Search Results

Search found 21759 results on 871 pages for 'int 0'.

Page 479/871 | < Previous Page | 475 476 477 478 479 480 481 482 483 484 485 486  | Next Page >

• select failing with C program but not shell

  - by Gary

  So I have a parent and child process, and the parent can read output from the child and send to the input of the child. So far, everything has been working fine with shell scripts, testing commands which input and output data. I just tested with a simple C program and couldn't get it to work. Here's the C program: #include <stdio.h> int main( void ) { char stuff[80]; printf("Enter some stuff:\n"); scanf("%s", stuff); return 0; } The problem with with the C program is that my select fails to read from the child fd and hence the program cannot finish. Here's the bit that does the select.. //wait till child is ready fd_set set; struct timeval timeout; FD_ZERO( &set ); // initialize fd set FD_SET( PARENT_READ, &set ); // add child in to set timeout.tv_sec = 3; timeout.tv_usec = 0; int r = select(FD_SETSIZE, &set, NULL, NULL, &timeout); if( r < 1 ) { // we didn't get any input exit(1); } Does anyone have any idea why this would happen with the C program and not a shell one? Thanks!

  Read the article

• Socket.Recieve Failing When Multithreaded

  - by Qua

  The following piece of code runs fine when parallelized to 4-5 threads, but starts to fail as the number of threads increase somewhere beyond 10 concurrentthreads int totalRecieved = 0; int recieved; StringBuilder contentSB = new StringBuilder(4000); while ((recieved = socket.Receive(buffer, SocketFlags.None)) > 0) { contentSB.Append(Encoding.ASCII.GetString(buffer, 0, recieved)); totalRecieved += recieved; } The Recieve method returns with zero bytes read, and if I continue calling the recieve method then I eventually get a 'An established connection was aborted by the software in your host machine'-exception. So I'm assuming that the host actually sent data and then closed the connection, but for some reason I never recieved it. I'm curious as to why this problem arises when there are a lot of threads. I'm thinking it must have something to do with the fact that each thread doesn't get as much execution time and therefore there are some idle time for the threads which causes this error. Just can't figure out why idle time would cause the socket not to recieve any data.

  Read the article

• Arduino variable going blank after the first pass

  - by user541597

  I have an Arduino sketch that takes a timet and when that timet is equal to the current time it sets the new timet to timet + 2. For example: char* convert(char* x, String y) { int hour; int minute; sscanf(x, "%d:%d", &hour, &minute); char buf[6]; if (y == "6") { if (hour > 17) { hour = (hour+6)%24; snprintf(buf, 10, "%d:%d", hour, minute ); } else if (hour < 18) { //hour = hour + 6; minute = (minute + 2); snprintf(buf, 10, "%d:%d", hour, minute); } } if (y == "12") { if (hour > 11) { hour = (hour+12)%24; snprintf(buf, 10, "%d:%d", hour, minute ); } else if (hour < 12) { hour = hour + 12; snprintf(buf, 10, "%d:%d", hour, minute); } } if (y == "24") { hour = (hour+24)%24; snprintf(buf, 10, "%d:%d", hour, minute ); } return buf; } The sketch starts for example at 1:00am. timet is set to 1:02, at system time 1:02 timet is equal to the system time. My loops looks like this: if (timet == currenttime) { timet = convert(timet) } Whenever I check the value of timet it should equal 1:04, however I get the correct value at the first run after the execution of convert, however every time after that my timet value is blank. I tried changing the code instead of using the if loop. I only run the convert function when I send for example t through the serial monitor. This works fine and outputs the correct timet after the execution of the convert function, So I figured the problem is in the if loop... Any ideas?

  Read the article

• Few Basic Questions in Overriding

  - by Dahlia

  I have few problems with my basic and would be thankful if someone can clear this. What does it mean when I say base *b = new derived; Why would one go for this? We very well separately can create objects for class base and class derived and then call the functions accordingly. I know that this base *b = new derived; is called as Object Slicing but why and when would one go for this? I know why it is not advisable to convert the base class object to derived class object (because base class is not aware of the derived class members and methods). I even read in other StackOverflow threads that if this is gonna be the case then we have to change/re-visit our design. I understand all that, however, I am just curious, Is there any way to do this? class base { public: void f(){cout << "In Base";} }; class derived:public base { public: void f(){cout << "In Derived";} }; int _tmain(int argc, _TCHAR* argv[]) { base b1, b2; derived d1, d2; b2 = d1; d2 = reinterpret_cast<derived*>(b1); //gives error C2440 b1.f(); // Prints In Base d1.f(); // Prints In Derived b2.f(); // Prints In Base d1.base::f(); //Prints In Base d2.f(); getch(); return 0; } In case of my above example, is there any way I could call the base class f() using derived class object? I used d1.base()::f() I just want to know if there any way without using scope resolution operator? Thanks a lot for your time in helping me out!

