Search Results

Search found 44956 results on 1799 pages for 'type checking'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 605/1799 | < Previous Page | 601 602 603 604 605 606 607 608 609 610 611 612  | Next Page >

  • How can I ask Hibernate to create an index on a foreign key (JoinColumn)?

    - by Kent Chen
    Hi, This is my model. class User{ @CollectionOfElements @JoinTable(name = "user_type", joinColumns = @JoinColumn(name = "user_id")) @Column(name = "type", nullable = false) private List<String> types = new ArrayList<String>(); } You can imagin there would be a table called "user_type", which has two columns, one is "user_id", the other is "type". And when I use hbm2ddl to generate the ddls, I can have this table, along with the foreign key constraint on "user_id". However, there is no index of this for this column. And I need this index. How can I let hibernate to generate this index for me? Thank you!

    Read the article

  • What is the sense of "Feature Oriented Programming" (FOP) in C++, and would it make sense in Java an

    - by ivan_ivanovich_ivanoff
    Hello! Sadly, I can't remember where I read it, but... ...in C++ you can derive a class from a template parameter. Im pretty sure it was called Feature Oriented Programming (FOP) and meant to be somehow useful. It was something like: template <class T> class my_class : T { // some very useful stuff goes here ;) } My questions about this: What is the sense of such pattern? Since this it not possible in Java / C#, how this pattern is achieved in these languages? Can it be expected to be implemented in Java / C# one day? (Well, first Java would need to get rid of type erasure) EDIT: I'm really not talking about generics in Java / C# (where you can't derive a class from a generic type parameter)

    Read the article

  • Using template specialization in C++

    - by user550413
    How can I write a function using template specialization that has 2 different input types and an output type: template <class input1, class input2, class output> and return the sum of the 2 numbers (integers/doubles). However, if I get 2 integers I want to return an integer type but for any other combinations of integer and double I'll always return double. I am trying to do that without using directly the '+' operator but having the next functions instead: double add_double_double(double a, double b) {return (a+b);} double add_int_double(int a, double b) {return ((double)(a)+b);} int add_int_int(int a, int b) {return (a+b);}

    Read the article

  • C# Different class objects in one list

    - by jeah_wicer
    I have looked around some now to find a solution to this problem. I found several ways that could solve it but to be honest I didn't realize which of the ways that would be considered the "right" C# or OOP way of solving it. My goal is not only to solve the problems but also to develop a good set of code standards and I'm fairly sure there's a standard way to handle this problem. Let's say I have 2 types of printer hardwares with their respective classes and ways of communicating: PrinterType1, PrinterType2. I would also like to be able to later on add another type if neccessary. One step up in abstraction those have much in common. It should be possible to send a string to each one of them as an example. They both have variables in common and variables unique to each class. (One for instance communicates via COM-port and has such an object, while the other one communicates via TCP and has such an object). I would however like to just implement a List of all those printers and be able to go through the list and perform things as "Send(string message)" on all Printers regardless of type. I would also like to access variables like "PrinterList[0].Name" that are the same for both objects, however I would also at some places like to access data that is specific to the object itself (For instance in the settings window of the application where the COM-port name is set for one object and the IP/port number for another). So, in short something like: In common: Name Send() Specific to PrinterType1: Port Specific to PrinterType2: IP And I wish to, for instance, do Send() on all objects regardless of type and the number of objects present. I've read about polymorphism, Generics, interfaces and such, but I would like to know how this, in my eyes basic, problem typically would be dealt with in C# (and/or OOP in general). I actually did try to make a base class, but it didn't quite seem right to me. For instance I have no use of a "string Send(string Message)" function in the base class itself. So why would I define one there that needs to be overridden in the derived classes when I would never use the function in the base class ever in the first place? I'm really thankful for any answers. People around here seem very knowledgeable and this place has provided me with many solutions earlier. Now I finally have an account to answer and vote with too. EDIT: To additionally explain, I would also like to be able to access the objects of the actual printertype. For instance the Port variable in PrinterType1 which is a SerialPort object. I would like to access it like: PrinterList[0].Port.Open() and have access to the full range of functionality of the underlaying port. At the same time I would like to call generic functions that work in the same way for the different objects (but with different implementations): foreach (printer in Printers) printer.Send(message)

    Read the article

  • Why is this not a valid XML DTD? (Parameter entity and #PCDATA)

    - by user68759
    Hi, Using the DTD validator here, I am informed that the following DTD is invalid. <!ENTITY % text "(#PCDATA|L)*"> <!ELEMENT H (%text;)+> <!ELEMENT L (#PCDATA)> The error message is: "A '(' character or an element type is required within declaration of element type "H"." at line 2, column 22. Can anyone please point out why it is invalid? The error message is not exactly very friendly to me. Thanks.

