Search Results

Search found 20887 results on 836 pages for 'instance fields'.

Page 170/836 | < Previous Page | 166 167 168 169 170 171 172 173 174 175 176 177  | Next Page >

  • Class constructor in java

    - by aladine
    Please advise me the difference between two ways of declaration of java constructor public class A{ private static A instance = new A(); public static A getInstance() { return instance; } public static void main(String[] args) { A a= A.getInstance(); } } AND public class B{ public B(){}; public static void main(String[] args) { B b= new B(); } } Thanks

    Read the article

  • Multi-threaded Pooled Allocators

    - by Darren Engwirda
    I'm having some issues using pooled memory allocators for std::list objects in a multi-threaded application. The part of the code I'm concerned with runs each thread function in isolation (i.e. there is no communication or synchronization between threads) and therefore I'd like to setup separate memory pools for each thread, where each pool is not thread-safe (and hence fast). I've tried using a shared thread-safe singleton memory pool and found the performance to be poor, as expected. This is a heavily simplified version of the type of thing I'm trying to do. A lot has been included in a pseudo-code kind of way, sorry if it's confusing. /* The thread functor - one instance of MAKE_QUADTREE created for each thread */ class make_quadtree { private: /* A non-thread-safe memory pool for int linked list items, let's say that it's * something along the lines of BOOST::OBJECT_POOL */ pooled_allocator<int> item_pool; /* The problem! - a local class that would be constructed within each std::list as the * allocator but really just delegates to ITEM_POOL */ class local_alloc { public : //!! I understand that I can't access ITEM_POOL from within a nested class like //!! this, that's really my question - can I get something along these lines to //!! work?? pointer allocate (size_t n) { return ( item_pool.allocate(n) ); } }; public : make_quadtree (): item_pool() // only construct 1 instance of ITEM_POOL per // MAKE_QUADTREE object { /* The kind of data structures - vectors of linked lists * The idea is that all of the linked lists should share a local pooled allocator */ std::vector<std::list<int, local_alloc>> lists; /* The actual operations - too complicated to show, but in general: * * - The vector LISTS is grown as a quadtree is built, it's size is the number of * quadtree "boxes" * * - Each element of LISTS (each linked list) represents the ID's of items * contained within each quadtree box (say they're xy points), as the quadtree * is grown a lot of ID pop/push-ing between lists occurs, hence the memory pool * is important for performance */ } }; So really my problem is that I'd like to have one memory pool instance per thread functor instance, but within each thread functor share the pool between multiple std::list objects.

    Read the article

  • Any way to make dialogs appear/disappear with a transition in MFC?

    - by John
    For instance I have a main dialog, when I click a button a smaller dialog appears next to it. But it would be neat if the small one could somehow transition in, rather than simply appear. For instance using transparency, or zooming in, or sliding in from width=0 - full-width. Making an actual dialog do such things isn't too hard, but what about the controls within it? How might we approach this in a way that is reusable on different dialogs?

    Read the article

  • Flex: How do you list private attributes of a class?

    - by mensonge
    Hi, I try to serialize objects with their private attributes, in Flex. The introspection API does not seem to allow it: "The describeType() method returns only public members. The method does not return private members of the caller's superclass or any other class where the caller is not an instance." Is there another way for an instance to know the name of its private members?

    Read the article

  • Concept of creating static Map

    - by chetan
    I want to create a Map object that can lose value only if we explicitly delete it from map. I have created Map object like public static Map<Long,String> listUser =new HasMap<Long,String>(); but every time class object is created new instance of Map is also created that contain null value. I want to create a Map instance that contain value we stored before.

