Search Results

Search found 21111 results on 845 pages for 'null pointer'.

Page 533/845 | < Previous Page | 529 530 531 532 533 534 535 536 537 538 539 540  | Next Page >

  • Is there a fundamental difference between malloc and HeapAlloc (aside from the portability)?

    - by Lambert
    Hi, I'm having code that, for various reasons, I'm trying to port from the C runtime to one that uses the Windows Heap API. I've encountered a problem: If I redirect the malloc/calloc/realloc/free calls to HeapAlloc/HeapReAlloc/HeapFree (with GetProcessHeap for the handle), the memory seems to be allocated correctly (no bad pointer returned, and no exceptions thrown), but the library I'm porting says "failed to allocate memory" for some reason. I've tried this both with the Microsoft CRT (which uses the Heap API underneath) and with another company's run-time library (which uses the Global Memory API underneath); the malloc for both of those works well with the library, but for some reason, using the Heap API directly doesn't work. I've checked that the allocations aren't too big (= 0x7FFF8 bytes), and they're not. The only problem I can think of is memory alignment; is that the case? Or other than that, is there a fundamental difference between the Heap API and the CRT memory API that I'm not aware of? If so, what is it? And if not, then why does the static Microsoft CRT (included with Visual Studio) take some extra steps in malloc/calloc before calling HeapAlloc? I'm suspecting there's a difference but I can't think of what it might be. Thank you!

    Read the article

  • Mulit-dimensional array edge/border conditions

    - by kirbuchi
    Hi, I'm iterating over a 3 dimensional array (which is an image with 3 values for each pixel) to apply a 3x3 filter to each pixel as follows: //For each value on the image for (i=0;i<3*width*height;i++){ //For each filter value for (j=0;j<9;j++){ if (notOutsideEdgesCondition){ *(**(outArray)+i)+= *(**(pixelArray)+i-1+(j%3)) * (*(filter+j)); } } } I'm using pointer arithmetic because if I used array notation I'd have 4 loops and I'm trying to have the least possible number of loops. My problem is my notOutsideEdgesCondition is getting quite out of hands because I have to consider 8 border cases. I have the following handled conditions Left Column: ((i%width)==0) && (j%3==0) Right Column: ((i-1)%width ==0) && (i>1) && (j%3==2) Upper Row: (i<width) && (j<2) Lower Row: (i>(width*height-width)) && (j>5) and still have to consider the 4 corner cases which will have longer expressions. At this point I've stopped and asked myself if this is the best way to go because If I have a 5 line long conditional evaluation it'll not only be truly painful to debug but will slow the inner loop. That's why I come to you to ask if there's a known algorithm to handle this cases or if there's a better approach for my problem. Thanks a lot.

    Read the article

  • NSCollectionView: Can the same object not be in the array more than once or is this a bug?

    - by Sean
    I may be doing this all wrong, but I thought I was on the right track until I hit this little snag. Basically I was putting together a toy using NSCollectionView and trying to understand how to hook that all up using IB. I have a button which will add a couple of strings to the NSArrayController: The first time I press this button, my strings appear in the collection view as expected: The second time I press the button, the views scroll down and room is made - but the items don't appear to get added. I just see blank space: The button is implemented as follows (controller is a pointer to the NSArrayController I added in IB): - (IBAction)addStuff:(id)control { [controller addObjects:[NSArray arrayWithObjects:@"String 1",@"String 2",@"String 3",nil]]; } I'm not sure what I'm doing wrong. Rather than try to explain all the connections/binds/etc, if you need more info, I'd be grateful if you could just take a quick look at the toy project itself. UPDATE: After more experimentation as suggested by James Williams, it seems the problem stems from having multiple objects with the same memory address in the array. This confuses either NSArrayController or NSCollectionView (not sure which). Changing my addStuff: to this resulted in the behavior I originally expected: [controller addObjects:[NSArray arrayWithObjects:[NSMutableString stringWithString:@"String 1"],[NSMutableString stringWithString:@"String 2"],[NSMutableString stringWithString:@"String 3"],nil]]; So the question now, I guess, is if this is a bug I should report to Apple or if this is intended/documented behavior and I just missed it?

    Read the article

  • Implementation/interface inheritance design question.

    - by Neil G
    I would like to get the stackoverflow community's opinion on the following three design patterns. The first is implementation inheritance; the second is interface inheritance; the third is a middle ground. My specific question is: Which is best? implementation inheritance: class Base { X x() const = 0; void UpdateX(A a) { y_ = g(a); } Y y_; } class Derived: Base { X x() const { return f(y_); } } interface inheritance: class Base { X x() const = 0; void UpdateX(A a) = 0; } class Derived: Base { X x() const { return x_; } void UpdateX(A a) { x_ = f(g(a)); } X x_; } middle ground: class Base { X x() const { return x_; } void UpdateX(A a) = 0; X x_; } class Derived: Base { void UpdateX(A a) { x_ = f(g(a)); } } I know that many people prefer interface inheritance to implementation inheritance. However, the advantage of the latter is that with a pointer to Base, x() can be inlined and the address of x_ can be statically calculated.

