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  • insert multiple rows into database from arrays

    - by Mark
    Hi, i need some help with inserting multiple rows from different arrays into my database. I am making the database for a seating plan, for each seating block there is 5 rows (A-E) with each row having 15 seats. my DB rows are seat_id, seat_block, seat_row, seat_number, therefore i need to add 15 seat_numbers for each seat_row and 5 seat_rows for each seat_block. I mocked it up with some foreach loops but need some help turning it into an (hopefully single) SQL statement. $blocks = array("A","B","C","D"); $seat_rows = array("A","B","C","D","E"); $seat_nums = array("1","2","3","4","5","6","7","8","9","10","11","12","13","14","15"); foreach($blocks as $block){ echo "<br><br>"; echo "Block: " . $block . " - "; foreach($seat_rows as $rows){ echo "Row: " . $rows . ", "; foreach($seat_nums as $seats){ echo "seat:" . $seats . " "; } } } Maybe there's a better way of doing it instead of using arrays? i just want to avoid writing an SQL statement that is over 100 lines long ;) (im using codeigniter too if anyone knows of a CI specific way of doing it but im not too bothered about that)

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  • Optimize Duplicate Detection

    - by Dave Jarvis
    Background This is an optimization problem. Oracle Forms XML files have elements such as: <Trigger TriggerName="name" TriggerText="SELECT * FROM DUAL" ... /> Where the TriggerText is arbitrary SQL code. Each SQL statement has been extracted into uniquely named files such as: sql/module=DIAL_ACCESS+trigger=KEY-LISTVAL+filename=d_access.fmb.sql sql/module=REP_PAT_SEEN+trigger=KEY-LISTVAL+filename=rep_pat_seen.fmb.sql I wrote a script to generate a list of exact duplicates using a brute force approach. Problem There are 37,497 files to compare against each other; it takes 8 minutes to compare one file against all the others. Logically, if A = B and A = C, then there is no need to check if B = C. So the problem is: how do you eliminate the redundant comparisons? The script will complete in approximately 208 days. Script Source Code The comparison script is as follows: #!/bin/bash echo Loading directory ... for i in $(find sql/ -type f -name \*.sql); do echo Comparing $i ... for j in $(find sql/ -type f -name \*.sql); do if [ "$i" = "$j" ]; then continue; fi # Case insensitive compare, ignore spaces diff -IEbwBaq $i $j > /dev/null # 0 = no difference (i.e., duplicate code) if [ $? = 0 ]; then echo $i :: $j >> clones.txt fi done done Question How would you optimize the script so that checking for cloned code is a few orders of magnitude faster? System Constraints Using a quad-core CPU with an SSD; trying to avoid using cloud services if possible. The system is a Windows-based machine with Cygwin installed -- algorithms or solutions in other languages are welcome. Thank you!

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  • C# form - checkboxes do not respond to plus/minus keys - easy workaround?

    - by Scott
    On forms created with pre dotNET VB and C++ (MFC), a checkbox control responded to the plus/minus key without custom programming. When focus was on the checbox control, pressing PLUS would check the box, no matter what the previous state (checked/unchecked), while pressing MINUS would uncheck it, no matter the previous state. C# winform checkboxes do not seem to exhibit this behavior. Said behavior was very, very handy for automation, whereby the automating program would set focus to a checkbox control and issue a PLUS or MINUS to check or uncheck it. Without this capability, that cannot be done, as the automation program (at least the one I am using) is unable to query the current state of the checkbox (so it can decide whether to issue a SPACE key to toggle the state to the desired one). I've gone over the properties of a checkbox in the Visual Studio 2008 IDE and could not find anything that would restore/enable response to PLUS/MINUS. Since I am in control of the sourcecode for the WinForms in question, I could replace all checkbox controls with a custom checkbox control, but blech, I'd like to avoid that - heck, I don't think I could even consider that given the amount of refactoring that would need to be done. So the bottom line is: does anyone know of a way to get this behavior back more easily than a coding change?