  Read the article

• Making it look like the computer is thinking in TicTacToe game

  - by rage

  here is a slice of code that i've written in VB.net Private Sub L00_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles L00.Click, L01.Click, L02.Click, L03.Click, L10.Click, L11.Click, L12.Click, L13.Click, L20.Click, L21.Click, L22.Click, L23.Click, L30.Click, L31.Click, L32.Click, L33.Click Dim ticTac As Label = CType(sender, Label) Dim strRow As String Dim strCol As String 'Once a move is made, do not allow user to change whether player/computer goes first, because it doesn't make sense to do so since the game has already started. ComputerFirstStripMenuItem.Enabled = False PlayerFirstToolStripMenuItem.Enabled = False 'Check to make sure clicked tile is a valid tile i.e and empty tile. If (ticTac.Text = String.Empty) Then ticTac.Text = "X" ticTac.ForeColor = ColorDialog1.Color ticTac.Tag = 1 'After the player has made his move it becomes the computers turn. computerTurn(sender, e) Else MessageBox.Show("Please pick an empty tile to make next move", "Invalid Move") End If End Sub Private Sub computerTurn(ByVal sender As System.Object, ByVal e As System.EventArgs) Call Randomize() row = Int(4 * Rnd()) col = Int(4 * Rnd()) 'Check to make sure clicked tile is a valid tile i.e and empty tile. If Not ticTacArray(row, col).Tag = 1 And Not ticTacArray(row, col).Tag = 4 Then ticTacArray(row, col).Text = "O" ticTacArray(row, col).ForeColor = ColorDialog2.Color ticTacArray(row, col).Tag = 4 checkIfGameOver(sender, e) Else 'Some good ole pseudo-recursion(doesn't require a base case(s)). computerTurn(sender, e) End If End Sub Everything works smoothly, except i'm trying to make it seem like the computer has to "think" before making its move. So what i've tried to do is place a System.Threading.Sleep() call in different places in the code above. The problem is that instead of making the computer look like its thinking, the program waits and then puts the X and O together at the same time. Can someone help me make it so that the program puts an X wherever i click AND THEN wait before it places an O? Edit: in case any of you are wondering, i realize that the computers AI is ridiculously dumb, but its just to mess around right now. Later on i will implement a serious AI..hopefully.

  Read the article

• Hibernate: Walk millions of rows and don't leak memory

  - by Autocracy

  The below code functions, but Hibernate never lets go of its grip of any object. Calling session.clear() causes exceptions regarding fetching a joined class, and calling session.evict(currentObject) before retrieving the next object also fails to free the memory. Eventually I exhaust my heap space. Checking my heap dumps, StatefulPersistenceContext is the garbage collector's root for all references pointing to my objects. public class CriteriaReportSource implements JRDataSource { private ScrollableResults sr; private Object currentObject; private Criteria c; private static final int scrollSize = 10; private int offset = 1; public CriteriaReportSource(Criteria c) { this.c = c; advanceScroll(); } private void advanceScroll() { // ((Session) Main.em.getDelegate()).clear(); this.sr = c.setFirstResult(offset) .setMaxResults(scrollSize) .scroll(ScrollMode.FORWARD_ONLY); offset += scrollSize; } public boolean next() { if (sr.next()) { currentObject = sr.get(0); if (sr.isLast()) { advanceScroll(); } return true; } return false; } public Object getFieldValue(JRField jrf) throws JRException { Object retVal = null; if(currentObject == null) { return null; } try { retVal = PropertyUtils.getProperty(currentObject, jrf.getName()); } catch (Exception ex) { Logger.getLogger(CriteriaReportSource.class.getName()).log(Level.SEVERE, null, ex); } return retVal; } }

  Read the article

• Using an ORM with a database that has no defined relationships?

