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• Multithreading: Read from / write to a pipe

  - by Tero Jokinen

  I write some data to a pipe - possibly lots of data and at random intervals. How to read the data from the pipe? Is this ok: in the main thread (current process) create two more threads (2, 3) the second thread writes sometimes to the pipe (and flush-es the pipe?) the 3rd thread has infinite loop which reads the pipe (and then sleeps for some time) Is this so far correct? Now, there are a few thing I don't understand: do I have to lock (mutex?) the pipe on write? IIRC, when writing to pipe and its buffer gets full, the write end will block until I read the already written data, right? How to check for read data in the pipe, not too often, not too rarely? So that the second thread wont block? Is there something like select for pipes? It is possible to set the pipe to unbuffered more or I have to flush it regularly - which one is better? Should I create one more thread, just for flushing the pipe after write? Because flush blocks as well, when the buffer is full, right? I just don't want the 1st and 2nd thread to block.... [Edit] Sorry, I thought the question is platform agnostic but just in case: I'm looking at this from Win32 perspective, possibly MinGW C...

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• How do I access a <form> that is not the master page <form>?

  - by VBCSharp

  Winforms developer converting to web developer. I know the part about the Master Page having the tag, what is not clear is if I can or can not have another in one of my content pages. I have been seeing both answers doing searches. I see yes you can if only one has runat=server. The thing is I have a that contains several radio buttons on a web page that has a master page. I have a .js file that has a function if I send the name into it, it will loop thru the controls in the form to see which one is selected and return the desired date horizon(MTD, QTD, YTD, etc.). When I run this on a non master page web page it works fine. However, when I run on a web page that has a master page I can't seem to get to the element. I tried getElementByID, I tried looping through the page elements, etc. Maybe I am going about this incorrectly and I hope someone can straighten me out. Here is the code from my .js file that may help explain what I am trying to do a little better. var frmDateRanges = document.getElementById(formFieldName); var chosen; var len = frmDateRanges.DateRanges.length; for(i=0;i<len;i++) { if(frmDateRanges.DateRanges[i].checked) { chosen = frmDateRanges.DateRanges[i].value; } } where formFieldName is an arguement that is passed into the function and DateRanges is the name value given to the radio buttons. In the button I call this function I have: onclick ="FunctionCall('frmDateRanges')" FunctionCall is just for description purposes, 'frmDateRanges' is the name and id given to the form action="" Thanks for the help as I am stumped at this point. If there is a better way to do this please let me know that as well.

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• UITableViewCell: how to verify the kind of accessoryType in all cells?

  - by R31n4ld0_

  Hello, Guys. I have a UITableView in that some cells are marked with UITableViewCellAccessoryCheckmark at the initialization of the view. When the user selects another row, I have to check if the maximum number of selected rows was achieved before. To do that, I used the code bellow: - (NSInteger)tableView:(UITableView *)tableView numberOfSelectedRowsInSection:(NSInteger)section{ NSInteger numberOfRows = [self tableView:tableView numberOfRowsInSection:section]; NSInteger numberOfSelectedRows = 0; for (int i = 0; i < numberOfRows; i++) { UITableViewCell *otherCell = [tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:i inSection:section]]; if (otherCell.accessoryType == UITableViewCellAccessoryCheckmark) { numberOfSelectedRows++; } } return numberOfSelectedRows; } If my number of rows is, as example, 20, the variable numberOfRows is setted correctly with 20. Lets say that 13 rows already are marked with UITableViewCellAccessoryCheckmark. So, numberOfSelectedRows should be 13 after the loop, but only the marked and VISIBLE cells are considered. So, if I have 9 cells showed and 7 are marked, the numberOfSelectedRows returns 7 instead of 13 (but the for iterate 20 times, as expected). Is this a correct behavior of UITableView or it is a bug of iPhone simulator? Thanks in advance.

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• CSV Parser works in windows, not linux.