    Read the article

  • Which one is better to have auto-implemented property with private setter or private field and property just getter?

    - by PLB
    My question may be a part of an old topic - "properties vs fields". I have situation where variable is read-only for outside class but needs to modified inside a class. I can approach it in 2 ways: First: private Type m_Field; public Type MyProperty { get { return m_Field; } } Second: public Type MyProperty { get; private set; } After reading several articles (that mostly covered benefits of using public properties instead of public fields) I did not get idea if the second method has some advantage over the first one but writing less code. I am interested which one will be better practice to use in projects (and why) or it's just a personal choice. Maybe this question does not belong to SO so I apologize in advance.

    Read the article

  • How to add types from external assembly to toolbox control? (WPF)

    - by Louis Rhys
    I am trying to do something like this in my WPF application: ToolboxControl ctrl = new ToolboxControl(); Assembly assembly = Assembly.LoadFile(file); var category = new ToolboxCategory(assembly.GetName().Name); foreach (Type t in assembly.GetTypes()) { var wrapper = new ToolboxItemWrapper(t, t.Name); category.Add(wrapper); } ctrl.Categories.Add(category); i.e. adding ToolboxItemWrappers for each type found in an assembly. However the last line throws the following exception (see image) All dependencies of the external assembly are also referenced in the main (WPF) application. So what's wrong here and how to fix it?

    Read the article

  • Cast vector<T> to vector<const T>

    - by user345386
    I have a member variable of type vector (where is T is a custom class, but it could be int as well.) I have a function from which I want to return a pointer to this vector, but I don't want the caller to be able to change the vector or it's items. So I want the return type to be const vector* None of the casting methods I tried worked. The compiler keeps complaining that T is not compatible with const T. Here's some code that demonstrates the gist of what I'm trying to do; vector<int> a; const vector<const int>* b = (const vector<const int>* ) (&a); This code doesn't compile for me. Thanks in advance!

    Read the article

  • Embed an HTML <form> within a larger <form>?

    - by MikeN
    I want to have an HTML form embedded in another form like so: <form id="form1"> <input name="val1"/> <form id="form2"> <input name="val2"/> <input type="button" name="Submit Form 2 ONLY"> </form> <input type="button" name="Submit Form 1 data including form 2"> </form> I need to submit the entirety of form1, but when I submit form2 I only want to submit the data in form2 (not everything in form1.) Will this work?

    Read the article

  • Javascript - Text Input Attributes

    - by bobrusha
    I need to create a form element <input disabled type="text" value="smth" /> which is disabled by default. It enables when onmouseover occures. onmouseover="this.disabled=false;" And is disabled by onmouseout onmouseout="this.disabled=true;" What I need is to check the following. If the <input> is focused then it shouldn't be disabled. And if the form element loses focus it disables. Please help me to complete the events. <input disabled type="text" value="smth" onmouseover="this.disabled=false;" onfocus="???" onblur="???" onmouseout="if(???){this.disabled=true;}" />

    Read the article

  • Is correct name enough to make it happen?

    - by Knowing me knowing you
    Guys, I've just dipped in to limits.h by MS. I tried to check what's the return type for max() fnc and to my surprise I see something like this: // TEMPLATE CLASS numeric_limits template<class _Ty> class numeric_limits : public _Num_base { // numeric limits for arbitrary type _Ty (say little or nothing) public: static _Ty (__CRTDECL min)() _THROW0() { // return minimum value return (_Ty(0)); } static _Ty (__CRTDECL max)() _THROW0() { // return maximum value return (_Ty(0));//EXACTLY THE SAME WHAT IN min<<------------------ } //... other stuff }; so how is it possiple that in both min and max return does exactly the same? So does it mean if I would write makeSanwich() return (_Ty(0)) it would make a sandwich for me? How is it possible that having this same code just fnc names different we are getting different results?

    Read the article

  • Handling a binary operation that makes sense only for part of a hierarchy.

    - by usersmarvin_
    I have a hierarchy, which I'll simplify greatly, of implementations of interface Value. Assume that I have two implementations, NumberValue, and StringValue. There is an average operation which only makes sense for NumberValue, with the signature NumberValue average(NumberValue numberValue){ ... } At some point after creating such variables and using them in various collections, I need to average a collection which I know is only of type NumberValue, there are three possible ways of doing this I think: Very complicated generic signatures which preserve the type info in compile time (what I'm doing now, and results in hard to maintain code) Moving the operation to the Value level, and: throwing an unsupportedOperationException for StringValue, and casting for NumberValue. Casting at the point where I know for sure that I have a NumberValue, using slightly less complicated generics to insure this. Does anybody have any better ideas, or a recommendation on oop best practices?

