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  • PHP syntax for postgresql Mixed-case table names

    - by yam
    I have a code below: <?php require "institution.php" /* in this portion, query for database connection is executed, and */ $institution= $_POST['institutionname']; $sCampID = 'SELECT ins_id FROM institution where ins_name= '$institution' '; $qcampID = pg_query($sCampID) or die("Error in query: $query." . pg_last_error($connection)); /* this portion outputs the ins_id */ ?> My database before has no mixed-case table names, that's why when I run this query, it shows no error at all. But because I've changed my database for some reasons, and it contains now mixed-case table names, i have to change the code above into this one: $sCampID = 'SELECT ins_id FROM "Institution" where ins_name= '$institution' '; where the Institution has to be double quoted. The query returned parse error. When i removed this portion: where ins_name= '$institution', no error occured. My question is how do I solve this problem where the table name which contains a mixed-case letter and a value stored in a variable ($institution in this case) will be combined in a single select statement? Your answers and suggestions will be very much appreciated.

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  • Passing $_GET or $_POST data to PHP script that is run with wget

    - by Matt
    Hello, I have the following line of PHP code which works great: exec( 'wget http://www.mydomain.com/u1.php /dev/null &' ); u1.php acts to do various types of maintenance on my server and the above command makes it happen in the background. No problems there. But I need to pass variable data to u1.php before it's executed. I'd like to pass POST data preferably, but could accommodate GET or SESSION data if POST isn't an option. Basically the type of data being passed is user-specific and will vary depending on who is logged in to the site and triggering the above code. I've tried adding the GET data to the end of the URL and that didn't work. So how else might I be able to send the data to u1.php? POST data preferred, SESSION data would work as well (but I tried this and it didn't pick up the logged in user's session data). GET would be a last resort. Thanks!

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  • Forms blank when rendering a partial when using a collection of objects. Help!

    - by dustmoo
    Alright, I know my title is a little obscure but it best describes the problem I am having. Essentially, I have a list of users, and want to be able to edit their information in-line using AJAX. Since the users are showing up in rows, I am using a partial to render the data and the forms (which will be hidden initially by the ajax), however, when the rows are rendered currently only the last item has it's form's fields populated. I suspect this has something to do with the fact that all the form fields have the same id's and it is confusing the DOM. But I don't know how to make sure the id's are unique. Here is a small example: In my view: <%= render :partial => 'shared/user', :collection => @users %> My partial (broke down to just the form) note that I am using the local variable "user" <% form_for user, :html => {:multipart => true} do |f| -%> <%= f.label :name, "Name*" %> <%= f.text_field :title, :class => "input" %> <%= f.label :Address, "Address" %> <%= f.text_field :address, :class => "input" %> <%= f.label :description, "Description*" %> <%= f.text_area :description, :class => "input" %> <% end -%> When the html is rendered each form has a unique id (for the id of the user) but the elements themselves all have the same id, and only the last user form is actually getting populated with values. Does anyone have any ideas?? :) Thanks in advance!

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  • PNG's In Mac on Java cause massive CPU usage

    - by alexganose
    Hey, I've been having this problem for a while now and I was hoping someone could help. I make small games using Java on Mac OSX 1.6.3 and if I use PNG's as the image format my CPU usage by Java skyrockets to say 50% (on a very small 2D game). However if I use GIF as the format my CPU usage by Java stays constant at 10% which is reasonable. What is causing this problem?? It occurs on every game I develop using PNG's so I always just switch to GIF's. The problem is now that i need to use a PNG for its variable alpha properties rather than just plain transparency. This is not available using GIF's. The problem is present on Java SE 6 and previous versions. I am using an early 2009 Mac Book Pro 15". The problem does not occur on a Windows PC running the same game. The CPU usage due to Java using PNG's on a Windows PC (I have tried XP, Vista and 7) is always constantly low at ~10%. Any help would be greatly appreciated. Thanks :)

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  • How to have variables with dynamic data types in Java?

    - by Nazgulled
    Hi, I need to have a UserProfile class that it's just that, a user profile. This user profile has some vital user data of course, but it also needs to have lists of messages sent from the user friends. I need to save these messages in LinkedList, ArrayList, HashMap and TreeMap. But only one at a time and not duplicate the message for each data structure. Basically, something like a dynamic variable type where I could pick the data type for the messages. Is this, somehow, possible in Java? Or my best approach is something like this? I mean, have 2 different classes (for the user profile), one where I host the messages as Map<K,V> (and then I use HashMap and TreeMap where appropriately) and another class where I host them as List<E> (and then I use LinkedList and ArrayList where appropriately). And probably use a super class for the UserProfile so I don't have to duplicate variables and methods for fields like data, age, address, etc... Any thoughts?