  - by ladookie

  I'm parsing a CSV file that looks like this: E1,E2,E7,E8,,, E2,E1,E3,,,, E3,E2,E8,,, E4,E5,E8,E11,,, I store the first entry in each line in a string, and the rest go in a vector of strings: while (getline(file_input, line)) { stringstream tokenizer; tokenizer << line; getline(tokenizer, roomID, ','); vector<string> aVector; while (getline(tokenizer, adjRoomID, ',')) { if (!adjRoomID.empty()) { aVector.push_back(adjRoomID); } } Room aRoom(roomID, aVector); rooms.addToTail(aRoom); } In windows this works fine, however in Linux the first entry of each vector mysteriously loses the first character. For Example in the first iteration through the while loop: roomID would be E1 and aVector would be 2 E7 E8 then the second iteration: roomID would be E2 and aVector would be 1 E3 Notice the missing E's in the first entry of aVector. when I put in some debugging code it appears that it is initially being stored correctly in the vector, but then something overwrites it. Kudos to whoever figures this one out. Seems bizarre to me. rooms is declared as such: DLList<Room> rooms where DLList stands for Doubly-Linked list.

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• Is safe ( documented behaviour? ) to delete the domain of an iterator in execution

  - by PoorLuzer

  I wanted to know if is safe ( documented behaviour? ) to delete the domain space of an iterator in execution in Python. Consider the code: import os import sys sampleSpace = [ x*x for x in range( 7 ) ] print sampleSpace for dx in sampleSpace: print str( dx ) if dx == 1: del sampleSpace[ 1 ] del sampleSpace[ 3 ] elif dx == 25: del sampleSpace[ -1 ] print sampleSpace 'sampleSpace' is what I call 'the domain space of an iterator' ( if there is a more appropriate word/phrase, lemme know ). What I am doing is deleting values from it while the iterator 'dx' is running through it. Here is what I expect from the code : Iteration versus element being pointed to (*): 0: [*0, 1, 4, 9, 16, 25, 36] 1: [0, *1, 4, 9, 16, 25, 36] ( delete 2nd and 5th element after this iteration ) 2: [0, 4, *9, 25, 36] 3: [0, 4, 9, *25, 36] ( delete -1th element after this iteration ) 4: [0, 4, 9, 25*] ( as the iterator points to nothing/end of list, the loop terminates ) .. and here is what I get: [0, 1, 4, 9, 16, 25, 36] 0 1 9 25 [0, 4, 9, 25] As you can see - what I expect is what I get - which is contrary to the behaviour I have had from other languages in such a scenario. Hence - I wanted to ask you if there is some rule like "the iterator becomes invalid if you mutate its space during iteration" in Python? Is it safe ( documented behaviour? ) in Python to do stuff like this?

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• How to get a category listing from Magento?

  - by alex

  I want to create a page in Magento that shows a visual representation of the categories.. example CATEGORY product 1 product 2 ANOTHER CATEGORY product 3 My problem is, their database is organised very differently to what I've seen in the past. They have tables dedicated to data types like varchar, int, etc. I assume this is for performance or similiar. I haven't found a way to use MySQL to query the database and get a list of categories. I'd then like to match these categories to products, to get a listing of products for each category. Unfortunately Magento seems to make this very difficult. Also I have not found a method that will work from within a page block.. I have created showcase.phtml and put it in the XML layout and it displays and runs it's PHP code. I was hoping for something easy like looping through $this-getAllCategories(); and then a nested loop inside with something like $category-getChildProducts(); Can anyone help me? Thank you!

