idea? Is there a length limit to sprintf or something^ I checked the types of all the numbers and they are right, but what seems to be the problem is the dDistance. When I remove it from the sprint, the nConfig gets the right value in the string, but when I remove nConfig, dDistance still doesn't get the right value. I checked and dDistance is a double. Any idea? Since people don't seem to believe me I did this : char test[255]={0}; int test1 = 2; double test2=35.00; int test3 = 0; sprintf(test,"%d|%f|%d",test1,test2,test3); and I get this in my string: 2|0.000000|1078034432

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  • problem with drag and drop for the winform using c#

    - by karthik
    I dont have the title bar in my winform, so i need to code drag and drop for the entire form. I am using the below code to do it, which works fine. I have two panels in my form, PanelA and PanelB. During the startup i show PanelA where the drag and drop works perfectly. Later when the user clicks the button in PannelA, i need to make PanelA visible false and show the PanelB My drag and drop is not working when the PanelB is loaded in form. Whats the problem here ? private void SerialPortScanner_MouseUp(object sender, MouseEventArgs e) { this.drag = false; } private void SerialPortScanner_MouseDown(object sender, MouseEventArgs e) { this.drag = true; this.start_point = new Point(e.X, e.Y); } private void SerialPortScanner_MouseMove(object sender, MouseEventArgs e) { if (this.drag) { Point p1 = new Point(e.X, e.Y); Point p2 = this.PointToScreen(p1); Point p3 = new Point(p2.X - this.start_point.X, p2.Y - this.start_point.Y); this.Location = p3; } }

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  • sqlite3 DELETE problem "Library Routine Called Out Of Sequence"

    - by Michael Bordelon
    Here is my second stupid Noob problem. I am trying to do a simple Delete and I keep blowing up on the prepare step. I already have other Deletes, Inserts, Updates and Selects working. I am sure it is something simple. I appreciate your help. + (void)flushTodaysWorkouts { sqlite3_stmt *statement = nil; //open the database if (sqlite3_open([[BIUtility getDBPath] UTF8String], &database) != SQLITE_OK) { sqlite3_close(database); NSAssert(0, @"Failed to opendatabase"); } NSArray *woList = [self todaysScheduledWorkouts]; for (Workout *wo in woList) { NSInteger woID = wo.woInstanceID; if(statement == nil) { const char *sql = "DELETE FROM IWORKOUT WHERE WOINSTANCEID = ?"; if(sqlite3_prepare_v2(database, sql, -1, &statement, NULL) != SQLITE_OK) NSAssert1(0, @"Error while creating delete statement. '%s'", sqlite3_errmsg(database)); } //When binding parameters, index starts from 1 and not zero. sqlite3_bind_int(statement, 1, woID); if (SQLITE_DONE != sqlite3_step(statement)) NSAssert1(0, @"Error while deleting. '%s'", sqlite3_errmsg(database)); sqlite3_finalize(statement); } if(database) sqlite3_close(database); }

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  • UserControl/TreeView Problem....Not getting result during runtime..

    - by Samiul
    Hi all, My problem is, I'm using a TreeView in a UserControl. While debugging, I can see the results are adding in the TreeView but it's not happening when I'm using that UserControl onto my MainForm. The UserControl containing the TreeView remains blank during runtime of the main application. I've also referenced the UserControl project with my Main project. Here I'm giving my code for helping me out. Thanks in advance. Code: In the UserControl class: public override void Refresh() { PopulateTreeView(); } private void PopulateTreeView() { TreeNodeCollection treeNodeCollection; treeNodeCollection = CreateParentNode("My Information"); CreateChildNode(treeNodeCollection, "Name"); CreateChildNode(treeNodeCollection, "Address"); this.Update(); myTreeView.ExpandAll(); } private TreeNodeCollection CreateParentNode(string parentNode) { TreeNode treeNode = new TreeNode(parentNode); myTreeView.Nodes.Add(treeNode); return treeNode.Nodes; } private void CreateChildNode(TreeNodeCollection nodeCollection, string itemName) { TreeNode treeNode = new TreeNode(itemName); nodeCollection.Add(treeNode); } In my MainForm: private void button1_Click(object sender, EventArgs e) { UserControl userControl = new UserControl(); userControl.Refresh(); }

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  • Apache redirection problem!!!!