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  • What is the best approach to embed mp4 for the iPhone without using JavaScript?

    - by usingtechnology
    I am trying to troubleshoot this code and am running into a dead-end, so I thought I would ask my first question here. I have three questions: 1) What is the best approach to embed an mp4 for an iPhone specific view, preferably without using Javascript? 2) Are there any preferred practices to debug code on an iPhone? 3) Can anyone tell me what is wrong with my specific code below? I should mention upfront that the variable $fileName does indeed contain the correct info, I've just omitted that portion of the code. Also, the poster image does flicker for a brief moment before I receive the greyed out, broken QuickTime image so that is an indication that this is partially working. Code: <object width="448" height="335" classid="clsid:02BF25D5-8C17-4B23-BC80-D3488ABDDC6B" codebase="http://www.apple.com/qtactivex/qtplugin.cab"> <param name="src" value="/libraries/images/$fileName.jpg" /> <param name="href" value="/libraries/media/$fileName.mp4" /> <param name="target" value="myself" /> <param name="controller" value="true" /> <param name="autoplay" value="false" /> <param name="scale" value="aspect" /> <embed src="/libraries/images/$fileName.jpg" href="/libraries/media/$fileName.mp4" type="video/mp4" target="myself" width="448" height="335" scale="aspect" controller="false" autoplay="false"> </embed> </object>

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  • Cannot implicitly convert type ...

    - by Newbie
    I have the following function public Dictionary<DateTime, object> GetAttributeList( EnumFactorType attributeType ,Thomson.Financial.Vestek.Util.DateRange dateRange) { DateTime startDate = dateRange.StartDate; DateTime endDate = dateRange.EndDate; return (( //Step 1: Iterate over the attribute list and filter the records by // the supplied attribute type from assetAttribute in AttributeCollection where assetAttribute.AttributeType.Equals(attributeType) //Step2:Assign the TimeSeriesData collection into a temporary variable let timeSeriesList = assetAttribute.TimeSeriesData //Step 3: Iterate over the TimeSeriesData list and filter the records by // the supplied date from timeSeries in timeSeriesList.ToList() where timeSeries.Key >= startDate && timeSeries.Key <= endDate //Finally build the needed collection select new AssetAttribute() { TimeSeriesData = PopulateTimeSeriesData(timeSeries.Key, timeSeries.Value) }).ToList<AssetAttribute>().Select(i => i.TimeSeriesData)); } private Dictionary<DateTime, object> PopulateTimeSeriesData(DateTime dateTime, object value) { Dictionary<DateTime, object> timeSeriesData = new Dictionary<DateTime, object>(); timeSeriesData.Add(dateTime, value); return timeSeriesData; } Error:Cannot implicitly convert type 'System.Collections.Generic.IEnumerable' to 'System.Collections.Generic.Dictionary'. An explicit conversion exists (are you missing a cast?) Using C#3.0 Please help

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  • How to run a javascript function before postback of asp.net button?

    - by Curtis White
    I'm using Javascript to create a DIV element and open up a new page by using onclientclick. This works great. Now, I need to write to it from the server side and this element must be created before it is posted back. How do I get the javascript to execute before the postback? Currently, I have to press the button twice because the element doesn't exist to write too on the first click. To be clear, I need this to execute before the "OnClick" of the button. Update: It looks like the Javascript function is called before the postback but the element is not updated until I run the second postback. Hmm Update: Unfortunately it is a bit more complicated then this. I'm creating a div tag in javascript to open a new window. Inside the div tag, I'm using a databinding syntax <%=Preview% so that I can get access to this element on the server side. From the server side, I'm injecting the code. I'm thinking this may be a chicken-egg problem but not sure. UPDATE! It is not the Javascript not running first. It is the databinding mechanism which is reading the blank variable before I'm able to set it. Hmm

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  • Writing own Unix shell in C - Problems with PATH and execv

    - by user1287523
    I'm writing my own shell in C. It needs to be able to display the users current directory, execute commands based on the full path (must use execv), and allow the user to change the directory with cd. This IS homework. The teacher only gave us a basic primer on C and a very brief skeleton on how the program should work. Since I'm not one to give up easily I've been researching how to do this for three days, but now I'm stumped. This is what I have so far: Displays the user's username, computername, and current directory (defaults to home directory). Prompts the user for input, and gets the input Splits the user's input by " " into an array of arguments Splits the environment variable PATH by ":" into an array of tokens I'm not sure how to proceed from here. I know I've got to use the execv command but in my research on google I haven't really found an example I understand. For instance, if the command is bin/ls, how does execv know the display all files/folders from the home directory? How do I tell the system I changed the directory? I've been using this site a lot which has been helpful: http://linuxgazette.net/111/ramankutty.html but again, I'm stumped. Thanks for your help. Let me know if I should post some of my existing code, I'm wasn't sure if it was necessary though.