    Read the article

  • php syntax error

    - by Jacksta
    I have 3 files 1) show_createtable.html 2) do_showfielddef.php 3) do_showtble.php 1) First file is for creating a new table for a data base, it is a fom with 2 inputs, Table Name and Number of Fields. THIS WORKS FINE! <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Untitled Document</title> </head> <body> <h1>Step 1: Name and Number</h1> <form method="post" action="do_showfielddef.php" /> <p><strong>Table Name:</strong><br /> <input type="text" name="table_name" size="30" /></p> <p><strong>Number of fields:</strong><br /> <input type="text" name="num_fields" size="30" /></p> <p><input type="submit" name="submit" value="go to step2" /></p> </form> </body> </html> 2) this script validates fields and createa another form to enter all the table rows. This for also WORKS FINE! <?php //validate important input if ((!$_POST[table_name]) || (!$_POST[num_fields])) { header( "location: show_createtable.html"); exit; } //begin creating form for display $form_block = " <form action=\"do_createtable.php\" method=\"post\"> <input name=\"table_name\" type=\"hidden\" value=\"$_POST[table_name]\"> <table cellspacing=\"5\" cellpadding=\"5\"> <tr> <th>Field Name</th><th>Field Type</th><th>Table Length</th> </tr>"; //count from 0 until you reach the number fo fields for ($i = 0; $i <$_POST[num_fields]; $i++) { $form_block .=" <tr> <td align=center><input type=\"texr\" name=\"field name[]\" size=\"30\"></td> <td align=center> <select name=\"field_type[]\"> <option value=\"char\">char</option> <option value=\"date\">date</option> <option value=\"float\">float</option> <option value=\"int\">int</option> <option value=\"text\">text</option> <option value=\"varchar\">varchar</option> </select> </td> <td align=center><input type=\"text\" name=\"field_length[]\" size=\"5\"> </td> </tr>"; } //finish up the form $form_block .= " <tr> <td align=center colspan=3><input type =\"submit\" value=\"create table\"> </td> </tr> </table> </form>"; ?> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Create a database table: Step 2</title> </head> <body> <h1>defnie fields for <? echo "$_POST[table_name]"; ?> </h1> <? echo "$form_block"; ?> </body> </html> Problem is here 3) this form creates the tables and enteres them into the database. I am getting an error on line 37 "Parse error: syntax error, unexpected $end in /home/admin/domains/domaina.com.au/public_html/do_createtable.php on line 37" <? $db_name = "testDB"; $connection = @mysql_connect("localhost", "admin_user", "pass") or die(mysql_error()); $db = @mysql_select_db($db_name, $connection) or die(mysql_error()); $sql = "CREATE TABLE $_POST[table_name]("; for ($i = 0; $i < count($_POST[field_name]); $i++) { $sql .= $_POST[field_name][$i]." ".$_POST[field_type][$i]; if ($_POST[field_length][$i] !="") { $sql .=" (".$_POST[field_length][$i]."),"; } else { $sql .=","; } $sql = substr($sql, 0, -1); $sql .= ")"; $result = mysql_query($sql, $connection) or die(mysql_error()); if ($result) { $msg = "<p>" .$_POST[table_name]." has been created!</p>"; ?> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Create A Database Table: Step 3</title> </head> <body> <h1>Adding table to <? echo "$db_name"; ?>...</h1> <? echo "$msg"; ?> </body> </html>

    Read the article

  • PHP syntax error “unexpected $end”

    - by Jacksta
    I have 3 files 1) show_createtable.html 2) do_showfielddef.php 3) do_showtble.php 1) First file is for creating a new table for a data base, it is a fom with 2 inputs, Table Name and Number of Fields. THIS WORKS FINE! <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Untitled Document</title> </head> <body> <h1>Step 1: Name and Number</h1> <form method="post" action="do_showfielddef.php" /> <p><strong>Table Name:</strong><br /> <input type="text" name="table_name" size="30" /></p> <p><strong>Number of fields:</strong><br /> <input type="text" name="num_fields" size="30" /></p> <p><input type="submit" name="submit" value="go to step2" /></p> </form> </body> </html> 2) this script validates fields and createa another form to enter all the table rows. This for also WORKS FINE! <?php //validate important input if ((!$_POST[table_name]) || (!$_POST[num_fields])) { header( "location: show_createtable.html"); exit; } //begin creating form for display $form_block = " <form action=\"do_createtable.php\" method=\"post\"> <input name=\"table_name\" type=\"hidden\" value=\"$_POST[table_name]\"> <table cellspacing=\"5\" cellpadding=\"5\"> <tr> <th>Field Name</th><th>Field Type</th><th>Table Length</th> </tr>"; //count from 0 until you reach the number fo fields for ($i = 0; $i <$_POST[num_fields]; $i++) { $form_block .=" <tr> <td align=center><input type=\"texr\" name=\"field name[]\" size=\"30\"></td> <td align=center> <select name=\"field_type[]\"> <option value=\"char\">char</option> <option value=\"date\">date</option> <option value=\"float\">float</option> <option value=\"int\">int</option> <option value=\"text\">text</option> <option value=\"varchar\">varchar</option> </select> </td> <td align=center><input type=\"text\" name=\"field_length[]\" size=\"5\"> </td> </tr>"; } //finish up the form $form_block .= " <tr> <td align=center colspan=3><input type =\"submit\" value=\"create table\"> </td> </tr> </table> </form>"; ?> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Create a database table: Step 2</title> </head> <body> <h1>defnie fields for <? echo "$_POST[table_name]"; ?> </h1> <? echo "$form_block"; ?> </body> </html> Problem is here 3) this form creates the tables and enteres them into the database. I am getting an error on line 37 "Parse error: syntax error, unexpected $end in /home/admin/domains/domaina.com.au/public_html/do_createtable.php on line 37" <? $db_name = "testDB"; $connection = @mysql_connect("localhost", "admin_user", "pass") or die(mysql_error()); $db = @mysql_select_db($db_name, $connection) or die(mysql_error()); $sql = "CREATE TABLE $_POST[table_name]("; for ($i = 0; $i < count($_POST[field_name]); $i++) { $sql .= $_POST[field_name][$i]." ".$_POST[field_type][$i]; if ($_POST[field_length][$i] !="") { $sql .=" (".$_POST[field_length][$i]."),"; } else { $sql .=","; } $sql = substr($sql, 0, -1); $sql .= ")"; $result = mysql_query($sql, $connection) or die(mysql_error()); if ($result) { $msg = "<p>" .$_POST[table_name]." has been created!</p>"; ?> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Create A Database Table: Step 3</title> </head> <body> <h1>Adding table to <? echo "$db_name"; ?>...</h1> <? echo "$msg"; ?> </body> </html>