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  • Using "as bool?" instead of "object something = ViewState["hi"]"

    - by Programmin Tool
    So I'm going through old code (2.0) and I came across this: object isReviewingValue = ViewState["IsReviewing"]; if (isReviewingValue is bool) { return (bool)isReviewingValue; } My first thought was to us the "as" keyword to avoid the unneeded (bool)isReviewingValue; But "as" only works with non value types. No problem, I just went ahead and did this: bool? isReviewingValue= ViewState["IsReviewing"] as bool?; if (isReviewingValue.HasValue) { return isReviewingValue.Value; } Question is: Besides looking a bit more readable, is this in fact better? EDIT: So this is getting more interesting. I decided to test it using a simple stopwatch and turns out that the second is much faster... Which after reading some of the responses here I didn't expect at all. I was thinking for sure my way was much slower. Tell me what I did wrong: public Stopwatch AsRun() { Stopwatch watch = new Stopwatch(); watch.Start(); for (Int32 loopCounter = 0; loopCounter < 10000; loopCounter++) { Boolean? test = true as Boolean?; if (test.HasValue) { Boolean something = test.Value; } } watch.Stop(); return watch; } public Stopwatch ObjectIsRun() { Stopwatch watch = new Stopwatch(); watch.Start(); for (Int32 loopCounter = 0; loopCounter < 10000; loopCounter++) { Object test = true; if (test is Boolean) { Boolean something = (Boolean)test; } } watch.Stop(); return watch; } Every time I run these methods against each other, the AsRun is twice as fast.

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  • initalizing two pointers to same value in "for" loop

    - by MCP
    I'm working with a linked list and am trying to initalize two pointers equal to the "first"/"head" pointer. I'm trying to do this cleanly in a "for" loop. The point of all this being so that I can run two pointers through the linked list, one right behind the other (so that I can modify as needed)... Something like: //listHead = main pointer to the linked list for (blockT *front, *back = listHead; front != NULL; front = front->next) //...// back = back->next; The idea being I can increment front early so that it's one ahead, doing the work, and not incrementing "back" until the bottom of the code block in case I need to backup in order to modify the linked list... Regardless as to the "why" of this, in addition to the above I've tried: for (blockT *front = *back = listHead; /.../ for (blockT *front = listHead, blockT *back = listHead; /.../ I would like to avoid pointer to a pointer. Do I just need to initialize these before the loop? As always, thanks!

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  • C++, inject additional data in a method

    - by justik
    I am adding the new modul in some large library. All methods here are implemented as static. Let mi briefly describe the simplified model: typedef std::vector<double> TData; double test ( const TData &arg ) { return arg ( 0 ) * sin ( arg ( 1 ) + ...;} double ( * p_test ) ( const TData> &arg) = &test; class A { public: static T f1 (TData &input) { .... //some computations B::f2 (p_test); } }; Inside f1() some computations are perfomed and a static method B::f2 is called. The f2 method is implemented by another author and represents some simulation algorithm (example here is siplified). class B { public: static double f2 (double ( * p_test ) ( const TData &arg ) ) { //difficult algorithm working p_test many times double res = p_test(arg); } }; The f2 method has a pointer to some weight function (here p_test). But in my case some additional parameters computed in f1 for test() methods are required double test ( const TData &arg, const TData &arg2, char *arg3.... ) { } How to inject these parameters into test() (and so to f2) to avoid changing the source code of the f2 methods (that is not trivial), redesign of the library and without dirty hacks :-) ? The most simple step is to override f2 static double f2 (double ( * p_test ) ( const TData &arg ), const TData &arg2, char *arg3.... ) But what to do later? Consider, that methods are static, so there will be problems with objects. Thanks for your help.

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  • Using the JPA Criteria API, can you do a fetch join that results in only one join?