    Read the article

  • Interchange structured data between Haskell and C

    - by Eonil
    First, I'm a Haskell beginner. I'm planning integrating Haskell into C for realtime game. Haskell does logic, C does rendering. To do this, I have to pass huge complexly structured data (game state) from/to each other for each tick (at least 30 times per second). So the passing data should be lightweight. This state data may laid on sequential space on memory. Both of Haskell and C parts should access every area of the states freely. In best case, the cost of passing data can be copying a pointer to a memory. In worst case, copying whole data with conversion. I'm reading Haskell's FFI(http://www.haskell.org/haskellwiki/FFICookBook#Working_with_structs) The Haskell code look specifying memory layout explicitly. I have a few questions. Can Haskell specify memory layout explicitly? (to be matched exactly with C struct) Is this real memory layout? Or any kind of conversion required? (performance penalty) If Q#2 is true, Any performance penalty when the memory layout specified explicitly? What's the syntax #{alignment foo}? Where can I find the document about this? If I want to pass huge data with best performance, how should I do that? *PS Explicit memory layout feature which I said is just C#'s [StructLayout] attribute. Which is specifying in-memory position and size explicitly. http://www.developerfusion.com/article/84519/mastering-structs-in-c/ I'm not sure Haskell has matching linguistic construct matching with fields of C struct.

    Read the article

  • Approaches to replace cursor in pure AS3 / Flare project?

    - by peteorpeter
    Hi there good lookin, I've got a pure AS3 (no Flex) project that uses Flare to display and interact with a data visualization. I just implemented some panning behavior, so you can click and drag the visualization around, and now I'd like to give the user a visual indicator that this is possible, by switching the arrow cursor with a nice grabby-looking hand icon. The user can click and drag at any time except when the mouse is over a clickable node (at which time the cursor swaps to a pointer - this behavior is already in place). So... 1) Do I need to create my own custom bitmap/sprite or is there a palette of built-in cursors I can use? (I'm not using Flex.) 2) Is there a way to simply replace the default arrow with the pan cursor project-wide, or do I need to attach the swapping to mouse events on display objects? Can I use the stage object to make this behavior apply everywhere? 3) How do I perform the swap? Do I use the Cursor object directly or do I need to get involved with the CursorManager? Any guidance, pseudo-code, or words of wisdom is greatly appreciated!