    Read the article

  • substrings and multiple textfields, AS3

    - by VideoDnd
    How do I get my text fields to populate correctly and show single digits? Description Each textfield receives a substring. This doesn't limit it's input, because the text fields shows extra numbers. The counters are set to 2,200,000.00, just to see if the numbers are populating. Ex A is the one I'm trying to fix. Ex A the one I want to fix //Tweening method 'could substitute code with Tweener' import fl.transitions.Tween; import fl.transitions.easing.*; //Timer that will run a sec and repeat var timer:Timer = new Timer(1000); //Integer values var count:int = +220000000; var fcount:int = 0; //Events and starting timer timer.addEventListener(TimerEvent.TIMER, incrementCounter); addEventListener(Event.ENTER_FRAME, checkOdometerPosition); timer.start(); //Tween Variables var smoothLoop:int = 0; var originalYPosition:Number = 0; var upwardYPosition:Number = -99; //Formatting String function formatCount(i:int):String { var fraction:int = i % 100; var whole:int = i / 100; return ("0000000" + whole).substr(-7, 7) + "." + (fraction < 10 ? "0" + fraction : fraction); } //First Digit function checkOdometerPosition(event:Event):void{ if (seconds9.y <= upwardYPosition){ var toText:String = formatCount(fcount); //seconds9.firstDigit.text = formatCount(fcount); seconds9.firstDigit.text = toText.substr(9, 9); seconds9.y = originalYPosition; seconds8.firstDigit.text = toText.substr(8, 8); seconds8.y = originalYPosition; seconds7dec.firstDigit.text = toText.substr(7, 7); seconds7dec.y = originalYPosition; seconds6.firstDigit.text = toText.substr(6, 6); seconds6.y = originalYPosition; seconds5.firstDigit.text = toText.substr(5, 5); seconds5.y = originalYPosition; seconds5.firstDigit.text = toText.substr(4, 4); seconds5.y = originalYPosition; seconds3.firstDigit.text = toText.substr(3, 3); seconds3.y = originalYPosition; seconds2.firstDigit.text = toText.substr(2, 2); seconds2.y = originalYPosition; seconds1.firstDigit.text = toText.substr(1, 1); seconds1.y = originalYPosition; seconds1.firstDigit.text = toText.substr(1, 1); seconds1.y = originalYPosition; seconds0.firstDigit.text = toText.substr(0, 1); seconds0.y = originalYPosition; } } //Second Digit function incrementCounter(event:TimerEvent):void{ count++; fcount=int(count) if (smoothLoop < 9){ smoothLoop++; } else { smoothLoop = 0; } var lolly:String = formatCount(fcount-1); //seconds9.secondDigit.text = formatCount(fcount); seconds9.secondDigit.text = lolly.substr(9, 9); var addTween9:Tween = new Tween(seconds9, "y", Strong.easeOut,0,-222, .7, true); seconds8.secondDigit.text = lolly.substr(8, 8); var addTween8:Tween = new Tween(seconds8, "y", Strong.easeOut,0,-222, .7, true); seconds7dec.secondDigit.text = lolly.substr(7, 7); var addTween7dec:Tween = new Tween(seconds7dec, "y", Strong.easeOut,0,-222, .7, true); seconds6.secondDigit.text = lolly.substr(6, 6); var addTween6:Tween = new Tween(seconds6, "y", Strong.easeOut,0,-222, .7, true); seconds5.secondDigit.text = lolly.substr(5, 5); var addTween5:Tween = new Tween(seconds5, "y", Strong.easeOut,0,-222, .7, true); seconds4.secondDigit.text = lolly.substr(4, 4); var addTween4:Tween = new Tween(seconds4, "y", Strong.easeOut,0,-222, .7, true); seconds3.secondDigit.text = lolly.substr(3, 3); var addTween3:Tween = new Tween(seconds3, "y", Strong.easeOut,0,-222, .7, true); seconds2.secondDigit.text = lolly.substr(2, 2); var addTween2:Tween = new Tween(seconds2, "y", Strong.easeOut,0,-222, .7, true); seconds1.secondDigit.text = lolly.substr(1, 1); var addTween1:Tween = new Tween(seconds1, "y", Strong.easeOut,0,-222, .7, true); seconds0.secondDigit.text = lolly.substr(0, 1); var addTween0:Tween = new Tween(seconds0, "y", Strong.easeOut,0,-222, .7, true); } Ex A has 10 text objects, each with a pair of text fields. It’s move complex than Ex B, because it has a Y animation and pairs of numbers. The text objects are animated to create a scrolling effect. It moves vertically, and has a lead number and a catch up number contained in each symbol. See illustration for more description. Ex B work fine! for example only //STRING SPLITTER COUNTER with nine individual text fields //Timer settings var delay:uint = 1000/100; var repeat:uint = 0; var timer:Timer; timer = new Timer(delay,repeat); timer.addEventListener(TimerEvent.TIMER, incrementCounter); timer.start(); //Integer values var count:int = 0; var fcount:int = 0; //Format Count function formatCount(i:int):String { var fraction:int = i % 100; var whole:int = i / 100; return ("0000000" + whole).substr(-7, 7) + "." + (fraction < 10 ? "0" + fraction : fraction); } //Split strings off to individual text fields function incrementCounter(event:TimerEvent) { count++; fcount=int(count+220000000) var toText:String = formatCount(fcount); mytext9.text = toText.substr(9, 9); mytext8.text = toText.substr(8, 8); mytext7dec.text = toText.substr(7, 7); mytext6.text = toText.substr(6, 6); mytext5.text = toText.substr(5, 5); mytext4.text = toText.substr(4, 4); mytext3.text = toText.substr(3, 3); mytext2.text = toText.substr(2, 2); mytext1.text = toText.substr(1, 1); mytext0.text = toText.substr(0, 1); }