    - by Shaun
    Using JPA 2.0. It seems that by default (no explicit fetch), @OneToOne(fetch = FetchType.EAGER) fields are fetched in 1 + N queries, where N is the number of results containing an Entity that defines the relationship to a distinct related entity. Using the Criteria API, I might try to avoid that as follows: CriteriaBuilder builder = entityManager.getCriteriaBuilder(); CriteriaQuery<MyEntity> query = builder.createQuery(MyEntity.class); Root<MyEntity> root = query.from(MyEntity.class); Join<MyEntity, RelatedEntity> join = root.join("relatedEntity"); root.fetch("relatedEntity"); query.select(root).where(builder.equals(join.get("id"), 3)); The above should ideally be equivalent to the following: SELECT m FROM MyEntity m JOIN FETCH myEntity.relatedEntity r WHERE r.id = 3 However, the criteria query results in the root table needlessly being joined to the related entity table twice; once for the fetch, and once for the where predicate. The resulting SQL looks something like this: SELECT myentity.id, myentity.attribute, relatedentity2.id, relatedentity2.attribute FROM my_entity myentity INNER JOIN related_entity relatedentity1 ON myentity.related_id = relatedentity1.id INNER JOIN related_entity relatedentity2 ON myentity.related_id = relatedentity2.id WHERE relatedentity1.id = 3 Alas, if I only do the fetch, then I don't have an expression to use in the where clause. Am I missing something, or is this a limitation of the Criteria API? If it's the latter, is this being remedied in JPA 2.1 or are there any vendor-specific enhancements? Otherwise, it seems better to just give up compile-time type checking (I realize my example doesn't use the metamodel) and use dynamic JPQL TypedQueries.

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  • How to use CellRenderer for GregorianCalendar?

    - by HansDampf
    So I have been trying to use the example from Tutorial and change it so it fits my program. The getColumnValue method returns the object that holds the information that is supposed to be displayed. Is this the way to go or should it rather return the actual String to be displayed. I guess not because that way I would mix the presentation with the data, which I was trying to avoid. public class IssueTableFormat implements TableFormat<Appointment> { public int getColumnCount() { return 6; } public String getColumnName(int column) { if(column == 0) return "Datum"; else if(column == 1) return "Uhrzeit"; else if(column == 2) return "Nummer"; else if(column == 3) return "Name"; else if(column == 4) return "letzte Aktion"; else if(column == 5) return "Kommentar"; throw new IllegalStateException(); } public Object getColumnValue(Appointment issue, int column) { if(column == 0) return issue.getDate(); else if(column == 1) return issue.getDate(); else if(column == 2) return issue.getSample(); else if(column == 3) return issue.getSample(); else if(column == 4) return issue.getHistory(); else if(column == 5) return issue.getComment(); throw new IllegalStateException(); } } The column 0 and 1 contain a GregorianCalendar object, but I want column 0 to show the date and 1 to show the time. So I know using cellRenderers can help here. This is what I tried. public class DateRenderer extends DefaultTableCellRenderer { public DateRenderer() { super(); } public void setValue(Object value) { GregorianCalendar g =(GregorianCalendar) value; value=g.get(GregorianCalendar.HOUR); } } But the cell doesnt show anything, what is wrong here?

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  • How to enforce that HTTP client uses conditional requests for updates?

    - by Day
    In a (proper RMM level 3) RESTful HTTP API, I want to enforce the fact that clients should make conditional requests when updating resources, in order to avoid the lost update problem. What would be an appropriate response to return to clients that incorrectly attempt unconditional PUT requests? I note that the (abandoned?) mod_atom returns a 405 Method Not Allowed with an Allow header set to GET, HEAD (view source) when an unconditional update is attempted. This seems slightly misleading - to me this implies that PUT is never a valid method to attempt on the resource. Perhaps the response just needs to have an entity body explaining that If-Match or If-Unmodified-Since must be used to make the PUT request conditional in which case it would be allowed? Or perhaps a 400 Bad Request with a suitable explanation in the entity body would be a better solution? But again, this doesn't feel quite right because it's using a 400 response for a violation of application specific semantics when RFC 2616 says (my emphasis): The request could not be understood by the server due to malformed syntax. But than again, I think that using 400 Bad Request for application specific semantics is becoming a widely accepted pragmatic solution (citation needed!), and I'm just being overly pedantic.