    Read the article

  • Only root object on request is deserialized when using Message.GetBody<>

    - by user324627
    I am attempting to create a wcf service that accepts any input (Action="*") and then deserialize the message after determining its type. For the purposes of testing deserialization I am currently hard-coding the type for the test service. I get no errors from the deserialization process, but only the outer object is populated after deserialization occurs. All inner fields are null. I can process the same request against the original wcf service successfully. I am deserializing this way, where knownTypes is a type list of expected types: DataContractSerializer ser = new DataContractSerializer(new createEligibilityRuleSet ().GetType(), knownTypes); createEligibilityRuleSet newReq = buf.CreateMessage().GetBody<createEligibilityRuleSet>(ser); Here is the class and sub-classes of the request object. These classes are generated by svcutil using a top down approach from an existing wsdl. I have tried replacing the XmlTypeAttributes with DataContracts and the XmlElements with DataMembers with no difference. It is the instance of CreateEligibilityRuleSetSvcRequest on the createEligibilityRuleSet object that is null. I have included the request retrieved from the request at the bottom /// <remarks/> [System.CodeDom.Compiler.GeneratedCodeAttribute("svcutil", "3.0.4506.2152")] [System.SerializableAttribute()] [System.Diagnostics.DebuggerStepThroughAttribute()] [System.ComponentModel.DesignerCategoryAttribute("code")] [System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true, Namespace = "http://RulesEngineServicesLibrary/RulesEngineServices")] public partial class createEligibilityRuleSet { private CreateEligibilityRuleSetSvcRequest requestField; /// <remarks/> [System.Xml.Serialization.XmlElementAttribute(Form = System.Xml.Schema.XmlSchemaForm.Unqualified, IsNullable = true, Order = 0)] public CreateEligibilityRuleSetSvcRequest request { get { return this.requestField; } set { this.requestField = value; } } } /// <remarks/> [System.CodeDom.Compiler.GeneratedCodeAttribute("svcutil", "3.0.4506.2152")] [System.SerializableAttribute()] [System.Diagnostics.DebuggerStepThroughAttribute()] [System.ComponentModel.DesignerCategoryAttribute("code")] [System.Xml.Serialization.XmlTypeAttribute(Namespace = "http://RulesEngineServicesLibrary")] public partial class CreateEligibilityRuleSetSvcRequest : RulesEngineServicesSvcRequest { private string requestField; /// <remarks/> [System.Xml.Serialization.XmlElementAttribute(Form = System.Xml.Schema.XmlSchemaForm.Unqualified, Order = 0)] public string request { get { return this.requestField; } set { this.requestField = value; } } } [System.Xml.Serialization.XmlIncludeAttribute(typeof(CreateEligibilityRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(ApplyMemberEligibilitySvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(CreateCompletionCriteriaRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(CopyRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(DeleteRuleSetByIDSvcRequest))] [System.CodeDom.Compiler.GeneratedCodeAttribute("svcutil", "3.0.4506.2152")] [System.SerializableAttribute()] [System.Diagnostics.DebuggerStepThroughAttribute()] [System.ComponentModel.DesignerCategoryAttribute("code")] [System.Xml.Serialization.XmlTypeAttribute(Namespace = "http://RulesEngineServicesLibrary")] public partial class RulesEngineServicesSvcRequest : ServiceRequest { } /// <remarks/> [System.Xml.Serialization.XmlIncludeAttribute(typeof(RulesEngineServicesSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(CreateEligibilityRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(ApplyMemberEligibilitySvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(CreateCompletionCriteriaRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(CopyRuleSetSvcRequest))] [System.Xml.Serialization.XmlIncludeAttribute(typeof(DeleteRuleSetByIDSvcRequest))] [System.CodeDom.Compiler.GeneratedCodeAttribute("svcutil", "3.0.4506.2152")] [System.SerializableAttribute()] [System.Diagnostics.DebuggerStepThroughAttribute()] [System.ComponentModel.DesignerCategoryAttribute("code")] [System.Xml.Serialization.XmlTypeAttribute(Namespace = "http://FELibrary")] public partial class ServiceRequest { private string applicationIdField; /// <remarks/> [System.Xml.Serialization.XmlElementAttribute(Form = System.Xml.Schema.XmlSchemaForm.Unqualified, Order = 0)] public string applicationId { get { return this.applicationIdField; } set { this.applicationIdField = value; } } } Request from client comes on Message body as below. Retrieved from Message at runtime. <soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope" xmlns:rul="http://RulesEngineServicesLibrary/RulesEngineServices"> <soap:Header/> <soap:Body> <rul:createEligibilityRuleSet> <request> <applicationId>test</applicationId> <request>Perf Rule Set1</request> </request> </rul:createEligibilityRuleSet> </soap:Body> </soap:Envelope>

    Read the article

  • Invoking a function (main()) from a binary file in C

    - by Dhara Darji
    I have simple c program like, my_bin.c: #include <stdio.h> int main() { printf("Success!\n"); return 0; } I compile it with gcc and got executable: my_bin. Now I want to invoke main (or run this my_bin) using another C program. That I did with mmap and function pointer like this: #include <stdio.h> #include <fcntl.h> #include <sys/mman.h> int main() { void (*fun)(); int fd; int *map; fd = open("./my_bin", O_RDONLY); map = mmap(0, 8378, PROT_READ, MAP_SHARED, fd, 0); fun = map; fun(); return 0; } PS: I went through some tutorial, for how to read binary file and execute. But this gives Seg fault, any help appreciated! Thanks!

    Read the article

  • css style remains after click

    - by rod
    Hi All, I have a simple test page with a single styled button. I'm using a:hover when you hover over the button. However, when you click the button the a:hover style remains until I click on something else. How would I fix this and why is this happening? Thanks, rod. <asp:Content ID="indexContent" ContentPlaceHolderID="MainContent" runat="server"> <% using (Ajax.BeginForm(new AjaxOptions { })) { %> <div id="detailActions"> <a href="#">Delete User</a> </div> <% } %> </asp:Content> My CSS: #detailActions { margin-bottom: 7px; padding: 3px 0px 5px 0px; } #detailActions { padding: 1px 7px 1px 7px; margin: 0px 5px 0px 0px; border: solid 1px gray; background-color: #ADD8E6; cursor: pointer; width: auto !important; font-weight: bold; text-decoration: none; color: #003366; font-size: 1.2em; } #detailActions a:hover, #detailActions a:active, #detailActions a:focus { color: White; background-color: #00008B; }

    Read the article

  • Who's setting TCP window size down to 0, Indy or Windows?