    Read the article

  • What's the best way to call an IBAction from within code?

    - by Rob
    Say for instance I have an IBAction that is hooked up to a button in interface builder. - (IBAction)functionToBeCalled:(id)sender { // do something here } Within my code, say for instance in another method, what is the best way to call that IBAction? If I try to call it like this, I receive an error: [self functionToBeCalled:]; But, if I try to call it like this (cheating a bit, I think), it works fine: [self functionToBeCalled:0]; What is the proper way to call it though?

    Read the article

  • Haskell type classes and type families (cont'd)

    - by Giuseppe Maggiore
    I need some help in figuring a compiler error which is really driving me nuts... I have the following type class: infixl 7 --> class Selectable a s b where type Res a s b :: * (-->) :: (CNum n) => (Reference s a) -> (n,(a->b),(a->b->a)) -> Res a s b which I instance twice. First time goes like a charm: instance Selectable a s b where type Res a s b = Reference s b (-->) (Reference get set) (_,read,write) = (Reference (\s -> let (v,s') = get s in (read v,s')) (\s -> \x -> let (v,s') = get s v' = write v x (_,s'') = set s' v' in (x,s''))) since the type checker infers (-->) :: Reference s a -> (n,a->b,a->b->a) -> Reference s b and this signature matches with the class signature for (--) since Res a s b = Reference s b Now I add a second instance and everything breaks: instance (Recursive a, Rec a ~ reca) => Selectable a s (Method reca b c) where type Res a s (Method reca b c) = b -> Reference s c (-->) (Reference get set) (_,read,write) = \(x :: b) -> from_constant( Constant(\(s :: s)-> let (v,s') = get s :: (a,s) m = read v ry = m x :: Reference (reca) c (y,v') = getter ry (cons v) :: (c,reca) v'' = elim v' (_,s'') = set s' v'' in (y,s''))) :: Reference s c the compiler complains that Couldn't match expected type `Res a s (Method reca b c)' against inferred type `b -> Reference s c' The lambda expression `\ (x :: b) -> ...' has one argument, which does not match its type In the expression: \ (x :: b) -> from_constant (Constant (\ (s :: s) -> let ... in ...)) :: Reference s c In the definition of `-->': --> (Reference get set) (_, read, write) = \ (x :: b) -> from_constant (Constant (\ (s :: s) -> ...)) :: Reference s c reading carefully the compiler is telling me that it has inferred the type of (--) thusly: (-->) :: Reference s a -> (n,a->(Method reca b c),a->(Method reca b c)->a) -> (b -> Reference s c) which is correct since Res a s (Method reca b c) = b -> Reference s c but why can't it match the two definitions? Sorry for not offering a more succint and standalone example, but in this case I cannot figure how to do it...