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• Error In VB.Net code

  - by Michael

  I am getting the error "Format Exception was unhandled at "Do While objectReader.Peek < -1 " and after. any help would be wonderful. 'Date: Class 03/20/2010 'Program Purpose: When code is executed data will be pulled from a text file 'that contains the named storms to find the average number of storms during the time 'period chosen by the user and to find the most active year. between the range of 'years 1990 and 2008 Option Strict On Public Class frmHurricane Private _intNumberOfHuricanes As Integer = 5 Public Shared _intSizeOfArray As Integer = 7 Public Shared _strHuricaneList(_intSizeOfArray) As String Private _strID(_intSizeOfArray) As String Private _decYears(_intSizeOfArray) As Decimal Private _decFinal(_intSizeOfArray) As Decimal Private _intNumber(_intSizeOfArray) As Integer Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load 'The frmHurricane load event reads the Hurricane text file and 'fill the combotBox object with the data. 'Initialize an instance of the StreamReader Object and declare variable page 675 on the book Dim objectReader As IO.StreamReader Dim strLocationAndNameOfFile As String = "C:\huricanes.txt" Dim intCount As Integer = 0 Dim intFill As Integer Dim strFileError As String = "The file is not available. Please restart application when available" 'This is where we code the file if it exist. If IO.File.Exists(strLocationAndNameOfFile) Then objectReader = IO.File.OpenText(strLocationAndNameOfFile) 'Read the file line by line until the file is complete Do While objectReader.Peek <> -1 **_strHuricaneList(intCount) = objectReader.ReadLine() _strID(intCount) = objectReader.ReadLine() _decYears(intCount) = Convert.ToDecimal(objectReader.ReadLine()) _intNumber(intCount) = Convert.ToInt32(objectReader.ReadLine()) intCount += 1** Loop objectReader.Close() 'With any luck the data will go to the Data Box For intFill = 0 To (_strID.Length - 1) Me.cboByYear.Items.Add(_strID(intFill)) Next Else MsgBox(strFileError, , "Error") Me.Close() End If End Sub

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• IDENTITY_INSERT ON inside of cursor does not allow inserted id

  - by Mac

  I am trying to set some id's for a bunch of rows in a database where the id column is an identity. I've created a cursor to loop through the rows and update the ids with incrementing negative numbers (-1,-2,-3 etc). When I updated just one row turning on the IDENTITY_INSERT it worked fine but as soon as I try and use it in a cursor, it throws the following error. Msg 8102, Level 16, State 1, Line 22 Cannot update identity column 'myRowID'. DECLARE @MinId INT; SET @MinId = (SELECT MIN(myRowId) FROM myTable)-1; DECLARE myCursor CURSOR FOR SELECT myRowId FROM dbo.myTable WHERE myRowId > 17095 OPEN myCursor DECLARE @myRowId INT FETCH NEXT FROM myCursor INTO @myRowId WHILE (@@FETCH_STATUS <> -1) BEGIN SET IDENTITY_INSERT dbo.myTable ON; --UPDATE dbo.myTable --SET myRowId = @MinId --WHERE myRowId = @myRowId; PRINT (N'ID: ' + CAST(@myRowId AS VARCHAR(10)) + N' NewID: ' + CAST(@MinId AS VARCHAR(4))); SET @MinId = @MinId - 1; FETCH NEXT FROM myCursor INTO @myRowId END CLOSE myCursor DEALLOCATE myCursor GO SET IDENTITY_INSERT dbo.myTable OFF; GO Does anyone know what I'm doing wrong?

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• Java - Thread - Problem in one of the Sun's tutorial

  - by Yatendra Goel

  I was reading this Sun's tutorial on Thread. I found a block of code there which I think can be replaced by a code of fewer lines. I wonder why Sun's expert programmers followed that long way when the task can be accomplished with a code of fewer lines. I am asking this question so as to know that if I am missing something that the tutorial wants to convey. The block of code is as follows: t.start(); threadMessage("Waiting for MessageLoop thread to finish"); //loop until MessageLoop thread exits while (t.isAlive()) { threadMessage("Still waiting..."); //Wait maximum of 1 second for MessageLoop thread to //finish. t.join(1000); if (((System.currentTimeMillis() - startTime) > patience) && t.isAlive()) { threadMessage("Tired of waiting!"); t.interrupt(); //Shouldn't be long now -- wait indefinitely t.join(); } } threadMessage("Finally!"); I think that the above code can be replaced by the following: t.start(); t.join(patience); // InterruptedException is thrown by the main method so no need to handle it if(t.isAlive()) { // t's thread couldn't finish in the patience time threadMessage("Tired of waiting!"); t.interrupt(); t.join(); } threadMessage("Finally!");

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• Disable home button in android toddler app?