    - by vikas
    Hi guys, I am setting up a pre-built website built in php. The site was actually hosted on the linux server. Now I am trying to set it up on a Window machine with WAMP server. In this website almost every page request passes through a particular file called redirect(which is basically a php file without extension). Now the problem is that when I inspected the configuration(httpd.conf, apache.conf,.htaccess, vhost.conf etc) of the apache server on the linux machine, I nowhere found the redirect rules for doing so. Neither mod_rewrite nor mod_alias rules for this redirection were found there. But is still redirects the request properly. I also noticed that Zend Framework library is there in the exact same directory where the redirect file is. This library is included in the include_path in php.ini. However, the web site is still not developed using Zend MVC and I have seen NO proof of ZEND being used there. So I am really confused how this redirection is working there? I am unable to set up this on window machine without rewrite rules of mod_rewrite or mod_alias. Do you guys know any alternative of both the said modules for redirection? I know the site is really weird, but i have to set it up. :) Thanks in advance for your help.

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  • regexp in java problem

    - by Staszek28
    Hello! I found some problem while testing my NLP system. I have a java regex "(.\.\s)*Dendryt.*" and for string "v Table of Contents List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . " it just dont stop computing. Its clear that this regex complexity is very high, I will try to refactor it. Have you some suggestions for me for a future regex development ??? Thanks.

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  • Decimal problem in Java

    - by Jerome
    I am experimenting with writing a java class for financial engineering (hobby of mine). The algorithm that I desire to implement is: 100 / 0.05 = 2000 Instead I get: 100 / 0.05 = 2000.9999999999998 I understand the problem to be one with converting from binary numbers to decimals (float -- int). I have looked at the BigDecimal class on the web but have not quite found what I am looking for. Attached is the program and a class that I wrote: // DCF class public class DCF { double rate; double principle; int period; public DCF(double $rate, double $principle, int $period) { rate = $rate; principle = $principle; period = $period; } // returns the console value public double consol() { return principle/rate; } // to string Method public String toString() { return "(" + rate + "," + principle + "," + period + ")"; } } Now the actual program: // consol program public class DCFmain { public static void main(String[] args) { // create new DCF DCF abacus = new DCF(0.05, 100.05, 5); System.out.println(abacus); System.out.println("Console value= " + abacus.consol() ); } } Output: (0.05,100.05,5) Console value= 2000.9999999999998 Thanks!

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  • Authentication Problem in Silverlight - Cannot connect to SQL Server

    - by Johann
    Hi All, At the moment, when I try to register a user using the default Business Template in Silverlight, I am getting an error. Basically I am following a tutorial found on Channel 9 on how to build a business app with Silverlight. "An error has occurred while establishing a connection to the server. (provider: Named Pipes Provider, error: 40 – Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 5) An error has occurred while establishing a connection to the server. When connecting to SQL Server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. (provider: Named Pipes Provider, error: 40 – Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 1326)". I found a blog where it identifies the problem, and followed every step, however I am still getting the same problems. Here is my connection string:- <add name="SIEventManagerEntities" connectionString="metadata=res://*/EventManagerDBModel.csdl|res://*/EventManagerDBModel.ssdl|res://*/EventManagerDBModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=MONFU-PC;Initial Catalog=SIEventManager;Integrated Security=SSPI;MultipleActiveResultSets=True&quot;" providerName="System.Data.EntityClient" /> Any help would really be very much appreciated! Thanks

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  • A problem regarding dll inheritance

    - by Adam
    Hello all I have created a dll that will be used by multiple applications, and have created an installer package that installs it to the program files, as well as adds it to the Global Assembly Cache. The dll itself uses log4net, and requires a xml file for the logging definitions. Therefore when the installer is run, the following files get copied to the install directory within program files: The main dll that I developed - The Log4Net.dll - the Log4Net.xml file I am now experiencing a problem. I have created a test console application for experimentation. I have added my dll as a reference, and set the 'local copy' flag to false. When I compile the test console exe however, I noticed that it has copied the log4net.dll and log4net.xml files to the bin directory. And when running the test console, it appears that it will only work if the log4net.dll is in the same directory as the exe. This is dispite the fact that the test console application does not use log4net, only the dll that was added as a reference does. Is there some way to have it so that the log4net.dll & xml files used will be the ones that were installed to the program files, rather than any application needed to copy over local copies? The applications that will be using my dll will not be using log4net, only the dll that they are referencing uses it. Many thanks