    Read the article

  • How to copy or clone model?

    - by Zeck
    I have a model Book with attributes id, name, price. I have an instance of Book: b1 = Book.new b1.name = "Blah" b1.price = 12.5 b1.save I would like to copy b1, create another instance of the Product model. I'm tryid p1=b1.clone then p1.save but it didn't work. Any idea? And my environment is: Netbeans 6.9 RC2 JRuby 1.5.0 Thanks

    Read the article

  • Is it easy to do IPC with wxWidgets?

    - by George Edison
    Is it easy to create an IPC setup with wxWidgets? I have an application that needs to detect if a previous instance is running and send a message to the running instance with a string value. Is there an easier way to do this than setting up a wxServer and wxClient-derived class?

    Read the article

  • GWT - Reusing Callback Class

    - by moorsu
    My custom callback class implements AsyncCallback (like MyAsyncCallback implements AsyncCallback) and planning use single instance of MyAsyncCallback for multiple rpc method executions. Is this approach safe?. Or should have to create new instance of MyAsyncCallback for every interaction from browser to server?. I am kind of tired of seeing so many anonymous AsyncCallback code blocks. Thanks for your input

    Read the article

  • The internal implementation of R's dataset

    - by Yin Zhu
    I am trying to build a data processing program. Currently I use a double matrix to represent the data table, each row is an instance, each column represents a feature. I also have an extra vector as the target value for each instance, it is of double type for regression, it is of integer for classification. I want to make it more general. I am wondering how what kind of structure R uses to store a dataset, i.e. the internal implementation in R.

    Read the article

  • post object to wcf rest service

    - by gleasonomicon
    I'm using the WCF Rest service application project template in visual studio. I'm just learning about REST, and I was wondering how I would post a SampleItem object to the following method: [WebInvoke(UriTemplate = "", Method = "POST")] public SampleItem Create(SampleItem instance) { // TODO: Add the new instance of SampleItem to the collection throw new NotImplementedException(); } I get the general concepts of gets for the purposes of grabbing data, but I'm not sure how I would post the object in code (or just through a browser for testing) to the service.

    Read the article

  • Limiting JMS Destination Instances

    - by jumponadoughnut
    Is it possible to limit the number of JMS receiver instances to a single instance? I.e. only process a single message from a queue at any one time? The reason I ask is because I have a fairly intensive render type process to run for each message (potentially many thousands). I'd like to limit the execution of this code to a single instance at a time. My application server is JBoss AS 6.0 Any help much appreciated

    Read the article

  • Sinatra/Rails: Persisting custom class instances during app lifetime

    - by knoopx
    Can I assert rails/sinatra apps are initialized only once and all requests share the same app instance? or do new requests spawn new app instances? Is it possible to instance custom classes and persist them during app lifetime without using sessions, database storages or third party services? If so, what are the implications from a thread-safeness point of view? I'm trying to figure how to implement a web-based download manager and I'm currently evaluating ruby-based frameworks.

    Read the article

  • Scala: getting the name of the class the trait is mixed in

    - by Alexey Romanov
    Given an instance of a class, we can obviously return its name: trait MixedInClassDiscovery { val className = this.getClass.getName } class AClass extends MixedInClassDiscovery { ... this.className // returns "AClass" ... } But this way uses reflection, once for every instance of AClass. Can the same be done once for every class, instead? One solution which comes to mind is to mix it into companion objects instead of classes themselves.

    Read the article

  • Sharing DefaultHttpClient in Android. To synchronize or not to synchronize?

    - by johnrock
    In an Android app, I am using one static instance of org.apache.http.impl.client.DefaultHttpClient and sharing that instance in all activities and services of the app, so that this client may be used to log in once to a remote server and all subsequent user requests to that remote server will remain authenticated. Every activity or Service that makes a GET or POST to this remote server calls the same method : MyUtilityClass.gettHttpClient() Do I need to worry about synchronization of this httpclient? If so, what is the best way to handle this?

    Read the article

< Previous Page | 166 167 168 169 170 171 172 173 174 175 176 177  | Next Page >