  - by cmerrell

  I've developed and app that is a slide show of pictures which each play a sound when you tap them. It's like a picture book for ages 2-4. The problem is, since android won't let you capture a home button press and essentially disable it, when parents give the phone to their child to play with unattended (brave parent), the child can inadvertenly exit the app and then make calls or otherwise tweak the phone. There are two other apps that currently have a psuedo fix for this issue. The apps are Toddler Lock and ToddlePhone. I've tried contacting the developers of these apps for some guidance but they haven't been willing to disclose anything, which if fine, but does anyone here have any suggestions? It looks like both of those other apps are acting like a home screen replacement app. When you enable the "childproof mode" on those apps the user is prompted to chose and app for the action and the choices are "Launcher, LauncherPro, etc." plus the toddler app. You then have to make the toddler app the default and voila, the phone is "locked" and can only be "unlocked" using a key combination or touching the four corners of the screen, etc. when you "unlock" the phone. your normal home screen app default restored. You don't even have to make the toddler app the default the next time you enable the "childproof mode". I have read that these two apps have problems with Samsung phones and they can cause an an infinite crash-and-restart-loop that requires a factory reset to fix. Obviously this is not the ideal solution to the problem but it looks like the only one availiable at this point. Does anyone have any ideas on how to implement a "childproof mode"?

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• Jquery data() returning undefined

  - by David Lockwood

  I have been doing a simple jquery data() test. However it is returning undefined. It works on jsfiddle though (http://jsfiddle.net/yrCdj/). I have a jinja2 loop which populates a div and I want to tag it with some metadata for use later : {% for s in siteInfo[:markers[0]] %} <div class="sitebox2"> <script> $(".sitebox2:last").append('<a href="/sites/d?siteid={{s[5]}}">{{s[0]}}</a><br>Distance from {{loc}} is {{s[6]}} km.<br>'); $(".sitebox2:last").data('fruit', 'apple'); </script> </div> {% endfor %} I then try to call this data to test if it is working: <script type="text/javascript"> $(".sitebox2").each(function(k, v) { var f = $(v).data('fruit'); alert(f); }); </script> It returns undefined. Any ideas on what is going wrong?

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• Strange Puzzle - Invalid memory access of location

  - by Rob Graeber

  The error message I'm getting consistently is: Invalid memory access of location 0x8 rip=0x10cf4ab28 What I'm doing is making a basic stock backtesting system, that is iterating huge arrays of stocks/historical data across various algorithms, using java + eclipse on the latest Mac Os X. I tracked down the code that seems to be causing it. A method that is used to get the massive arrays of data and is called thousands of times. Nothing is retained so I don't think there is a memory leak. However there seems to be a set limit of around 7000 times I can iterate over it before I get the memory error. The weird thing is that it works perfectly in debug mode. Does anyone know what debug mode does differently in Eclipse? Giving the jvm more memory doesn't help, and it appears to work fine using -xint. And again it works perfectly in debug mode. public static List<Stock> getStockArray(ExchangeType e){ List<Stock> stockArray = new ArrayList<Stock>(); if(e == ExchangeType.ALL){ stockArray.addAll(getStockArray(ExchangeType.NYSE)); stockArray.addAll(getStockArray(ExchangeType.NASDAQ)); }else if(e == ExchangeType.ETF){ stockArray.addAll(etfStockArray); }else if(e == ExchangeType.NYSE){ stockArray.addAll(nyseStockArray); }else if(e == ExchangeType.NASDAQ){ stockArray.addAll(nasdaqStockArray); } return stockArray; } A simple loop like this, iterated over 1000s of times, will cause the memory error. But not in debug mode. for (Stock stock : StockDatabase.getStockArray(ExchangeType.ETF)) { System.out.println(stock.symbol); }