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  • Problem with passing vector of pointers to objects to member function of another object

    - by Jamesz
    Hi, I have a vector of pointers to Mouse objects called 'mice'. I'm passing the mice to the cat by reference. vector <Mouse*> mice; Cat * c; c->lookForMouse(&mice); And here's my lookForMouse() member function void Cat::lookForMouse(vector <Mouse*> *mice) { ... } And now to the problem! Within the function above, I can't seem to access my mice. This below will not work mice[i]->isActive(); The error message I receive suggests to use mice[i].isActive(), but this throws an error saying isActive() is not a member of std::vector<_Ty ... This works though... vector <Mouse*> miceCopy = *mice; miceCopy[i]->isActive(); I understand that I shouldn't be creating another vector of mice here, it defeats the whole point of passing it by reference (let me know if I'm wrong)... Why can't I do mice[i]-isActive() What should I be doing? Thanks for your time and help :D James.

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  • Problem with 2 levels of inheritance in hibernate mapping

    - by Seth
    Here's my class structure: class A class B extends A class C extends A class D extends C class E extends C And here are my mappings (class bodies omitted for brevity): Class A: @Entity @Inheritance(strategy=InheritanceType.SINGLE_TABLE) @MappedSuperclass @DiscriminatorColumn( name="className", discriminatorType=DiscriminatorType.STRING ) @ForceDiscriminator public abstract class A Class B: @Entity @DiscriminatorValue("B") public class B extends A Class C: @Entity @DiscriminatorValue("C") @MappedSuperclass @DiscriminatorColumn( name="cType", discriminatorType=DiscriminatorType.STRING ) @ForceDiscriminator public abstract class C extends A Class D: @Entity @DiscriminatorValue("D") public class D extends C Class E: @Entity @DiscriminatorValue("E") public class E extends C I've got a class F that contains a set of A: @Entity public class F { ... @OneToMany(fetch=FetchType.LAZY, cascade=CascadeType.ALL) @JoinTable( name="F_A", joinColumns = @JoinColumn(name="A_ID"), inverseJoinColumns = @JoinColumn(name="F_ID") ) private Set<A> aSet = new HashSet<A>(); ... The problem is that whenever I add a new E instance to aSet and then call session.saveOrUpdate(fInstance), hibernate saves with "A" as the discrimiator string. When I try to access the aSet in the F instance, I get the following exception (full stacktrace ommitted for brevity): org.hibernate.InstantiationException: Cannot instantiate abstract class or interface: path.to.class.A Am I mapping the classes incorrectly? How am I supposed to map multiple levels of inheritance? Thanks for the help!

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  • Social Media Java Design Problem

    - by jboyd
    I need to put something together quickly that will take blog posts and place them on social media sites, the requirements are as follows: Blog Entries are independent records that already exist, they have a published date and a modified date, the blog entry application cannot be changed, at least not substantially A new blog entry, or update needs to be sent to social media sites I currently do not need to update or delete social media communications if the blog entry is edited, or deleted, though I may need to later My design problems here are as follows: how do I know the status of each update how can I figure out what blog entry updates and postings have already been sent out? how can I quickly poll the blog entry table for postings that haven't yet been sent out? Avoiding looking at each Entry record from the DB as an object and asking if it's been sent already. That would be too slow. I cannot hook into any Blog Entry update code, my only option would be to create a trigger that an update queues something to be processed I'm looking for general guiding principles here, the biggest problem I'm having is coming up with any reasonable way to figure out if a blog entry should be sent to our social media sites in the first place

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  • Problem in getting response from server in jquery

    - by Alvin
    Hello, I'm using $.ajax(options) method to pass the request to server based on username and password, but whenever I try to print the response by XMLHttpRequest object when response gets successful, I'm getting an empty value. $(document).ready(function(){ $("#form").submit(function(){ $.ajax({url:"Chat.jsp",type:"POST",data:$("#form").serialize(),success:function(request) { alert(request.responseText); //This is displaying nothing },error:function(){document.write("YOU can't");}}); }); }); This is what I'm doing in my servlets code after executing query: try { String user = request.getParameter("j_username"); String password = request.getParameter("j_password"); if(user != null && password != null) { String query = "Select * from users where user_name="+"\'"+user+"\'"+"&& user_pass="+"\""+password+"\""; DBCheck db= new DBCheck(); boolean b = db.doExecuteQuery(con.createStatement(),query); response.setHeader("Cache-Control", "no-cache"); if(b) { response.getWriter().println("Username already exits"); } else { response.getWriter().println("Username doesn't exit"); } } } catch(SQLException ex) { ex.printStackTrace(); } } May I know the problem, and how can I fix it?