    Read the article

  • Python Class Variables Question

    - by zyq524
    I have some doubt about python's class variables. As my understanding, if I define a class variable, which is declared outside the init() function, this variable will create only once as a static variable in C++. This seems right for some python types, for instance, dict and list type, but for those base type, e.g. int,float, is not the same. For example: class A: dict1={} list1=list() int1=3 def add_stuff(self, k, v): self.dict1[k]=v self.list1.append(k) self.int1=k def print_stuff(self): print self.dict1,self.list1,self.int1 a1 = A() a1.add_stuff(1, 2) a1.print_stuff() a2=A() a2.print_stuff() The output is: {1: 2} [1] 1 {1: 2} [1] 3 I understand the results of dict1 and list1, but why does int1 behavior different?

    Read the article

  • Fedora: "Login Incorrect"

    - by darkblackcorner
    I've just set up a minimal install on my netbook (the default was too resource hungry, so I figured I'd customize the install and learn something about linux at the same time!) No problems logging in as root, but when I create a new user and try to login as them I just get the "Login incorrect" error. I'm certain the password is correct, though the secure log displays an authentication error. Am I missing a permission somewhere? useradd test usermod -p [pwd] test Shell is added automatically I think (checking password file says shell is /bin/bash) I've tried adding the user to the sudo-ers group usermod -a -G wheel which doesn't help. I've kept the password simple in order to rule out human error.

    Read the article

  • Access to Label value with Javascript

    - by streetparade
    I need to access to a value in a checkbox, the atribute value has content, so i need to place the id somewhere else i created a label, but i have not access to that value alert(check[i].label); // doesnt work where else can i place a value in checkbox. Please dont write that i can do this <input type='checkbox' id='bla' name='mybla' vlaue='myvalue'> Hy Where can i place some other values ? I tryed with this <input type='checkbox' id='bla' name='mybla' vlaue='myvalue' label='myothervalue'> Hy first i get all checkbox ect... and in the for loop i did this alert(check[i].label); // doesnt work How can i do that?

    Read the article

  • CSS file not getting downloaded in Visual Studio 2008 SP?

    - by theraneman
    Hi guys, This might sound a little wierd, but all of a sudden the CSS and Javascript files referenced in my master page are not being downloaded while the page is being rendered. I am working on a ASP.NET MVC project and things were all fine like half an hour ago! Here is what I have in head section of the master page, <link href="/Content/MyCSS.css" rel="stylesheet" type="text/css" /> <script src="/Scripts/jquery-1.3.2.min.js" type="text/javascript"></script> I can see the CSS class intellisense while designing pages. But in the page source I do not see these files being added. I can see the css being applied in the VS designer. I have tried restarting VS, restarting my machine too. Anyone else faced this situation before. I might go crazy now.

    Read the article

  • Passing derived objects in a constructure

    - by Clarence Klopfstein
    This is a bit of a convoluted question, hopefully I can make it clear. I am finding that this may not be possible, but am trying to see if anybody has a solution. I have four classes, two are core classes and two are those core classes extended: extUser Extends coreUser extSecurity Extends coreSecurity In the constructor for coreUser you have this: public coreUser(string id, ref coreSecurity cs) When trying to extend coreUser you would have this: public extUser(string id ref extSecurity es) : base(id, ref es) This fails because es is of type, extSecurity and the base class expects a type of coreSecurity. I've not found anyway to cast this to allow for me to override this base class in C#. In VB it works just fine. Ideas?

    Read the article

  • Insert an element to std::set using constructor

    - by Dave17
    is it possible to insert a new element to std::set like in case of std::list for example: //insert one element named "string" to sublist of mylist std::list< std::list<string> > mylist; mylist.push_back(std::list<string>(1, "string")); Now, mylist has one element of type std::string in its sub-list of type std::list. How can you do the same in if std::set is the sub-set of std::list my list i.e std::list<std::set <string>> mylist; if you can't then why not?

    Read the article

  • How to do interactive with the prompt this way in PHP?

    - by user198729
    C:\>mysql -uroot -padmin Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 6 Server version: 5.0.37-community-nt-log MySQL Community Edition (GPL) Type 'help;' or '\h' for help. Type '\c' to clear the buffer. mysql> show databases -> ; +--------------------+ | Database | +--------------------+ | information_schema | | attendance | | fusionchartsdb | | mysql | | sugarcrm | | test | +--------------------+ 6 rows in set (0.09 sec) mysql> use mysql; Database changed mysql> So I want to start a process by mysql -uroot -padmin,and in that process I want to run these statements: show databases use mysql insert xxx (..) values (..) How to do it in PHP?

    Read the article

  • HTML5 Search Input: No Background Image in Chrome?