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• Blit SDL_Surface onto another SDL_Surface and apply a colorkey

  - by NordCoder

  I want to load an SDL_Surface into an OpenGL texture with padding (so that NPOT-POT) and apply a color key on the surface afterwards. I either end up colorkeying all pixels, regardless of their color, or not colorkey anything at all. I have tried a lot of different things, but none of them seem to work. Here's the working snippet of my code. I use a custom color class for the colorkey (range [0-1]): // Create an empty surface with the same settings as the original image SDL_Surface* paddedImage = SDL_CreateRGBSurface(image->flags, width, height, image->format->BitsPerPixel, #if SDL_BYTEORDER == SDL_BIG_ENDIAN 0xff000000, 0x00ff0000, 0x0000ff00, 0x000000ff #else 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000 #endif ); // Map RGBA color to pixel format value Uint32 colorKeyPixelFormat = SDL_MapRGBA(paddedImage->format, static_cast<Uint8>(colorKey.R * 255), static_cast<Uint8>(colorKey.G * 255), static_cast<Uint8>(colorKey.B * 255), static_cast<Uint8>(colorKey.A * 255)); SDL_FillRect(paddedImage, NULL, colorKeyPixelFormat); // Blit the image onto the padded image SDL_BlitSurface(image, NULL, paddedImage, NULL); SDL_SetColorKey(paddedImage, SDL_SRCCOLORKEY, colorKeyPixelFormat); Afterwards, I generate an OpenGL texture from paddedImage using similar code to the SDL+OpenGL texture loading code found online (I'll post if necessary). This code works if I just want the texture with or without padding, and is likely not the problem. I realize that I set all pixels in paddedImage to have alpha zero which causes the first problem I mentioned, but I can't seem to figure out how to do this. Should I just loop over the pixels and set the appropriate colors to have alpha zero?

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• Using LINQ, need help splitting a byte array on data received from Silverlight sockets

  - by gcadmes

  The message packats received contains multiple messages deliniated by a header=0xFD and a footer=0xFE // sample message packet with three // different size messages List<byte> receiveBuffer = new List<byte>(); receiveBuffer.AddRange(new byte[] { 0xFD, 1, 2, 0xFE, 0xFD, 1, 2, 3, 4, 5, 6, 7, 8, 0xFE, 0xFD, 33, 65, 25, 44, 0xFE}); // note: this sample code is without synchronization, // statements, error handling...etc. while (receiveBuffer.Count > 0) { var bytesInRange = receiveBuffer.TakeWhile(n => n != 0xFE); foreach (var n in bytesInRange) Console.WriteLine(n); // process message.. // 1) remove bytes read from receive buffer // 2) construct message object... // 3) etc... receiveBuffer.RemoveRange(0, bytesInRange.Count()); } As you can see, (including header/footer) the first message in this message packet contains 4 bytes, and the 2nd message contains 10 bytes,a and the 3rd message contains 6 bytes. In the while loop, I was expecting the TakeWhile to add the bytes that did not equal the footer part of the message. Note: Since I am removing the bytes after reading them, the header can always be expected to be at position '0'. I searched examples for splitting byte arrays, but non demonstrated splitting on arrays of unknown and fluctuating sizes. Any help will be greatly appreciated. thanks much!

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• Jquery push data to the good row.