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  • Problem with SQL Server "EXECUTE AS"

    - by Vilx-
    I've got the following setup: There is a SQL Server DB with several tables that have triggers set on them (that collect history data). These triggers are CLR stored procedures with EXECUTE AS 'HistoryUser'. The HistoryUser user is a simple user in the database without a login. It has enough permissions to read from all tables and write to the history table. When I backup the DB and then restore it to another machine (Virtual Machine in this case, but it does not matter), the triggers don't work anymore. In fact, no impersonation for the user works anymore. Even a simple statement such as this exec ('select 3') as user='HistoryUser' produces an error: Cannot execute as the database principal because the principal "HistoryUser" does not exist, this type of principal cannot be impersonated, or you do not have permission. I read in MSDN that this can occur if the DB owner is a domain user, but it isn't. And even if I change it to anything else (their recommended solution) this problem remains. If I create another user without login, I can use it for impersonation just fine. That is, this works just fine: create user TestUser without login go exec ('select 3') as user='TestUser' I do not want to recreate all those triggers, so is there any way how I can make the existing HistoryUser work? Bump: Sorry, but this is kinda urgent...

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  • JTree TreePath casting problem

    - by newbie123
    I got this casting problem java.lang.String cannot be cast to java.io.File, when I trying to do this TreePath p = new TreePath(new Object[] {"src","file","My Diary" }); This is my jtree file model class FileTreeModel implements TreeModel { private FileNode root; public FileTreeModel(String directory) { root = new FileNode(directory); } public Object getRoot() { return root; } public Object getChild(Object parent, int index) { FileNode parentNode = (FileNode) parent; return new FileNode(parentNode, parentNode.listFiles()[index].getName()); } public int getChildCount(Object parent) { FileNode parentNode = (FileNode) parent; if (parent == null || !parentNode.isDirectory() || parentNode.listFiles() == null) { return 0; } return parentNode.listFiles().length; } public boolean isLeaf(Object node) { return (getChildCount(node) == 0); } public int getIndexOfChild(Object parent, Object child) { FileNode parentNode = (FileNode) parent; FileNode childNode = (FileNode) child; return Arrays.asList(parentNode.list()).indexOf(childNode.getName()); } public void valueForPathChanged(TreePath path, Object newValue) { } public void addTreeModelListener(TreeModelListener l) { } public void removeTreeModelListener(TreeModelListener l) { } } class FileNode extends java.io.File { public FileNode(String directory) { super(directory); } public FileNode(FileNode parent, String child) { super(parent, child); } @Override public String toString() { return getName(); } }

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  • jQuery AJAX PHP JSON problem

    - by Curro
    Hi Gurus I'm facing the problem of receiving an empty array when I do an AJAX request in the following way: This is the code I'm executing in JavaScript: <script type="text/javascript" src="lib/jquery.js"></script> <script type="text/javascript" src="lib/jquery.json.js"></script> <script type="text/javascript"> $(document).ready(function(){ /* Preparar JSON para el request */ var mJSON = new Object; mJSON.id_consulta = new Array; for (var i=0; i<3; i++){ mJSON.id_consulta[i] = new Object; mJSON.id_consulta[i].id = i; } var sJSON = $.toJSON(mJSON); $.ajax({ type: "POST", url: "getUbicaciones.php", data: sJSON, dataType: "json", contentType: "application/json; charset=utf-8", success: function(respuesta){ alert(respuesta); }, error: function (request,error){ alert("Error: " + request.statusText + ". " + error); } }); }); </script> And this is the code under PHP: <?php /* Decodificar JSON */ $m_decoded = $_POST; print_r($m_decoded); exit; ?> And all I get from this, using Chrome's Developer Tools is an empty array: Array ( ) Any clues on what am I doing wrong? The string sJSON is being encoded correctly, this is what I get when I do an "alert" on that one: {"id_consulta":[{"id":1},{"id":2},{"id":3}]} Thank you everyone in advance!