  - by Ahmad

  Consider a database(MSSQL 2005) that consists of 100+ tables which have primary keys defined to a certain degree. There are 'relationships' between tables, however these are not enforced with foreign key constraints. Consider the following simplified example of typical types of tables I am dealing with. The are clear relations between the User and City and Province tables. However, they key issues is the inconsistent data types in the tables and naming conventions. User: UserRowId [int] PK Name [varchar(50)] CityId [smallint] ProvinceRowId [bigint] City: CityRowId [bigint] PK CityDescription [varchar(100)] Province: ProvinceId [int] PK ProvinceDesc [varchar(50)] I am considering a rewrite of the application (in ASP.net MVC) that uses this data source as is similar in design to MVC storefront. However I am going through a proof of concept phase and this is one of the stumbling blocks I have come across. What are my options in terms of ORM choice that can be easily used and why? Should I even be considering an ORM? (The reason I ask this is that most explanations and tutorials all work with relatively cleanly designed existing databases, or newly created ones when compared to mine. I am thus having a very hard time trying to find a way forward with this problem) There is a huge amount of existing SQL queries, would a datamappper(eg IBatis.net) be more suitable since we could easily modify them to work and reuse the investment already made? I have found this question on SO which indicates to me that an ORM can be used - however I get the impression that this a question of mapping? Note: at the moment, the object model is not clearly defined as it was non-existent. The existing system pretty much did almost everything in SQL or consisted of overly complicated, and numerous queries to complete fucntionality. I am pretty much a noob and have zero experience around ORMs and MVC - so this an awesome learning curve I am on.

  Read the article

• Inject runtime exception to pthread sometime fails. How to fix that?

  - by lionbest

  I try to inject the exception to thread using signals, but some times the exception is not get caught. For example the following code: void _sigthrow(int sig) { throw runtime_error(strsignal(sig)); } struct sigaction sigthrow = {{&_sigthrow}}; void* thread1(void*) { sigaction(SIGINT,&sigthrow,NULL); try { while(1) usleep(1); } catch(exception &e) { cerr << "Thread1 catched " << e.what() << endl; } }; void* thread2(void*) { sigaction(SIGINT,&sigthrow,NULL); try { while(1); } catch(exception &e) { cerr << "Thread2 catched " << e.what() << endl; //never goes here } }; If I try to execute like: int main() { pthread_t p1,p2; pthread_create( &p1, NULL, &thread1, NULL ); pthread_create( &p2, NULL, &thread2, NULL ); sleep(1); pthread_kill( p1, SIGINT); pthread_kill( p2, SIGINT); sleep(1); return EXIT_SUCCESS; } I get the following output: Thread1 catched Interrupt terminate called after throwing an instance of 'std::runtime_error' what(): Interrupt Aborted How can I make second threat catch exception? Is there better idea about injecting exceptions?

  Read the article

• How do I post a .wav file from CS5 Flash, AS3 to a Java servlet?

  - by Muostar

  Hi, I am trying to send a byteArray from my .fla to my running tomcat server integrated in Eclipse. From flash I am using the following code: var loader:URLLoader = new URLLoader(); var header:URLRequestHeader = new URLRequestHeader("audio/wav", "application/octet-stream"); var request:URLRequest = new URLRequest("http://localhost:8080/pdp/Server?wav=" + tableID); request.requestHeaders.push(header); request.method = URLRequestMethod.POST; request.data = file;//wav; loader.load(request); And my java servlet looks as follows: try{ int readBytes = -1; int lengthOfBuffer = request.getContentLength(); InputStream input = request.getInputStream(); byte[] buffer = new byte[lengthOfBuffer]; ByteArrayOutputStream output = new ByteArrayOutputStream(lengthOfBuffer); while((readBytes = input.read(buffer, 0, lengthOfBuffer)) != -1) { output.write(buffer, 0, readBytes); } byte[] finalOutput = output.toByteArray(); input.close(); FileOutputStream fos = new FileOutputStream(getServletContext().getRealPath(""+"/temp/"+wav+".wav")); fos.write(finalOutput); fos.close(); When i run the flash .swf file and send the bytearray to the server, I receive following in the server's console window:: (loads of loads of Chinese symbols) May 20, 2010 7:04:57 PM org.apache.tomcat.util.http.Parameters processParameters WARNING: Parameters: Character decoding failed. Parameter '? (loads of loads of Chinese symbols) and then looping this for a long time. It is like I recieve the bytes but not encoding/decoding them correctly. What can I do?