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  • iPhone AES encryption issue

    - by Dilshan
    Hi, I use following code to encrypt using AES. - (NSData*)AES256EncryptWithKey:(NSString*)key theMsg:(NSData *)myMessage { // 'key' should be 32 bytes for AES256, will be null-padded otherwise char keyPtr[kCCKeySizeAES256 + 1]; // room for terminator (unused) bzero(keyPtr, sizeof(keyPtr)); // fill with zeroes (for padding) // fetch key data [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; NSUInteger dataLength = [myMessage length]; //See the doc: For block ciphers, the output size will always be less than or //equal to the input size plus the size of one block. //That's why we need to add the size of one block here size_t bufferSize = dataLength + kCCBlockSizeAES128; void* buffer = malloc(bufferSize); size_t numBytesEncrypted = 0; CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding, keyPtr, kCCKeySizeAES256, NULL /* initialization vector (optional) */, [myMessage bytes], dataLength, /* input */ buffer, bufferSize, /* output */ &numBytesEncrypted); if (cryptStatus == kCCSuccess) { //the returned NSData takes ownership of the buffer and will free it on deallocation return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted]; } free(buffer); //free the buffer; return nil; } However the following code chunk returns null if I tried to print the encryptmessage variable. Same thing applies to decryption as well. What am I doing wrong here? NSData *encrData = [self AES256EncryptWithKey:theKey theMsg:myMessage]; NSString *encryptmessage = [[NSString alloc] initWithData:encrData encoding:NSUTF8StringEncoding]; Thank you

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  • multi-threading in MFC

    - by kiddo
    Hello all,in my application there is a small part of function,in which it will read files to get some information,the number of filecount would be utleast 50,So I thought of implementing threading.Say if the user is giving 50 files,I wanted to separate it as 5 *10, 5 thread should be created,so that each thread can handle 10 files which can speed up the process.And also from the below code you can see that some variables are common.I read some articles about threading and I am aware that only one thread should access a variable/contorl at a me(CCriticalStiuation can be used for that).For me as a beginner,I am finding hard to imlplement what I have learned about threading.Somebody please give me some idea with code shown below..thanks in advance file read function:// void CMyClass::GetWorkFilesInfo(CStringArray& dataFilesArray,CString* dataFilesB, int* check,DWORD noOfFiles,LPWSTR path) { CString cFilePath; int cIndex =0; int exceptionInd = 0; wchar_t** filesForWork = new wchar_t*[noOfFiles]; int tempCheck; int localIndex =0; for(int index = 0;index < noOfFiles; index++) { tempCheck = *(check + index); if(tempCheck == NOCHECKBOX) { *(filesForWork+cIndex) = new TCHAR[MAX_PATH]; wcscpy(*(filesForWork+cIndex),*(dataFilesB +index)); cIndex++; } else//CHECKED or UNCHECKED { dataFilesArray.Add(*(dataFilesB+index)); *(check + localIndex) = *(check + index); localIndex++; } } WorkFiles(&cFilePath,dataFilesArray,filesForWork, path, cIndex); dataFilesArray.Add(cFilePath); *(check + localIndex) = CHECKED; }

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  • Permission Denied error in IE when closing popups

    - by Kenia
    Hi everyone! I have a simple web testing application which is supposed to open and close several popups by itself (without user interaction). For this purpose i have a javascript function to access the variable where the popup reference is stored and close it if it´s not null, fairly simple. However I get random errors in IE (in FF it works as expected, all popups are closed correctly) like Message: No such interface supported Line: 86 Char: 3 Code: 0 URI: http://10.10.0.61:10000/savmailer/adm/tests/common_tests_code.js and Message: Permission denied Line: 86 Char: 3 Code: 0 URI: http://10.10.0.61:10000/savmailer/adm/tests/common_tests_code.js The line 86 references exactly the point at which I do popup.close(); in the following function function closePopupWindow(popup){ if (popup != null) { popup.close(); popup = null; } } I have googled and it seems this permission denied error is quite common to come through among IE developers, however there´s no clear solution for it, it´s just a matter of changing the code slightly "to please" IE, so to speak. However i have no idea how to change mine since it´s just 3 lines! Tried also to change the security browser settings by adding my domain to the trusted zone, but nothing, doesn't help either. If anyone has any helpful idea or notices something i might be forgetting, please, reply to this! Thanks in advance, Kenia