    - by François
    We have an application server which have been observed sending headers with TCP window size 0 at times when the network had congestion (at a client's site). We would like to know if it is Indy or the underlying Windows layer that is responsible for adjusting the TCP window size down from the nominal 64K in adaptation to the available throughput. And we would be able to act upon it becoming 0 (nothing gets send, users wait = no good). So, any info, link, pointer to Indy code are welcome... Disclaimer: I'm not a network specialist. Please keep the answer understandable for the average me ;-) Note: it's Indy9/D2007 on Windows Server 2003 SP2. More gory details: The TCP zero window cases happen on the middle tier talking to the DB server. It happens at the same moments when end users complain of slowdowns in the client application (that's what triggered the network investigation). 2 major Network issues causing bottlenecks have been identified. The TCP zero window happened when there was network congestion, but may or may not be caused by it. We want to know when that happen and have a way to do something (logging at least) in our code. So where to hook (in Indy?) to know when that condition occurs?

    Read the article

  • using string to read file - XCode

    - by Fernando
    The following does not work and gives me a SIGABRT when I run in the debugger: std::ifstream inFile; inFile.open("/Users/fernandonewyork/inputText.txt"); cout << inFile << endl; vector<string> inText; if (inFile) { string s4; while (inFile>>s4) { inText.push_back(s4); } } inFile.close(); The following does: std::ifstream inFile; inFile.open("/Users/fernandonewyork/inputText.txt"); cout << inFile << endl; vector<string> inText; if (inFile) { string s4("This is no lnger an empty string"); while (inFile>>s4) { inText.push_back(s4); } } inFile.close(); I was under the impression I was able to simply use s4 without having to worry about any space considerations, or is something else happening here? This is the full error I get from the top code: malloc: * error for object 0x100010a20: pointer being freed was not allocated * set a breakpoint in malloc_error_break to debug Program received signal: “SIGABRT”.

    Read the article

  • how can udp data can passed through RS232 in ansi c?

    - by moon
    i want to transmit and receive data on RS232 using udp and i want to know about techniques which allow me to transmit and receive data on a faster rate and also no lose of data is there? thanx in advance. i have tried but need improvements if possible #include <stdio.h> #include <dos.h> #include<string.h> #include<conio.h> #include<iostream.h> #include<stdlib.h> #define PORT1 0x3f8 void main() { int c,ch,choice,i,a=0; char filename[30],filename2[30],buf; FILE *in,*out; clrscr(); while(1){ outportb(PORT1+0,0x03); outportb(PORT1+1,0); outportb(PORT1+3,0x03); outportb(PORT1+2,0xc7); outportb(PORT1+4,0x0b); cout<<"\n==============================================================="; cout<<"\n\t*****Serial Communication By BADR-U-ZAMAN******\nCommunication between two computers By serial port"; cout<<"\nPlease select\n[1]\tFor sending file \n[2]\tFor receiving file \n[3]\tTo exit\n"; cout<<"=================================================================\n"; cin>>choice; if(choice==1) { strcpy(filename,"C:\\TC\\BIN\\badr.cpp"); cout<<filename; for(i=0;i<=strlen(filename);i++) outportb(PORT1,filename[i]); in=fopen(filename,"r"); if (in==NULL) { cout<<"cannot open a file"; a=1; } if(a!=1) cout<<"\n\nFile sending.....\n\n"; while(!feof(in)) { buf=fgetc(in); cout<<buf; outportb(PORT1,buf); delay(5); } } else { if(choice==3) exit(0); i=0; buf='a'; while(buf!=NULL) { c=inportb(PORT1+5); if(c&1) { buf=inportb(PORT1); filename2[i]=buf; i++; } } out=fopen(filename2,"t"); cout<<"\n Filename received:"<<filename[2]; cout<<"\nReading from the port..."; cout<<"writing to file"<<filename2; do { c=inportb(PORT1+5); if(c&1) { buf=inportb(PORT1); cout<<buf; fputc(buf,out); delay(5); } if(kbhit()) { ch=getch(); } }while(ch!=27); } getch(); } }

    Read the article

  • OSMF seek with Amazon Cloudfront

    - by giorrrgio
    I've written a little OSMF player that streams via RTMP from Amazon Cloudfront. There's a known issue, the mp3 duration is not correctly readed from metadata and thus the seek function is not working. I know there's a workaround implying the use of getStreamLength function of NetConnection, which I successfully implemented in a previous non-OSMF player, but now I don't know how and when to call it, in terms of OSMF Events and Traits. This code is not working: protected function initApp():void { //the pointer to the media var resource:URLResource = new URLResource( STREAMING_PATH ); // Create a mediafactory instance mediaFactory = new DefaultMediaFactory(); //creates and sets the MediaElement (generic) with a resource and path element = mediaFactory.createMediaElement( resource ); var loadTrait:NetStreamLoadTrait = element.getTrait(MediaTraitType.LOAD) as NetStreamLoadTrait; loadTrait.addEventListener(LoaderEvent.LOAD_STATE_CHANGE, _onLoaded); player = new MediaPlayer( element ); //Marker 5: Add MediaPlayer listeners for media size and current time change player.addEventListener( DisplayObjectEvent.MEDIA_SIZE_CHANGE, _onSizeChange ); player.addEventListener( TimeEvent.CURRENT_TIME_CHANGE, _onProgress ); initControlBar(); } private function onGetStreamLength(result:Object):void { Alert.show("The stream length is " + result + " seconds"); duration = Number(result); } private function _onLoaded(e:LoaderEvent):void { if (e.newState == LoadState.READY) { var loadTrait:NetStreamLoadTrait = player.media.getTrait(MediaTraitType.LOAD) as NetStreamLoadTrait; if (loadTrait && loadTrait.netStream) { var responder:Responder = new Responder(onGetStreamLength); loadTrait.connection.call("getStreamLength", responder, STREAMING_PATH); } } }