    - by Jason
    I have been pulling my hair out trying to get Chrome to style my search input with a background image. Firefox has no problem, but I fear it's because it treats the input as a regular text input. Is this simply not possible? Try this as a demo: <input type="search" /> ?input[type="search"] { background: transparent url(http://google.com/intl/en_ALL/images/srpr/logo1w.png) no-repeat 0 0; }?????? If it worked correctly, it should put Google's logo (or part of it) as the background image for the "Search" input. But as you will see when you look at this in Chrome, it DOES NOT WORK. Any ideas, or is this just one of HTML5's quirks? :\

    Read the article

  • Collections in C#

    - by Oghenero
    am converting a vb.net component to c#, i get this error Using the generic type 'System.Collections.ObjectModel.Collection<T>' requires '1' type arguments This is what i did in VB.NET i had this Private _bufferCol As Collection i did this in c# private Collection _bufferCol = new Collection(); My declaration is using Microsoft.VisualBasi; using System.Collections; using System.Collections.Generic; using System.ComponentModel; using System.Collections.ObjectModel; Can any body help me please.

    Read the article

  • login not working when changing from mysql to mysqli

    - by user1438647
    I have a code below where it logs a teacher in by matching it's username and password in the database, if correct, then log in, if incorrect, then display a message. <?php session_start(); $username="xxx"; $password="xxx"; $database="mobile_app"; $link = mysqli_connect('localhost',$username,$password); mysqli_select_db($link, $database) or die( "Unable to select database"); foreach (array('teacherusername','teacherpassword') as $varname) { $$varname = (isset($_POST[$varname])) ? $_POST[$varname] : ''; } ?> <form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post" id="teachLoginForm"> <p>Username</p><p><input type="text" name="teacherusername" /></p> <!-- Enter Teacher Username--> <p>Password</p><p><input type="password" name="teacherpassword" /></p> <!-- Enter Teacher Password--> <p><input id="loginSubmit" type="submit" value="Login" name="submit" /></p> </form> <?php if (isset($_POST['submit'])) { $query = " SELECT * FROM Teacher t WHERE (t.TeacherUsername = '".mysqli_real_escape_string($teacherusername)."') AND (t.TeacherPassword = '".mysqli_real_escape_string($teacherpassword)."') "; $result = mysqli_query($link, $query); $num = mysqli_num_rows($result); $loged = false; while($row = mysqli_fetch_array($result)) { if ($_POST['teacherusername'] == ($row['TeacherUsername']) && $_POST['teacherpassword'] == ($row['TeacherPassword'])) { $loged = true; } $_SESSION['teacherforename'] = $row['TeacherForename']; $_SESSION['teachersurname'] = $row['TeacherSurname']; $_SESSION['teacherusername'] = $row['TeacherUsername']; } if ($loged == true){ header( 'Location: menu.php' ) ; }else{ echo "The Username or Password that you Entered is not Valid. Try Entering it Again."; } mysqli_close($link); } ?> Now the problem is that even if the teacher has entered in the correct username and password, it still doesn't let the teacher log in. When the code above was the old mysql() code, it worked fine as teacher was able to login when username and password match, but when trying to change the code into mysqli then it causes login to not work even though username and password match. What am I doing wrong?

    Read the article

  • haskell. words into binary numbers

    - by Katja
    I need to convert words into binary numbers. With a bit help of yours I got this blCo::String -> Integer blCo x = num2bin(lett2num x) blCo (x:xs) | x:xs = num2bin(lett2num x):blCo xs num2lett :: Int -> Char num2lett n | (n <= ord 'A') && (n <= ord 'Z') = chr(ord 'A'+ n - 1) | (n <= ord 'a') && (n <= ord 'Z') = chr(ord 'A'+ n - 1) num2bin :: Integer -> String num2bin n | n >= 0 = concatMap show (reverse ( n2b n)) | otherwise = error "num2bin: negative number" where n2b 0 = [] n2b n = n `mod` 2 : n2b (n `div` 2) he tells me a mistake.I dont undertsand it mistake: Couldn't match expected type `Char' against inferred type `String' In the first argument of `lett2num', namely `x' In the first argument of `num2bin', namely `(lett2num x)' In the expression: num2bin (lett2num x)

    Read the article

  • How to pass a const unsigned char * from c++ to c#

    - by tzup
    So I have a function in unmanaged c++ that gets called when some text happens to have "arrived": #using <MyParser.dll> ... void dump_body(const unsigned char *Body, int BodyLen) { // Need to pass the body to DumpBody, but as what type? ... lMyParser::Parser::DumpBody(???); } DumpBody is a function defined in a C# DLL that should take one parameter of type? Body holds an array of characters (text) of length BodyLen. There's obviously some marshalling to be done here but I have no idea how. Please help.

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 601 602 603 604 605 606 607 608 609 610 611 612  | Next Page >