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  • C++ template type deduction problem

    - by hamishmcn
    motivation: I would like to create a utility class so that instead of having to write: if( someVal == val1 || someVal == val2 || someVal == val3 ) I could instead write: if( is(someVal).in(val1, val2, val3) ) which is much closer to the mathematical 'a is an element of (b,c,d)' and also would save on a lot of typing when the variable name 'someVal' is long. Here is the code I have so far (for 2 and 3 values): template<class T> class is { private: T t_; public: is(T t) : t_(t) { } bool in(const T& v1, const T& v2) { return t_ == v1 || t_ == v2; } bool in(const T& v1, const T& v2, const T& v3) { return t_ == v1 || t_ == v2 || t_ == v3; } }; However it fails to compile if I write: is(1).in(3,4,5); instead I have to write is<int>(1).in(3,4,5); Which isn't too bad, but it would be better if somehow the compiler could figure out that the type is int with out me having to explicitly specify it. Is there anyway to do this or I am stuck with specifying it explicitly?

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  • In Python, how to make data members visible to subclasses if not known when initializing an object ?

    - by LB
    The title is a bit long, but it should be pretty straightforward for someone well-aware of python. I'm a python newbie. So, maybe i'm doing things in the wrong way. Suppose I have a class TreeNode class TreeNode(Node): def __init__(self, name, id): Node.__init__(self, name, id) self.children = [] and a subclass with a weight: class WeightedNode(TreeNode): def __init__(self,name, id): TreeNode.__init__(self, name, id) self.weight = 0 So far, i think I'm ok. Now, I want to add an object variable called father in TreeNode so that WeightedNode has also this member. The problem is that I don't know when initializing the object who is going to be the father. I set the father afterwards with this method in TreeNode : def set_father(self, father_node): self.father = father_node The problem is then when i'm trying to access self.father in Weighted: print 'Name %s Father %s '%(self.name, self.father.name) I obtain: AttributeError: WeightedNode instance has no attribute 'father' I thought that I could make father visible by doing something in TreeNode.__init__ but i wasn't able to find what. How can i do that ? Thanks.

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  • How do I pass a value to a method in Objective C

    - by user268124
    I'm new to Obj-C and I have run in to a very, very basic mental block that's making me feel a little stupid. I want to pass a variable from one method to another in an purely objective-C way. So far I'm stuck and have resorted to writing it in C. In C it goes as follows; //detect the change in the segmented switch so we can; change text - (IBAction)switchChanged:(id)sender { NSLog(@"Switch change detected"); //grab the info from the sender UISegmentedControl *selector = sender; //grab the selected segment info from selector. This returns a 0 or a 1. int selectorIndex = [selector selectedSegmentIndex]; changeText (selectorIndex); } int changeText (int selectorPosition) { NSLog(@"changeText received a value. Selector position is %d", selectorPosition); //Idea is to receive a value from the segmented controler and change the screen text accordingly return 0; } This works perfectly well, but I want to learn how to do this with objects and messages. How would I rewrite these two methods to do this? Cheers Rich

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  • Reference problem when returning an object from array in PHP

    - by avastreg
    I've a reference problem; the example should be more descriptive than me :P I have a class that has an array of objects and retrieve them through a key (string), like an associative array: class Collection { public $elements; function __construct() { $this->elements = array(); } public function get_element($key) { foreach($this->elements as $element) { if ($element->key == $key) { return $element; break; } } return null; } public function add_element ($element) { $this->elements[] = $element; } } Then i have an object (generic), with a key and some variables: class Element { public $key; public $another_var; public function __construct($key) { $this->key = $key; $this->another_var = "default"; } } Now, i create my collection: $collection = new Collection(); $collection->add_element(new Element("test1")); $collection->add_element(new Element("test2")); And then i try to change variable of an element contained in my "array": $element = $collection->get_element("test1"); $element->another_var = "random_string"; echo $collection->get_element("test1")->another_var; Ok, the output is random_string so i know that my object is passed to $element in reference mode. But if i do, instead: $element = $collection-get_element("test1"); $element = null; //or $element = new GenericObject(); $element-another_var = "bla"; echo $collection-get_element("test1")-another_var; the output is default like if it lost the reference. So, what's wrong? I have got the references to the variables of the element and not to the element itself? Any ideas?