  Read the article

• What would be different in Java if Enum declaration didn't have the recursive part

  - by atamur

  Please see http://stackoverflow.com/questions/211143/java-enum-definition and http://stackoverflow.com/questions/3061759/why-in-java-enum-is-declared-as-enume-extends-enume for general discussion. Here I would like to learn what exactly would be broken (not typesafe anymore, or requiring additional casts etc) if Enum class was defined as public class Enum<E extends Enum> I'm using this code for testing my ideas: interface MyComparable<T> { int myCompare(T o); } class MyEnum<E extends MyEnum> implements MyComparable<E> { public int myCompare(E o) { return -1; } } class FirstEnum extends MyEnum<FirstEnum> {} class SecondEnum extends MyEnum<SecondEnum> {} With it I wasn't able to find any benefits in this exact case. PS. the fact that I'm not allowed to do class ThirdEnum extends MyEnum<SecondEnum> {} when MyEnum is defined with recursion is a) not relevant, because with real enums you are not allowed to do that just because you can't extend enum yourself b) not true - pls try it in a compiler and see that it in fact is able to compile w/o any errors PPS. I'm more and more inclined to believe that the correct answer here would be "nothing would change if you remove the recursive part" - but I just can't believe that.

  Read the article

• Incorrect logic flow? function that gets coordinates for a sudoku game

  - by igor

  This function of mine keeps on failing an autograder, I am trying to figure out if there is a problem with its logic flow? Any thoughts? Basically, if the row is wrong, "invalid row" should be printed, and clearInput(); called, and return false. When y is wrong, "invalid column" printed, and clearInput(); called and return false. When both are wrong, only "invalid row" is to be printed (and still clearInput and return false. Obviously when row and y are correct, print no error and return true. My function gets through most of the test cases, but fails towards the end, I'm a little lost as to why. bool getCoords(int & x, int & y) { char row; bool noError=true; cin>>row>>y; row=toupper(row); if(row>='A' && row<='I' && isalpha(row) && y>=1 && y<=9) { x=row-'A'; y=y-1; return true; } else if(!(row>='A' && row<='I')) { cout<<"Invalid row"<<endl; noError=false; clearInput(); return false; } else { if(noError) { cout<<"Invalid column"<<endl; } clearInput(); return false; } }

  Read the article

• Sending files from server to client in Java

  - by Lee Jacobson

  Hi, I'm trying to find a way to send files of different file types from a server to a client. I have this code on the server to put the file into a byte array: File file = new File(resourceLocation); byte[] b = new byte[(int) file.length()]; FileInputStream fileInputStream; try { fileInputStream = new FileInputStream(file); try { fileInputStream.read(b); } catch (IOException ex) { System.out.println("Error, Can't read from file"); } for (int i = 0; i < b.length; i++) { fileData += (char)b[i]; } } catch (FileNotFoundException e) { System.out.println("Error, File Not Found."); } I then send fileData as a string to the client. This works fine for txt files but when it comes to images I find that although it creates the file fine with the data in, the image won't open. I'm not sure if I'm even going about this the right way. Thanks for the help.

  Read the article

• How to create a list/structure? in JAVA

  - by lox

  i have to create a list of ,let's say 50 people, (in JAVA) and display the list, and i don't really know how to do that. so this is what i have tried to do so far . please correct and complete some of my code . public class Person { String name; String stuff; } public class CreatePerson { public static void ang() { ArrayList<Person> thing=new ArrayList<Person>(); Scanner diskScanner = new Scanner(in); for(int i=0; i<50; i++){ Person pers = new Person(); out.print("name: "); pers.name=diskScanner.nextLine(); out.print("stuff: "); pers.stuff=diskScanner.nextLine(); thing.add(pers); break; } // Display people for (int i=0; i<50; i++) { out.println(??);{ } } }}