  - by marharépa

  Hi! This is my big problem. This script put the information to a table. function handleAccountFeed(result) { var entries = result.feed.getEntries(); var outputTable = ['<table><tr>', '<th>Account Name</th>', '<th>Profile Name</th>', '<th>Profile ID</th>', '<th>Table Id</th></tr>']; for (var i = 0, entry; entry = entries[i]; ++i) { var row = [ entry.getPropertyValue('ga:AccountName'), entry.getTitle().getText(), entry.getPropertyValue('ga:ProfileId'), entry.getTableId().getValue() ].join('</td><td>'); outputTable.push('<tr><td>', row, '</td></tr>'); } outputTable.push('</table>'); document.getElementById('outputDiv').innerHTML = outputTable.join(''); } I've got an own SMARTY template, which makes a table: <table id="stuffs"> <tbody> {section name=i loop=$ownsites} <tr><td>{$ownsites[i].id}</td><td>{$ownsites[i].domain}</td><td>PLACE</td></tr> {/section} <tbody> </table> I'd like to put the TableId (getTableId().getValue()) to that row's PLACE where {$ownsites[i].domain} is equal to the jquery row's Title (getTitle().getText()) How can i do this within this jQuery script?

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• loading.gif ( but customized )

  - by 422

  I know the various websites around the tinternet, that allow you to customize a loading.gif etc, but what I wanted to know... Is there a way, aside from creating a gif with adobe etc, to create custom text loading... So instead of the ubiquitous spinner, you can specify text that animates whilst an image loads. I have searched high and low, and not found anything. Nearest I got was a jquery spinner, but thats not what I am after. Wondered if any of you guys had come across this before. If so, what did you do to customize it.. Example: Sometimes you may see the following animated ( as a gif ) L...... LO..... LOA.... LOAD... LOADI.. LOADIN. LOADING I know the above is done by creating a loop of animations, but wondered if there was a more upto date method of creating custom loading messages, perhaps using jquery ... I have seen it done in flash etc

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• Stream buffering issue

  - by Kolyunya

  The mod_rewrite documentation states that it is a strict requirement to disable in(out)put buffering in a rewrite program. Keeping that in mind I've written a simple program (I do know that it lacks the EOF check but this is not an issue and it saves one condition check per loop): #include <stdio.h> #include <stdlib.h> int main ( void ) { setvbuf(stdin,NULL,_IOLBF,4200); setvbuf(stdout,NULL,_IOLBF,4200); int character; while ( 42 ) { character = getchar(); if ( character == '-' ) { character = '_'; } putchar(character); } return 42 - 42; } After making some measurements I was shocked - it was over 9,000 times slower than the demo Perl script provided by the documentation: #!/usr/bin/perl $| = 1; # Turn off I/O buffering while (<STDIN>) { s/-/_/g; # Replace dashes with underscores print $_; } Now I have two related questions: Question 1. I believe that the streams may be line buffered since Apache sends a new line after each path. Am I correct? Switching my program to setvbuf(stdin,NULL,_IOLBF,4200); setvbuf(stdout,NULL,_IOLBF,4200); makes it twice as fast as Perl one. This should not hit Apache's performance, should it? Question 2. How can one write a program in C which will use unbuffered streams (like Perl one) and will perform as fast as Perl one?

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• Shell Scripting: Generating output file name in script and then writing to it

  - by NewShellScripter

  Hello, I have a shell script where a user passes different sizes as command line arguments. For each of those sizes, I want to perform some task, then save the output of that task into a .txt file with the size in the name. How can I take the command line passed and make that part of a stringname for the output file? I save the output file in a directory specified by another command line argument. Perhaps an example will clear it up. In the foor lop, the i value represents the command line argument I need to use, but $$i doesnt work. ./runMe arg1 arg2 outputDir [size1 size2 size3...] for ((i=4; i<$#; i++ )) do ping -s $$i google.com >> $outputDir/$$iresults.txt done I need to know how to build the $outputDir/$$iresults.txt string. Also, the ping -s $$i doesnt work. Its like I need two levels of replacement. I need to replace the $[$i] inner $i with the value in the loop, like 4 for ex, making it $4. Then replace $4 with the 4th command line argument! Any help would be greatly appreciated. Thanks!