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  • Iphone -- maintaining a list of strings and a corresponding typedef enum

    - by William Jockusch
    Suppose I have the following: typedef enum functionType {ln, sin, sqrt} functionType; NSArray *functions = [NSArray arrayWithObjects: @"ln", @"sin", @"sqrt", nil]; Suppose further that *functions will not change at runtime. Question -- is there any way to set up a single structure which updates both of these? So that I only have to keep track of one list, instead of two. To explain what is going on -- the idea is that string input from the user will be stored in a variable of type functionType. Later on, I will have code like this: double valueOfFunction: (functionType) function withInput: (double) input switch (function) { case ln: return ln(input); case sin: return sin(input); case sqrt: return sqrt(input); //etc . . . could grow to include a lot of functions. } And valueOfFunction needs to be fast. So I don't want to be doing string comparisons there.

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  • Please help me optimize my Python code

    - by Haidon
    Beginner here! Forgive me in advance for raising what is probably an incredibly simple problem. I've been trying to put together a Python script that runs multiple find-and-replace actions and a few similar things on a specified plain-text file. It works, but from a programming perspective I doubt it works well. How would I best go about optimizing the actions made upon the 'outtext' variable? At the moment it's basically doing a very similar thing four times over... import binascii import re import struct import sys infile = sys.argv[1] charenc = sys.argv[2] outFile=infile+'.tex' findreplace = [ ('TERM1', 'TERM2'), ('TERM3', 'TERM4'), ('TERM5', 'TERM6'), ] inF = open(infile,'rb') s=unicode(inF.read(),charenc) inF.close() # THIS IS VERY MESSY. for couple in findreplace: outtext=s.replace(couple[0],couple[1]) s=outtext for couple in findreplace: outtext=re.compile('Title: (.*)', re.I).sub(r'\\title'+ r'{\1}', s) s=outtext for couple in findreplace: outtext=re.compile('Author: (.*)', re.I).sub(r'\\author'+ r'{\1}', s) s=outtext for couple in findreplace: outtext=re.compile('Date: (.*)', re.I).sub(r'\\date'+ r'{\1}', s) s=outtext # END MESSY SECTION. outF = open(outFile,'wb') outF.write(outtext.encode('utf-8')) outF.close()

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  • Using a single texture image unit with multiple sampler uniforms

    - by bcrist
    I am writing a batching system which tracks currently bound textures in order to avoid unnecessary glBindTexture() calls. I'm not sure if I need to keep track of which textures have already been used by a particular batch so that if a texture is used twice, it will be bound to a different TIU for the second sampler which requires it. Is it acceptable for an OpenGL application to use the same texture image unit for multiple samplers within the same shader stage? What about samplers in different shader stages? For example: Fragment shader: ... uniform sampler2D samp1; uniform sampler2D samp2; void main() { ... } Main program: ... glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, tex_id); glUniform1i(samp1_location, 0); glUniform1i(samp2_location, 0); ... I don't see any reason why this shouldn't work, but what about if the shader program also included a vertex shader like this: Vertex shader: ... uniform sampler2D samp1; void main() { ... } In this case, OpenGL is supposed to treat both instances of samp1 as the same variable, and exposes a single location for them. Therefore, the same texture unit is being used in the vertex and fragment shaders. I have read that using the same texture in two different shader stages counts doubly against GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS but this would seem to contradict that. In a quick test on my hardware (HD 6870), all of the following scenarios worked as expected: 1 TIU used for 2 sampler uniforms in same shader stage 1 TIU used for 1 sampler uniform which is used in 2 shader stages 1 TIU used for 2 sampler uniforms, each occurring in a different stage. However, I don't know if this is behavior that I should expect on all hardware/drivers, or if there are performance implications.