  Read the article

• Strange inheritance behaviour in Objective-C

  - by Smikey

  Hi all, I've created a class called SelectableObject like so: #define kNumberKey @"Object" #define kNameKey @"Name" #define kThumbStringKey @"Thumb" #define kMainStringKey @"Main" #import <Foundation/Foundation.h> @interface SelectableObject : NSObject <NSCoding> { int number; NSString *name; NSString *thumbString; NSString *mainString; } @property (nonatomic, assign) int number; @property (nonatomic, retain) NSString *name; @property (nonatomic, retain) NSString *thumbString; @property (nonatomic, retain) NSString *mainString; @end So far so good. And the implementation section conforms to the NSCoding protocol as expected. HOWEVER, when I add a new class which inherits from this class, i.e. #import <Foundation/Foundation.h> #import "SelectableObject.h" @interface Pet : SelectableObject <NSCoding> { } @end I suddenly get the following compiler error in the Selectable object class! SelectableObject.h:16: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'interface' This makes no sense to me. Why is the interface declaration for the SelectableObject class suddenly broken? I also import it in a couple of other classes I've written... Any help would be very much appreciated. Thanks! Michael

  Read the article

• Rotating an ImageVIew along with its original position in android in below HoneyComb versions

  - by candy

  I am trying rotate an ImageView along with its original location (rotating the image aswell as the view). So that After rotation, when I click on the rotated Image in its current position, it should be able clicked in the rotated location only. For this solution I am trying the following code. However it is rotating is going fine. After the rotation end I need to place the ImageView and Image in the rotated Location to make it able click over there only. But it is not going successfully. I am unable to rotated Image location axis points to place correctly. Can any one please suggest a way to resolve this issue. fyi-It should work on Gingerbread version android-9 aniView1.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Log.e("", "Clicked on IMAGE VIEW - 1"); } }); RotateAnimation rotate5 = new RotateAnimation(0, 150, Animation.INFINITE, 100, Animation.INFINITE, 250); //rotate5.setFillAfter(true); rotate5.setDuration(2000); rotate5.setInterpolator(new LinearInterpolator()); aniView1.setAnimation(rotate5); rotate5.setAnimationListener(new Animation.AnimationListener() { @Override public void onAnimationStart(Animation animation) { } @Override public void onAnimationRepeat(Animation animation) { } @Override public void onAnimationEnd(Animation animation) { int newTop = (int) (aniView1.getTop() + aniView1.getWidth()); aniView1.layout(aniView1.getLeft()-200, newTop, aniView1.getRight(), aniView1.getBottom() + aniView1.getMeasuredWidth()); // aniView1.setLayoutParams(new // RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT,RelativeLayout.LayoutParams.WRAP_CONTENT)); } });

  Read the article

• java gregorian calendar timer

  - by Ieyasu Sawada

  I have this java program which calculates the time that the person took to respond to the confirm dialog box. But it seems that both time1 and time 2 gets the same value. What have I done wrong here: import javax.swing.JOptionPane; import java.util.*; public class DialogTimer{ public static void main(String args[]){ int time1, time2, milli1, milli2, sec1, sec2, timeDifference; final int MILLISECSINSECOND =1000; JOptionPane.showConfirmDialog(null, "Is stealing ever justified? "); GregorianCalendar before=new GregorianCalendar(); GregorianCalendar after= new GregorianCalendar(); milli1=before.get(GregorianCalendar.MILLISECOND); milli2=after.get(GregorianCalendar.MILLISECOND); sec1=before.get(GregorianCalendar.SECOND); sec2=after.get(GregorianCalendar.SECOND); time1=MILLISECSINSECOND * sec1 + milli1; time2=MILLISECSINSECOND * sec2 + milli2; //timeDifference=time1 - time2; System.out.println(time1); System.out.println(time2); //JOptionPane.showMessageDialog(null, "It took " + (time1 - time2) + " milliseconds for you to answer"); } }