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• Multilangual website using ASP and a database

  - by Noam Smadja

  i want to consult about something i do. my website has 3 languages. Hebrew (main), english and russian. i am using a database having a table with the fields: ID, fieldName, 1, 2, 3. where 1 2 3 are the languages. upon entering the website language 1 (hebrew) is chosen automaticly until you choose another. and saved as a session("currentLanguage"). i wrote a function langstirng whice recieves a field name and prints the value acording to the language in session("currentLanguage"): Dim languageStrings Set languageStrings = Server.CreateObject("ADODB.Recordset") languageStrings.ActiveConnection = MM_KerenDB_STRING languageStrings.Source = "SELECT fieldName,"&current_Language&"FROM Multilangual" languageStrings.CursorType = 0 languageStrings.CursorLocation = 2 languageStrings.LockType = 1 languageStrings.Open() sub langstring(fieldName) do while NOT(languageStrings.EOF) if (languageStrings.fields.item("fieldName").value = fieldName) then exit do else languageStrings.movenext end if loop if (languageStrings.EOF) then response.Write("***"&fieldName&"***") else response.Write(languageStrings.fields.item(currentLanguage+1).value) end if languageStrings.movefirst end sub and i use it like so: <div>langstring("header")</div>. i find it stupid that i keep sending the query to the server on any and every page. since the multilangual table does not change "THAT" often i want to somehow save the recordset for the current browsing. I am looking help for THIS solution, Please.

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• I want a function to return a type of the subclass its invoked from

  - by Jay

  I want to have a function defined in a superclass that returns a value of the type of the subclass that is used to invoke the function. That is, say I have class A with a function plugh. Then I create subclasses B and C that extend A. I want B.plugh to return a B and C.plugh to return a C. Yes, they could return an A, but then the caller would have to either cast it to the right subtype, which is a pain when used a lot, or declare the receiving variable to be of the supertype, which loses type safety. So I was trying to do this with generics, writing something like this: class A<T extends A> { private T foo; public T getFoo() { return foo; } } class B extends A<B> { public void calcFoo() { foo=... whatever ... } } class C extends A<C> { public void calcFoo() { foo=... whatever ... } } This appears to work but it looks pretty ugly. For one thing, I get warnings on "class A". The compiler says that A is generic and I should specify the type. I guess it wants me to say "class A". But what would I put in for x? I think I could get stuck in an infinite loop here. It seems weird to write "class B extends A", but this causes no complaints, so maybe that's just fine. Is this the right way to do it? Is there a better way?

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• PHP Error Form - Leave Contents of Form on Redirect

  - by user1371500

  I have a simple login form in which if an error occurs such as wrong password, I need it to be able to remember the username which was entered. Would I Go about doing this PHP or Javascript as I am not allowed to use JQuery. My current PHP - (Not Including the HTML Form) <?php //MySQl Connection mysql_connect("localhost", "root", "") or die(mysql_error()); mysql_select_db("clubresults") or die(mysql_error()); //Initiates New Session - Cookie session_start(); // Start a new session // Get the data passed from the form $username = $_POST['username']; $password = md5($_POST['pass']); // Do some basic sanitizing $username = mysql_real_escape_string($username); $password = mysql_real_escape_string($password); //Performs SQL Query to retrieve Login Details from DB $sql = "select * from admin_passwords where username = '$username' and password = '$password'"; $result = mysql_query($sql) or die ( mysql_error() ); //Assigns a Variable Count to 0 $count = 0; //Exectues a loop to increment on Successful Login while ($line = mysql_fetch_assoc($result)) { $count++; } //If count is equal to 1 Redirect user to the Members Page and Set Cookie if ($count == 1) { $_SESSION['loggedIn'] = "true"; header("Location: members.php"); // This is wherever you want to redirect the user to } else { //Else Echo that login was a failure. die('Login Failed. <a href=login.php>Click Here to Try Again</a>'); } ?> Any help would be appreciated. Cheers

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• multiplying all elements in an array by an outside number?