    Read the article

  • JSP Upload File Java.lang.NullPointer

    - by newbie123
    I want to develope upload and download file from server. Upload.html <form action="/UploadFile/UploadFile" method="POST" enctype="multipart/form-data">Select a file: <input type="submit" name="button" /> <input type="file" name="first"></form> UploadFile.servlet protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String temp = request.getParameter("first"); System.out.println(temp); File origFile = new File(temp); FileOutputStream out = new FileOutputStream(request.getContextPath() + "pdtImages/" + "FirstFile"); InputStream ins = new FileInputStream(origFile); try { System.out.println(request.getContextPath()); byte[] buf = new byte[1024]; int len; while ((len = ins.read(buf)) > 0) { out.write(buf, 0, len); } out.close(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } When I submitted the file I got null pointer error message. I not very familiar with jsp can anybody help me? I want to store the file to the server directory.

    Read the article

  • Make an element visible to the user but invisible to events

    - by Acorn
    I'm not quite sure how to describe what I'm looking to do, but I'll do my best. At the moment I have a parent <div>, with absolutely positioned child <div>s within it, and I'm tracking the mouse pointer location coordinates relative to the element your mouse is over. At the moment, when I mouse over my child <div>s, I get the mouse location relative to them, but I want the coordinates to be relative the the parent <div> even when mousing over the child elements. So I basically want the child elements to be visible, but transparent to the mousemove, so I want the mousemove to go straight through to the parent element. How would I do this? Do I maybe need to somehow make the parent <div> be in the forground but still have the child <div>s show through? or make a transparent <div> overlay just to get the mouse coordinates? Here's a link to the page I'm experimenting on: http://acorn.host22.com/mouse.html

    Read the article

  • scanf segfaults and various other anomalies inside while loop

    - by Shadow
    while(1){ //Command prompt char *command; printf("%s>",current_working_directory); scanf("%s",command);<--seg faults after input has been received. printf("\ncommand:%s\n",command); } I am getting a few different errors and they don't really seem reproducible(except for the segfault at this point .<). This code worked fine about 10 minutes ago, then it infinite looped the printf command and now it seg faults on the line mentioned above. The only thing I changed was scanf("%s",command); to what it currently is. If I change the command variable to be an array it works, obviously this is because the storage is set aside for it. 1) I got prosecuted about telling someone that they needed to malloc a pointer* (But that usually seems to solve the problem such as making it an array) 2) the command I am entering is "magic" 5 characters so there shouldn't be any crazy stack overflow. 3) I am running on mac OSX 10.6 with newest version of xCode(non-OS4) and standard gcc 4) this is how I compile the program: gcc --std=c99 -W sfs.c Just trying to figure out what is going on. Being this is for a school project I am never going to have to see again, I will just code some noob work around that would make my boss cry :) But for afterwards I would love to figure out why this is happening and not just make some fix for it, and if there is some fix for it why that fix works.