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  • Problem, executing commands in cmd using c#

    - by srk
    I need to execute the below command in command prompt. C:\MySQL\MySQL Server 5.0\bin>mysql -uroot -ppassword < d:/admindb/aar.sql When i do this manually in cmd, i am getting my results. Now i am trying to do this programatically, to execute it in cmd from c# code. I am using the below code to do it. I am not getting any errors and Result !!! When i debug, i get the value of string commandLine as below, "\"C:\\MySQL\\MySQL Server 5.0\\bin\\\" -uroot -ppassword > \"D:/admindb/AAR12.sql" I guess the problem is with this string, passed to cmd. How to solve this ??. public void Execute() { string commandLine = "\"" + MySqlCommandPath + "\"" + " -u" + DbUid + " -p" + DbPwd + " > " + "\"" + Path.Combine(Path_Backup, FileName_Backup + ExcID + ".sql"); System.Diagnostics.ProcessStartInfo PSI = new System.Diagnostics.ProcessStartInfo("cmd.exe"); PSI.RedirectStandardInput = true; PSI.RedirectStandardOutput = true; PSI.RedirectStandardError = true; PSI.UseShellExecute = false; System.Diagnostics.Process p = System.Diagnostics.Process.Start(PSI); System.IO.StreamWriter SW = p.StandardInput; System.IO.StreamReader SR = p.StandardOutput; SW.WriteLine(commandLine); SW.Close(); }

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  • Jtable live updating problem

    - by Fishinastorm
    Hi all, I'm trying to display a jtable in a pop up Jframe and am running into some problems. What i'am trying to do is as follows: catch a button action event in the main frame and display a pop up frame with a jtable populated with some data. The problem i have is that the jtable is populated with metadata i receive from a website and if i'm receiving many records, then the jtable is not displayed until all the records(metadata) is received from the website. I would like to change it such that as soon as the button event is detected in the main frame, I display the pop up frame along with the jtable and insert/update rows "as and when i receive the data from the website". In another words, i want to display the table and have the records appearing one at a time rather than displaying the jtable only after i receive all records.Below is how i'm trying to do it (but in vain :( ): ......... //add the table to the popup frame when application is started, but don't display the frame `until button action is //detected` extraInfoFrame.add(tblMetadata); extraInfoFrame.setVisible(false); //handle code for button press; display the popup private void butMetadataActionPerformed(java.awt.event.ActionEvent evt) { extraInfoFrame.pack(); extraInfoFrame.toFront(); //frame.setSize(350, 250); extraInfoFrame.setVisible(true); //retrieve rows data for the table for(int i=0;i<len;i++){ Object[] data=new Object[4];data=getMetadata(); //get model and insert row ((javax.swing.table.DefaultTableModel)tblMetadata.getModel()).insertRow(i,data); //tried something to notify the view abt change in table data ((javax.swing.table.DefaultTableModel)tblMetadata.getModel()).fireTableRowsInserted(0, 0); tblMetadata.revalidate(); tblMetadata.repaint(); } } Have been racking my head to try and figure something out. A sample example would be greatly appreciated.

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  • problem with implementing a simple work queue

    - by John Deerikio
    Hi all, I am having troubles with implementing a simple work queue. Doing some analysis, I am facing a subtle problem. The work queue is backed by a regular linked list. The code looks like this (simplified): 0. while (true) 1. while (enabled == true) 2. acquire lock on the list and get the next action to be executed (blocking operation) (store it in a local variable) 3. execute the action (outside the lock on the list on previous line) 4. get lock on this work queue 5. wait until this work queue has been notified (triggered when setEnabled(true) has been callled) The setEnabled(e) operation looks like this (simplified): enabled = e if (enabled == true) acquire lock on this work queue and do notify() Although this works, there is a condition in which a deadlock occurs. It happens in the following rare situation: while an action is being executed, setEnabled(false) is called just before step (4) is entered, setEnabled(true) is called now step (5) keeps waiting forever, because this work queue has already been notified How do I solve this? I have been looking at this for some time, but I cannot come up with a solution. Please note I am fairly new to thread synchronization. Thanks a lot.