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  • How to break out from nested doseqs

    - by fizbin
    Hi, I have a question regarding nested doseq loops. In the start function, once I find an answer I set the atom to true, so that the outer loop validation with :while fails. However it seems that it doesn't break it, and the loops keep on going. What's wrong with it? I am also quite confused with the usage of atoms, refs, agents (Why do they have different names for the update functions when then the mechanism is almost the same?) etc. Is it okay to use an atom in this situation as a flag? Obviously I need a a variable like object to store a state. (def pentagonal-list (map (fn [a] (/ (* a (dec (* 3 a))) 2)) (iterate inc 1))) (def found (atom false)) (defn pentagonal? [a] (let [y (/ (inc (Math/sqrt (inc (* 24 a)))) 6) x (mod (* 10 y) 10)] (if (zero? x) true false))) (defn both-pent? [a b] (let [sum (+ b a) diff (- a b)] (if (and (pentagonal? sum) (pentagonal? diff)) true false))) (defn start [] (doseq [x pentagonal-list :while (false? @found)] (doseq [y pentagonal-list :while (<= y x)] (if (both-pent? x y) (do (reset! found true) (println (- x y)))))))

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  • Why aren't my threads start at the same time? Java

    - by Ada
    Hi, I have variable number of threads which are used for parallel downloading. I used this, for(int i = 0; i< sth; i++){ thrList.add(new myThread (parameters)); thrList.get(i).start(); thrList.get(i).join(); } I don't know why but they wait for each other to complete. When using threads, I am supposed get mixed print outs, since right then there are several threads running that code. However, when I print them out, they are always in order and one thread waits for the previous one to finish first. I only want them to join the main thread, not wait for each other. I noticed that when I measured time while downloading in parallel. How can I fix this? Why are they doing it in order? In my .java, there is MyThread class with run and there is Downloader class with static methods and variables. Would they be the cause of this? The static methods and variables? How can I fix this problem?

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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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  • whether rand_r is real thread safe?

    - by terry
    Well, rand_r function is supposed to be a thread safe function. However, by its implementation, I cannot believe it could make itself not change by other threads. Suppose that two threads will invoke rand_r in the same time with the same variable seed. So read-write race will occur. The code rand_r implemented by glibc is listed below. Anybody knows why rand_r is called thread safe? int rand_r (unsigned int *seed) { unsigned int next = *seed; int result; next *= 1103515245; next += 12345; result = (unsigned int) (next / 65536) % 2048; next *= 1103515245; next += 12345; result <<= 10; result ^= (unsigned int) (next / 65536) % 1024; next *= 1103515245; next += 12345; result <<= 10; result ^= (unsigned int) (next / 65536) % 1024; *seed = next; return result; }

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  • How to prevent VC++ 9 linker from linking unnecessary global variables?

    - by sharptooth
    I'm playing with function-level linking in VC++. I've enabled /OPT:REF and /OPT:ICF and the linker is happy to eliminate all unused functions. Not so with variables. The following code is to demonstrate the problem only, I fully understand that actually having code structured that way is suboptimal. //A.cpp SomeType variable1; //B.cpp extern SomeType variable1; SomeType variable2; class ClassInB { //actually uses variable1 }; //C.cpp extern SomeType variable2; class ClassInC { //actually uses variable2; }; All those files are compiled into a static lib. The consumer project only uses ClassInC and links to the static library. Now comes the VC++ 9 linker. First the linker sees that C.obj references variable2 and includes B.obj. B.obj references variable1, so it includes A.obj. Then the unreferenced stuff elimination phase starts. It removes all functions in A.obj and B.obj, but not the variables. Both variable and variable2 are preserved together with their static initializers and deinitializers. That inflates the image size and introduces a delay for running the initializers and deinitializes. The code above is oversimplified, in actual code I really can't move variable2 into C.cpp easily. I could put it into a separate .cpp file, but that looks really dumb. Is there any better option to resolve the problem with Visual C++ 9?

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  • Looping through a method without for/foreach/while

    - by RichK
    Is there a way of calling a method/lines of code multiple times not using a for/foreach/while loop? For example, if I were to use to for loop: int numberOfIterations = 6; for(int i = 0; i < numberOfIterations; i++) { DoSomething(); SomeProperty = true; } The lines of code I'm calling don't use 'i' and in my opinion the whole loop declaration hides what I'm trying to do. This is the same for a foreach. I was wondering if there's a looping statement I can use that looks something like: do(6) { DoSomething(); SomeProperty = true; } It's really clear that I just want to execute that code 6 times and there's no noise involving index instantiating and adding 1 to some arbitrary variable. As a learning exercise I have written a static class and method: Do.Multiple(int iterations, Action action) Which works but scores very highly on the pretentious scale and I'm sure my peers wouldn't approve. I'm probably just being picky and a for loop is certainly the most recognisable, but as a learning point I was just wondering if there (cleaner) alternatives. Thanks. (I've had a look at this thread, but it's not quite the same) http://stackoverflow.com/questions/2248985/using-ienumerable-without-foreach-loop

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