    Read the article

  • retrieving value from database in java

    - by Akcire Atienza
    I am making AGAIN another program that retrieves the inputted data/values of fields from the database I created. but this time, my inputted value will be coming from the JtextField I created. I wonder what's wrong in here bec when I'm running it the output is always null. in this program i will convert the inputted value of my JTextField into int. here it is: public class ButtonHandler implements ActionListener { public void actionPerformed(ActionEvent e) { if(e.getSource() == extendB) { ExtensionForm extend = new ExtensionForm(); extend.setVisible(true); } else if(e.getSource()== searchB) { //get text from the textField String guest = guestIDTF.getText(); //parse the string to integer for retrieving of data int id = Integer.parseInt(guest); GuestsInfo guestInfo = new GuestsInfo(id); Room roomInfo = new Room(id); String labels[] = {guestInfo.getFirstName()+" "+guestInfo.getLastName(),""+roomInfo.getRoomNo(),roomInfo.getRoomType(),guestInfo.getTime(),"11:00"}; for(int z = 0; z<labels.length; z++) { labelDisplay[z].setText(labels[z]); } in my second class it retrieves the inputted values of fields from the database I created here's the code: import java.sql.*; public class Room { private String roomType; private int guestID, roomNo; private Connection con; private PreparedStatement statement; public Room(){ try { Class.forName("com.mysql.jdbc.Driver"); con = DriverManager.getConnection( "jdbc:mysql://localhost:3306/3moronsdb","root",""); } catch (Exception e) { e.printStackTrace(); } } public Room(int guestsID) { this(); try{ statement = con.prepareStatement("SELECT * FROM guest WHERE guestID=?"); statement.setInt(1, guestID); ResultSet rs = statement.executeQuery(); while(rs.next()){ this.guestID = rs.getInt(1); this.roomType = rs.getString(2); this.roomNo = rs.getInt(3); } }catch(Exception e){ System.out.print(e); } } //Constructor for setting rate public Room(String roomType, int roomNo) { this(); try { statement = con.prepareStatement("Insert into room(roomType, roomNo) values(?,?)"); statement.setString(1, roomType); statement.setInt(2, roomNo); statement.executeUpdate(); } catch(Exception e) { e.printStackTrace(); return; } } //getting roomType public String getRoomType(){ return roomType; } //getting roomNo public int getRoomNo(){ return roomNo; } //getting guestID public int getGuestId(){ return guestID; } } i already insert some values in my 3moronsdb which are ( 1, Classic , 103). here's my TEST main class: public class TestMain { public static void main(String [] a){ GuestsInfo guest = new GuestsInfo(1); //note that this instantiation is the other class which i just ask the other day.. (http://stackoverflow.com/questions/12762835/retrieving-values-from-database-in-java) Room rum = new Room(1); System.out.print(rum.getRoomType()+" "+ guest.getFirstName()); } } when i'm running it it only gives me null output for the Room class but i am getting the output of the GuestsInfo class which is 'Ericka'. Can you help me guys? I know I ask this kind of problem yesterday but i really don't know what's wrong in here now..

    Read the article

  • JQuery drag, drop and save via cookie - how to?

    - by RussP
    Sorry to be back folks, but you guys & girls seem to know much more about this than I do ... anyhow, here is my question/problem I want to use drag, drop, sort (the interface plugin does me even though I have read it's out of date? but have looked at UI and to be honest is not clear and to me appears heavier than interface?) Anyhow, how do I set a cookie to save positions from this: $(document).ready( function () { $('a.closeEl').bind('click', toggleContent); $('div.groupWrapper').Sortable( { accept: 'groupItem', helperclass: 'sortHelper', activeclass : 'sortableactive', hoverclass : 'sortablehover', handle: 'div.itemHeader', tolerance: 'pointer', onChange : function(ser) { }, onStart : function() { $.iAutoscroller.start(this, document.getElementsByTagName('body')); }, onStop : function() { $.iAutoscroller.stop(); } } ); } ); var toggleContent = function(e) { var targetContent = $('div.itemContent', this.parentNode.parentNode); if (targetContent.css('display') == 'none') { targetContent.slideDown(300); $(this).html('[-]'); } else { targetContent.slideUp(300); $(this).html('[+]'); } return false; }; var ser = function (s) { serial = $.SortSerialize(s); alert(serial.hash); }; which is the "standard" interface demo, PLUS How do I then get to read that cookie so that when I next visit the page the order is as I set it in the cookie? Hopefully from that I can work out the rest .......? Thanks for help in advance.

    Read the article

  • invasive vs non-invasive ref-counted pointers in C++

    - by anon
    For the past few years, I've generally accepted that if I am going to use ref-counted smart pointers invasive smart pointers is the way to go -- However, I'm starting to like non-invasive smart pointers due to the following: I only use smart pointers (so no Foo* lying around, only Ptr) I'm starting to build custom allocators for each class. (So Foo would overload operator new). Now, if Foo has a list of all Ptr (as it easily can with non-invasive smart pointers). Then, I can avoid memory fragmentation issues since class Foo move the objects around (and just update the corresponding Ptr). The only reason why this Foo moving objects around in non-invasive smart pointers being easier than invasive smart pointers is: In non-invasive smart pointers, there is only one pointer that points to each Foo. In invasive smart pointers, I have no idea how many objects point to each Foo. Now, the only cost of non-invasive smart pointers ... is the double indirection. [Perhaps this screws up the caches]. Does anyone have a good study of expensive this extra layer of indirection is?

    Read the article

  • Can some tell me why I am seg faulting in this simple C program?