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  • problem with two key ranges in couchdb

    - by Duasto
    I'm having problem getting the right results in my coordinate system. To explain my system, I have this simple database that have x_axis, y_axis and name columns. I don't need to get all the data, I just need to display some part of it. For example, I have a coordinate system that have 10:10(meaning from x_axis -10 to 10 and from y_axis -10 to 10) and I want to display only 49 coordinates. In sql query I can do it something like this: "select * from coordinate where x_axis = -3 and x_axis <= 3 and y_axis = -3 y_axis <= 3" I tried this function but no success: "by_range": { "map": "function(doc) { emit([doc.x_axis, doc.y_axis], doc) }" } by_range?startkey=[-3,-3]&endkey=[3,3] I got a wrong results of: -3x-3 -3x-2 -3x-1 -3x0 -3x1 -3x2 -3x3 <-- should not display this part -- -3x4 -3x5 -3x6 -3x7 -3x8 -3x9 -3x10 <-- end of should not display this part -- ..... up to 3x3 to give you a better understanding of my project here is the screenshot of that I want to be made: Oops they don't allowed new poster to post an image img96(dot)imageshack(dot)us/img96/5382/coordinates(dot)jpg <<< just change the "(dot)" to "."

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  • problem with kCFSocketReadCallBack

    - by zp26
    Hello. I have a problem with my program. I created a socket with "kCFSocketReadCallBack. My intention was to call the "acceptCallback" only when it receives a string to the socket. Instead my program does not just accept the connection always goes into "startReceive" stop doing so and sometimes crash the program. Can anybody help? Thanks readSocket = CFSocketCreateWithNative( NULL, fd, kCFSocketReadCallBack, AcceptCallback, &context ); static void AcceptCallback(CFSocketRef s, CFSocketCallBackType type, CFDataRef address, const void *data, void *info) // Called by CFSocket when someone connects to our listening socket. // This implementation just bounces the request up to Objective-C. { ServerVistaController * obj; #pragma unused(address) // assert(address == NULL); assert(data != NULL); obj = (ServerVistaController *) info; assert(obj != nil); #pragma unused(s) assert(s == obj->listeningSocket); if (type & kCFSocketAcceptCallBack){ [obj acceptConnection:*(int *)data]; } if (type & kCFSocketAcceptCallBack){ [obj startReceive:*(int *)data]; } } -(void)startReceive:(int)fd { CFReadStreamRef readStream = NULL; CFIndex bytes; UInt8 buffer[MAXLENGTH]; CFStreamCreatePairWithSocket( kCFAllocatorDefault, fd, &readStream, NULL); if(!readStream){ close(fd); [self updateLabel:@"No readStream"]; } CFReadStreamOpen(readStream); [self updateLabel:@"OpenStream"]; bytes = CFReadStreamRead( readStream, buffer, sizeof(buffer)); if (bytes < 0) { [self updateLabel:(NSString*)buffer]; close(fd); } CFReadStreamClose(readStream); }

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  • Problem with "moveable-only types" in VC++ 2010

    - by Luc Touraille
    I recently installed Visual Studio 2010 Professional RC to try it out and test the few C++0x features that are implemented in VC++ 2010. I instantiated a std::vector of std::unique_ptr, without any problems. However, when I try to populate it by passing temporaries to push_back, the compiler complains that the copy constructor of unique_ptr is private. I tried inserting an lvalue by moving it, and it works just fine. #include <utility> #include <vector> int main() { typedef std::unique_ptr<int> int_ptr; int_ptr pi(new int(1)); std::vector<int_ptr> vec; vec.push_back(std::move(pi)); // OK vec.push_back(int_ptr(new int(2)); // compiler error } As it turns out, the problem is neither unique_ptr nor vector::push_back but the way VC++ resolves overloads when dealing with rvalues, as demonstrated by the following code: struct MoveOnly { MoveOnly() {} MoveOnly(MoveOnly && other) {} private: MoveOnly(const MoveOnly & other); }; void acceptRValue(MoveOnly && mo) {} int main() { acceptRValue(MoveOnly()); // Compiler error } The compiler complains that the copy constructor is not accessible. If I make it public, the program compiles (even though the copy constructor is not defined). Did I misunderstand something about rvalue references, or is it a (possibly known) bug in VC++ 2010 implementation of this feature?

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