  - by prodo

  I need to multiple all the values in an array by 3000 which in turn would create a new array that I will use to subtract from another array. I've tried to create a separate method that would do that for me but all I got back in the multiplied array was a bunch of numbers and symbols strangely? here is the code that I wrote public static void main(String[] args) { int numberOfTaxpayers = Integer.parseInt(JOptionPane.showInputDialog("Enter how many users you would like to calculate taxes for: "); int[] usernumChild = new int[numberOfTaxPayers]; for (int i = 0; i < usernumChild.length; i++) { usernumChild[i] = Integer.parseInt(JOptionPane.showInputDialog("Enter number of children for user "+ (i+1) +": ")); }//this for loop finds out the number of children per user so we can later multiply each input by 3000 to create an array that determine dependency exemption for each user int[] depndExemp = multiply(usernumChild, 3000);//this was the calling of the multiply method... somewhere here is the error!! }//end main method public static int[] multiply(int[] children, int number) { int array[] = new int[children.length]; for( int i = 0; i < children.length; i++) { children[i] = children[i] * number; }//end for return array; }//this is the method that I was shown in a previous post on how to create return an array in this the dependency exemption array but when I tested this by printing out the dependency array all I received were a jumble of wrong numbers.

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• php weird bug where an array is not an array !

  - by iko

  I've been going mad trying to figure out why an array would not be an array in php. For a reason I can't understand I have a bug in a smarty class. The code is this : $compiled_tags = array(); for ($i = 0, $for_max = count($template_tags); $i < $for_max; $i++) { $this->_current_line_no += substr_count($text_blocks[$i], "\n"); // I tried array push instead to see // bug is here array_push($compiled_tags,$this->_compile_tag($template_tags[$i])); //$compiled_tags[] = $this->_compile_tag($template_tags[$i]); $this->_current_line_no += substr_count($template_tags[$i], "\n"); } the error message is Warning: array_push() expects parameter 1 to be array, integer given in .... OR before with [] Warning: Cannot use a scalar value as an array in .... I trying a var_debug on $compiled_tags and as soon I enter the for loop is not an array anymore but an integer. I tried renaming the variable, but same problem. I'm sure is something simple that I missed but I can't figure it out. Any help is (as always) welcomed !

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• Learning Java and logic using debugger. Did I cheat?

  - by centr0

  After a break from coding in general, my way of thinking logically faded (as if it was there to begin with...). I'm no master programmer. Intermediate at best. I decided to see if i can write an algorithm to print out the fibonacci sequence in Java. I got really frustrated because it was something so simple, and used the debugger to see what was going on with my variables. solved it in less than a minute with the help of the debugger. Is this cheating? When I read code either from a book or someone else's, I now find that it takes me a little more time to understand. If the alghorithm is complex (to me) i end up writing notes as to whats going on in the loop. A primitive debugger if you will. When you other programmers read code, do you also need to write things down as to whats the code doing? Or are you a genius and and just retain it?

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• How to get the parameter names of an object's constructors (reflection)?

  - by Tom

  Say I somehow got an object reference from an other class: Object myObj = anObject; Now I can get the class of this object: Class objClass = myObj.getClass(); Now, I can get all constructors of this class: Constructor[] constructors = objClass.getConstructors(); Now, I can loop every constructor: if (constructors.length > 0) { for (int i = 0; i < constructors.length; i++) { System.out.println(constructors[i]); } } This is already giving me a good summary of the constructor, for example a constructor public Test(String paramName) is shown as public Test(java.lang.String) Instead of giving me the class type however, I want to get the name of the parameter.. in this case "paramName". How would I do that? I tried the following without success: if (constructors.length > 0) { for (int iCon = 0; iCon < constructors.length; iCon++) { Class[] params = constructors[iCon].getParameterTypes(); if (params.length > 0) { for (int iPar = 0; iPar < params.length; iPar++) { Field fields[] = params[iPar].getDeclaredFields(); for (int iFields = 0; iFields < fields.length; iFields++) { String fieldName = fields[i].getName(); System.out.println(fieldName); } } } } } Unfortunately, this is not giving me the expected result. Could anyone tell me how I should do this or what I am doing wrong? Thanks!

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