  Read the article

• Getting value from pointer

  - by Eric

  Hi, I'm having problem getting the value from a pointer. I have the following code in C++: void* Nodo::readArray(VarHash& var, string varName, int posicion, float& d) { //some code before... void* res; float num = bit.getFloatFromArray(arregloTemp); //THIS FUNCTION RETURN A FLOAT AND IT'S OK cout << "NUMBER " << num << endl; d = num; res = &num; return res } int main() { float d = 0.0; void* res = n.readArray(v, "c", 0, d); //THE VALUES OF THE ARRAY ARE: {65.5, 66.5}; float* car3 = (float*)res; cout << "RESULT_READARRAY " << *car3 << endl; cout << "FLOAT REFERENCE: " << d << endl; } The result of running this code is the following: NUMBER 65.5 RESULT_READARRAY -1.2001 //INCORRECT IT SHOULD BE LIKE NUMBER FLOAT REFERENCE: 65.5 //CORRECT NUMBER 66.5 RESULT_READARRAY -1.2001 //INCORRECT IT SHOULD BE LIKE NUMBER FLOAT REFERENCE: 66.5 //CORRECT For some reason, when I get the value of the pointer returned by the function called readArray is incorrect. I'm passing a float variable(d) as a reference in the same function just to verify that the value is ok, and as you can see, THE FLOAT REFERENCE matches the NUMBER. If I declare the variable num(read array) as a static float, the first RESULT_READARRAY will be 65.5, that is correct, however, the next value will be the same instead of 66.5. Let me show you the result of running the code using static float variable: NUMBER 65.5 RESULT_READARRAY 65.5 //PERFECT FLOAT REFERENCE: 65.5 //¨PERFECT NUMBER 65.5 //THIS IS INCORRECT, IT SHOULD BE 66.5 RESULT_READARRAY 65.5 FLOAT REFERENCE: 65.5 Do you know how can I get the correct value returned by the function called readArray()?

  Read the article

• Factorial in Prolog and C++

  - by Joshua Green

  I would like to work out a number's factorial. My factorial rule is in a Prolog file and I am connecting it to a C++ code. Can someone tell me what is wrong with my C++ interface please? % factorial.pl factorial( 1, 1 ):- !. factorial( X, Fac ):- X > 1, Y is X - 1, factorial( Y, New_Fac ), Fac is X * New_Fac. // factorial.cpp # headerfiles term_t t1; term_t t2; term_t goal_term; functor_t goal_functor; int main( int argc, char** argv ) { argc = 4; argv[0] = "libpl.dll"; argv[1] = "-G32m"; argv[2] = "-L32m"; argv[3] = "-T32m"; PL_initialise(argc, argv); if ( !PL_initialise(argc, argv) ) PL_halt(1); PlCall( "consult(swi('plwin.rc'))" ); PlCall( "consult('factorial.pl')" ); cout << "Enter your factorial number: "; long n; cin >> n; PL_put_integer( t1, n ); t1 = PL_new_term_ref(); t2 = PL_new_term_ref(); goal_term = PL_new_term_ref(); goal_functor = PL_new_functor( PL_new_atom("factorial"), 2 ); PL_put_atom( t1, t2 ); PL_cons_functor( goal_term, goal_functor, t1, t2 ); PL_halt( PL_toplevel() ? 0 : 1 ); }

  Read the article

• linux raw socket programming question

  - by user194420

  Hi all, I am trying to create a raw socket which send and receive message with ip/tcp header under linux. I can successfully binds to a port and receive tcp message(ie:syn) However, the message seems to be handled by the os, but not mine. I am just a reader of it(like wireshark). My raw socket binds to port 8888, and then i try to telnet to that port . In wireshark, it shows that the port 8888 reply a "rst ack" when it receive the "syn" request. In my program, it shows that it receive a new message and it doesnot reply with any message. Any way to actually binds to that port?(prevent os handle it) Here is part of my code, i try to cut those error checking for easy reading sockfd = socket(AF_INET, SOCK_RAW, IPPROTO_TCP); int tmp = 1; const int *val = &tmp; setsockopt (sockfd, IPPROTO_IP, IP_HDRINCL, val, sizeof (tmp)); servaddr.sin_family = AF_INET; servaddr.sin_addr.s_addr = htonl(INADDR_ANY); servaddr.sin_port = htons(8888); bind(sockfd, (struct sockaddr*)&servaddr, sizeof(servaddr)); //call recv in loop