    - by user299648
    I keep on getting seg faulted after I end my first for loop, and for the life of me I don't why. The file I'm scanning is just 18 strings in 18 lines. I thinks the problem is the way I'm mallocing the double pointer called picks, but I don't know exactly why. I'm am only trying to scanf strings that are less than 15 chars long, so I don't see the problem. Can someone please help. #include <stdio.h> #include <stdlib.h> #include <string.h> #define MAX_LENGTH 100 int main( int argc,char *argv[] ) { char* string = malloc( 15*sizeof(char) ); char** picks = malloc(15*sizeof(char*)); FILE* pick_file = fopen( argv[l], "r" ); int num_picks; for( num_picks=0 ; fgets( string, MAX_LENGTH, pick_file ) != NULL ; num_picks++ ) { scanf( "%s", picks+num_picks ); } //this is where i seg fault int x; for(x=0; x<num_picks;x++) printf("s\n", picks+x); }

    Read the article

  • How can I modified the value of a string defined in a struc?

    - by Eric
    Hi, I have the following code in c++: define TAM 4000 define NUMPAGS 512 struct pagina { bitset<12 direccion; char operacion; char permiso; string *dato; int numero; }; void crearPagina(pagina* pag[], int pos, int dir) { pagina * paginas = (pagina*)malloc(sizeof(char) * TAM); paginas - direccion = bitset<12 (dir); paginas - operacion = 'n'; paginas - permiso = 'n'; string **tempDato = &paginas - dato; char *temp = " "; **tempDato = temp; paginas - numero = 0; pag[pos] = paginas; } I want to modify the value of the variable called "string *dato" in the struct pagina but, everytime I want to assing a new value, the compiler throws a segmentation fault. In this case I'm using a pointer to string, but I have also tried with a string. In a few words I want to do the following: pagina - dato = "test"; Any idea? Thanks in advance!!!

    Read the article

  • Merge DataGrid ColumnHeaders

    - by Vishal
    I would like to merge two column-Headers. Before you go and mark this question as duplicate please read further. I don't want a super-Header. I just want to merge two column-headers. Take a look at image below: Can you see two columns with headers Mobile Number 1 and Mobile Number 2? I want to show there only 1 column header as Mobile Numbers. Here is the XAML used for creating above mentioned dataGrid: <DataGrid Grid.Row="1" Margin="0,10,0,0" ItemsSource="{Binding Ledgers}" IsReadOnly="True" AutoGenerateColumns="False"> <DataGrid.Columns> <DataGridTextColumn Header="Customer Name" Binding="{Binding LedgerName}" /> <DataGridTextColumn Header="City" Binding="{Binding City}" /> <DataGridTextColumn Header="Mobile Number 1" Binding="{Binding MobileNo1}" /> <DataGridTextColumn Header="Mobile Number 2" Binding="{Binding MobileNo2}" /> <DataGridTextColumn Header="Opening Balance" Binding="{Binding OpeningBalance}" /> </DataGrid.Columns> </DataGrid> Update1: Update2 I have created a converter as follows: public class MobileNumberFormatConverter : IValueConverter { public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { if (value != null && value != DependencyProperty.UnsetValue) { if (value.ToString().Length <= 15) { int spacesToAdd = 15 - value.ToString().Length; string s = value.ToString().PadRight(value.ToString().Length + spacesToAdd); return s; } return value.ToString().Substring(0, value.ToString().Length - 3) + "..."; } return ""; } public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { throw new NotImplementedException(); } } I have used it in XAML as follows: <DataGridTextColumn Header="Mobile Numbers"> <DataGridTextColumn.Binding> <MultiBinding StringFormat=" {0} {1}"> <Binding Path="MobileNo1" Converter="{StaticResource mobileNumberFormatConverter}"/> <Binding Path="MobileNo2" Converter="{StaticResource mobileNumberFormatConverter}"/> </MultiBinding> </DataGridTextColumn.Binding> </DataGridTextColumn> The output I got: Update3: At last I got the desired output. Here is the code for Converter: public class MobileNumberFormatConverter : IValueConverter { public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { if (value != null && value != DependencyProperty.UnsetValue) { if (parameter.ToString().ToUpper() == "N") { if (value.ToString().Length <= 15) { return value.ToString(); } else { return value.ToString().Substring(0, 12); } } else if (parameter.ToString().ToUpper() == "S") { if (value.ToString().Length <= 15) { int spacesToAdd = 15 - value.ToString().Length; string spaces = ""; return spaces.PadRight(spacesToAdd); } else { return "..."; } } } return ""; } public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { throw new NotImplementedException(); } } Here is my XAML: <DataGridTemplateColumn Header="Mobile Numbers"> <DataGridTemplateColumn.CellTemplate> <DataTemplate> <TextBlock> <Run Text="{Binding MobileNo1, Converter={StaticResource mobileNumberFormatConverter}, ConverterParameter=N}" /> <Run Text="{Binding MobileNo1, Converter={StaticResource mobileNumberFormatConverter}, ConverterParameter=S}" FontFamily="Consolas"/> <Run Text=" " FontFamily="Consolas"/> <Run Text="{Binding MobileNo2, Converter={StaticResource mobileNumberFormatConverter}, ConverterParameter=N}" /> <Run Text="{Binding MobileNo2, Converter={StaticResource mobileNumberFormatConverter}, ConverterParameter=S}" FontFamily="Consolas"/> </TextBlock> </DataTemplate> </DataGridTemplateColumn.CellTemplate> </DataGridTemplateColumn> Output:

    Read the article

  • Reading serialised object from file

    - by nico
    Hi everyone. I'm writing a little Java program (it's an ImageJ plugin, but the problem is not specifically ImageJ related) and I have some problem, most probably due to the fact that I never really programmed in Java before... So, I have a Vector of Vectors and I'm trying to save it to a file and read it. The variable is defined as: Vector <Vector <myROI> > ROIs = new Vector <Vector <myROI> >(); where myROI is a class that I previously defined. Now, to write the vector to a file I use: void saveROIs() { SaveDialog save = new SaveDialog("Save ROIs...", imp.getTitle(), ".xroi"); String name = save.getFileName(); if (name == null) return; String dir = save.getDirectory(); try { FileOutputStream fos = new FileOutputStream(dir+name); ObjectOutputStream oos = new ObjectOutputStream(fos); oos.writeObject(ROIs); oos.close(); } catch (Exception e) { IJ.log(e.toString()); } } This correctly generates a binary file containing (I suppose) the object ROIs. Now, I use a very similar code to read the file: void loadROIs() { OpenDialog open = new OpenDialog("Load ROIs...", imp.getTitle(), ".xroi"); String name = open.getFileName(); if (name == null) return; String dir = open.getDirectory(); try { FileInputStream fin = new FileInputStream(dir+name); ObjectInputStream ois = new ObjectInputStream(fin); ROIs = (Vector <Vector <myROI> >) ois.readObject(); // This gives error ois.close(); } catch (Exception e) { IJ.log(e.toString()); } } But this function does not work. First, I get a warning: warning: [unchecked] unchecked cast found : java.lang.Object required: java.util.Vector<java.util.Vector<myROI>> ROIs = (Vector <Vector <myROI> >) ois.readObject(); ^ I Googled for that and see that I can suppress by prepending @SuppressWarnings("unchecked"), but this just makes things worst, as I get an error: <identifier> expected ROIs = (Vector <Vector <myROI> >) ois.readObject(); ^ In any case, if I omit @SuppressWarnings and ignore the warning, the object is not read and an exception is thrown java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: myROI Again Google tells me myROI needs to implements Serializable. I tried just adding implements Serializable to the class definition, but it is not sufficient. Can anyone give me some hints on how to procede in this case? Also, how to get rid of the typecast warning?

    Read the article

  • Is there a general-purpose printf-ish routine defined in any C standard

    - by supercat
    In many C libraries, there is a printf-style routine which is something like the following: int __vgprintf(void *info, (void)(*print_function(void*, char)), const char *format, va_list params); which will format the supplied string and call print_function with the passed-in info value and each character in sequence. A function like fprintf will pass __vgprintf the passed-in file parameter and a pointer to a function which will cast its void* to a FILE* and output the passed-in character to that file. A function like snprintf will create a struct holding a char* and length, and pass the address of that struct to a function which will output each character in sequence, space permitting. Is there any standard for such a function, which could be used if e.g. one wanted a function to output an arbitrary format to a TCP port? A common approach is to allocate a buffer one hopes is big enough, use snprintf to put the data there, and then output the data from the buffer. It would seem cleaner, though, if there were a standard way to to specify that the print formatter should call a user-supplied routine with each character.

    Read the article

  • Inheritance inside a template - public members become invisible?

    - by Juliano
    I'm trying to use inheritance among classes defined inside a class template (inner classes). However, the compiler (GCC) is refusing to give me access to public members in the base class. Example code: template <int D> struct Space { struct Plane { Plane(Space& b); virtual int& at(int y, int z) = 0; Space& space; /* <= this member is public */ }; struct PlaneX: public Plane { /* using Plane::space; */ PlaneX(Space& b, int x); int& at(int y, int z); const int cx; }; int& at(int x, int y, int z); }; template <int D> int& Space<D>::PlaneX::at(int y, int z) { return space.at(cx, y, z); /* <= but it fails here */ }; Space<4> sp4; The compiler says: file.cpp: In member function ‘int& Space::PlaneX::at(int, int)’: file.cpp:21: error: ‘space’ was not declared in this scope If using Plane::space; is added to the definition of class PlaneX, or if the base class member is accessed through the this pointer, or if class Space is changed to a non-template class, then the compiler is fine with it. I don't know if this is either some obscure restriction of C++, or a bug in GCC (GCC versions 4.4.1 and 4.4.3 tested). Does anyone have an idea?

    Read the article

< Previous Page | 529 530 531 532 533 534 535 536 537 538 539 540  | Next Page >