  Read the article

• Mutual class instances in C++

  - by SepiDev

  Hi guys. What is the issue with this code? Here we have two files: classA.h and classB.h classA.h: #ifndef _class_a_h_ #define _class_a_h_ #include "classB.h" class B; //???? class A { public: A() { ptr_b = new B(); //???? } virtual ~A() { if(ptr_b) delete ptr_b; //???? num_a = 0; } int num_a; B* ptr_b; //???? }; #endif //_class_a_h_ classB.h: #ifndef _class_b_h_ #define _class_b_h_ #include "classA.h" class A; //???? class B { public: B() { ptr_a = new A(); //???? num_b = 0; } virtual ~B() { if(ptr_a) delete ptr_a; //???? } int num_b; A* ptr_a; //???? }; #endif //_class_b_h_ when I try to compile it, the compiler (g++) says: classB.h: In constructor ‘B::B()’: classB.h:12: error: invalid use of incomplete type ‘struct A’ classB.h:6: error: forward declaration of ‘struct A’ classB.h: In destructor ‘virtual B::~B()’: classB.h:16: warning: possible problem detected in invocation of delete operator: classB.h:16: warning: invalid use of incomplete type ‘struct A’ classB.h:6: warning: forward declaration of ‘struct A’ classB.h:16: note: neither the destructor nor the class-specific operator delete will be called, even if they are declared when the class is defined.

  Read the article

• Why can I call a non-const member function pointer from a const method?

  - by sdg

  A co-worker asked about some code like this that originally had templates in it. I have removed the templates, but the core question remains: why does this compile OK? #include <iostream> class X { public: void foo() { std::cout << "Here\n"; } }; typedef void (X::*XFUNC)() ; class CX { public: explicit CX(X& t, XFUNC xF) : object(t), F(xF) {} void execute() const { (object.*F)(); } private: X& object; XFUNC F; }; int main(int argc, char* argv[]) { X x; const CX cx(x,&X::foo); cx.execute(); return 0; } Given that CX is a const object, and its member function execute is const, therefore inside CX::execute the this pointer is const. But I am able to call a non-const member function through a member function pointer. Are member function pointers a documented hole in the const-ness of the world? What (presumably obvious to others) issue have we missed?

  Read the article

• How to get mouseposition when context menu appears?

  - by ikky

  Hi. I have a panel which holds many pictureboxes. Each picturebox has registered "contextRightMenu" as their context menu. What i want when the context menu pops up is to get the current mouseposition. I have tried getting the mouseposition by using mouseDown and click, but these events happens after one of the items of the context menu is clicked, and that is too late. the popup event of the context menu does not deliver mouse event args, so i don't know how to get the mouseposition. If i can get mouse event args it is easy. Then i just can: this.contextRightClick.Popup += new System.EventHandler(this.contextRightClick_Popup); // If EventArgs include mouseposition within the sender private void contextRightClick_Popup)(object sender, EventArgs e) { int iLocationX = sender.Location.X; int iLocationY = sender.Location.Y; Point pPosition = new Point(iLocationX + e.X, iLocationY + e.Y); // Location + position within the sender = current mouseposition } Can anyone help me either get some mouse event args, or suggest a event that will run before the contextmenu pop ups? Thanks in advance

  Read the article

• Download dynaic file with GWT

  - by Maksim

  I have a GWT page where user enter data (start date, end date, etc.), then this data goes to the server via RPC call. On the server I want to generate Excel report with POI and let user save that file on their local machine. This is my test code to stream file back to the client but for some reason it does not know: public class ReportsServiceImpl extends RemoteServiceServlet implements ReportsService { public String myMethod(String s) { File f = new File("/excelTestFile.xls"); String filename = f.getName(); int length = 0; try { HttpServletResponse resp = getThreadLocalResponse(); ServletOutputStream op = resp.getOutputStream(); ServletContext context = getServletConfig().getServletContext(); resp.setContentType("application/octet-stream"); resp.setContentLength((int) f.length()); resp.setHeader("Content-Disposition", "attachment; filename*=\"utf-8''" + filename + ""); byte[] bbuf = new byte[1024]; DataInputStream in = new DataInputStream(new FileInputStream(f)); while ((in != null) && ((length = in.read(bbuf)) != -1)) { op.write(bbuf, 0, length); } in.close(); op.flush(); op.close(); } catch (Exception ex) { ex.printStackTrace(); } return "Server says: " + filename; } } I've red somewhere on internet that you can't do file stream with RPC and I have to use Servlet for that. Is there any example of how to use Servlet and how to call that servlet from ReportsServiceImpl

  Read the article

• Why SetMinimumSize sets the minimal heights but not width?

  - by Roman

  Here is my code: import javax.swing.*; import java.awt.*; public class PanelModel { public static void main(String[] args) { JFrame frame = new JFrame("Colored Trails"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JPanel mainPanel = new JPanel(); mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.Y_AXIS)); JPanel firstPanel = new JPanel(); firstPanel.setLayout(new GridLayout(4, 4)); firstPanel.setMaximumSize(new Dimension(4*100, 4*100)); firstPanel.setMinimumSize(new Dimension(4*100, 4*100)); JButton btn; for (int i=1; i<=4; i++) { for (int j=1; j<=4; j++) { btn = new JButton(); btn.setPreferredSize(new Dimension(100, 100)); firstPanel.add(btn); } } mainPanel.add(firstPanel); frame.add(mainPanel); frame.setSize(520,600); //frame.setMinimumSize(new Dimension(520,600)); frame.setVisible(true); } } When I increase the size of the window (by mouse) I see that my panel does not increase its size. It is the expected behavior (because I set the maximal size of the panel). However, when I decrease the size of the window, I see that width of the panel is decreased too (while the height is constant). So, the setMinimumSize works only partially. Why is that?

  Read the article

• SQL Server 2008 - Keyword search using table Join

  - by Aaron Wagner

  Ok, I created a Stored Procedure that, among other things, is searching 5 columns for a particular keyword. To accomplish this, I have the keywords parameter being split out by a function and returned as a table. Then I do a Left Join on that table, using a LIKE constraint. So, I had this working beautifully, and then all of the sudden it stops working. Now it is returning every row, instead of just the rows it needs. The other caveat, is that if the keyword parameter is empty, it should ignore it. Given what's below, is there A) a glaring mistake, or B) a more efficient way to approach this? Here is what I have currently: ALTER PROCEDURE [dbo].[usp_getOppsPaged] @startRowIndex int, @maximumRows int, @city varchar(100) = NULL, @state char(2) = NULL, @zip varchar(10) = NULL, @classification varchar(15) = NULL, @startDateMin date = NULL, @startDateMax date = NULL, @endDateMin date = NULL, @endDateMax date = NULL, @keywords varchar(400) = NULL AS BEGIN SET NOCOUNT ON; ;WITH Results_CTE AS ( SELECT opportunities.*, organizations.*, departments.dept_name, departments.dept_address, departments.dept_building_name, departments.dept_suite_num, departments.dept_city, departments.dept_state, departments.dept_zip, departments.dept_international_address, departments.dept_phone, departments.dept_website, departments.dept_gen_list, ROW_NUMBER() OVER (ORDER BY opp_id) AS RowNum FROM opportunities JOIN departments ON opportunities.dept_id = departments.dept_id JOIN organizations ON departments.org_id=organizations.org_id LEFT JOIN Split(',',@keywords) AS kw ON (title LIKE '%'+kw.s+'%' OR [description] LIKE '%'+kw.s+'%' OR tasks LIKE '%'+kw.s+'%' OR requirements LIKE '%'+kw.s+'%' OR comments LIKE '%'+kw.s+'%') WHERE ( (@city IS NOT NULL AND (city LIKE '%'+@city+'%' OR dept_city LIKE '%'+@city+'%' OR org_city LIKE '%'+@city+'%')) OR (@state IS NOT NULL AND ([state] = @state OR dept_state = @state OR org_state = @state)) OR (@zip IS NOT NULL AND (zip = @zip OR dept_zip = @zip OR org_zip = @zip)) OR (@classification IS NOT NULL AND (classification LIKE '%'+@classification+'%')) OR ((@startDateMin IS NOT NULL AND @startDateMax IS NOT NULL) AND ([start_date] BETWEEN @startDateMin AND @startDateMax)) OR ((@endDateMin IS NOT NULL AND @endDateMax IS NOT NULL) AND ([end_date] BETWEEN @endDateMin AND @endDateMax)) OR ( (@city IS NULL AND @state IS NULL AND @zip IS NULL AND @classification IS NULL AND @startDateMin IS NULL AND @startDateMax IS NULL AND @endDateMin IS NULL AND @endDateMin IS NULL) ) ) ) SELECT * FROM Results_CTE WHERE RowNum >= @startRowIndex AND RowNum < @startRowIndex + @maximumRows; END

  Read the article

< Previous Page | 475 476 477 478 479 480 481 482 483 484 485 486  | Next Page >