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  • Problem with running totals in jquery

    - by rshivers
    I'm having an issue trying to get an accurate running total for my calculations. When you enter numbers into the input field I get an accurate total for that line item, but the grand total comes out to a higher number. Note that this is a dynamic form and that the id's will change depending on how many form fields I have added to the form. Also, I have it set to make the calculations onKeyUp for each input field instead of a calculate button. The code that calculates a single item is this: function calcLineItem(id) { var id = $(id).attr("id"); var Item1 = $("#Item1" + id).val(); var Item2 = $("#Item2" + id).val(); var Item3 = $("#Item3" + id).val(); function calcTotal(Item1, Item2, Item3){ var total; total = Math.round((Item1 * Item2) * Item3); return total; } $("#total" + id).text(calcTotal(Item1, Item2, Item3)); calcAllFields(); } This will give me the total of this particular input field. The function at the end, calcAllFields(), is supposed to do the calculations for all items in my form to give me the grand total of all input fields: function calcAllFields(id) { var id = $(id).attr("id"); $('#target1').text($("#total" + id).map(function() { var currentValue = parseFloat(document.getElementById("currentTotal").value); var newValue = parseFloat($("#total" + id).text()); var newTotal = currentValue + newValue; document.getElementById("currentTotal").value = newTotal; return newTotal; }).get().join()); } The variable currentTotal is getting its value from a hidden field on my form: <input type="hidden" id="currentTotal" value="0"> As I enter numbers a field the calculation for that line will be accurate, but the grand total will be inaccurate because the value for currentTotal will continue to increment with every key stroke I make in the input field. Any ideas on how to avoid this from happening?

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  • Delphi static method of a class returning property value

    - by mitko.berbatov
    I'm making a Delphi VCL application. There is a class TStudent where I have two static functions: one which returns last name from an array of TStudent and another one which returns the first name of the student. Their code is something like: class function TStudent.FirstNameOf(aLastName: string): string; var i : integer; begin for i := 0 to Length(studentsArray) - 1 do begin if studentsArray[i].LastName = aLastName then begin result := studentsArray[i].FirstName; Exit; end; end; result := 'no match was found'; end; class function TStudent.LastNameOf(aFirstName: string): string; var i : integer; begin for i := 0 to Length(studentsArray) - 1 do begin if studentsArray[i].FirstName = aFirstName then begin result := studentsArray[i].LastName; Exit; end; end; result := 'no match was found'; end; My question is how can I avoid writing almost same code twice. Is there any way to pass the property as parameter of the functions.

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  • c++ float subtraction rounding error

    - by Volkan Ozyilmaz
    I have a float value between 0 and 1. I need to convert it with -120 to 80. To do this, first I multiply with 200 after 120 subtract. When subtract is made I had rounding error. Let's look my example. float val = 0.6050f; val *= 200.f; Now val is 121.0 as I expected. val -= 120.0f; Now val is 0.99999992 I thought maybe I can avoid this problem with multiplication and division. float val = 0.6050f; val *= 200.f; val *= 100.f; val -= 12000.0f; val /= 100.f; But it didn't help. I have still 0.99 on my hand. Is there a solution for it? Edit: After with detailed logging, I understand there is no problem with this part of code. Before my log shows me "0.605", after I had detailed log and I saw "0.60499995946884155273437500000000000000000000000000" the problem is in different place.

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  • php memory how much is too much

    - by Rob
    I'm currently re-writing my site using my own framework (it's very simple and does exactly what I need, i've no need for something like Zend or Cake PHP). I've done alot of work in making sure everything is cached properly, caching pages in files so avoid sql queries and generally limiting the number of sql queries. Overall it looks like it's very speedy. The average time taken for the front page (taken over 100 times) is 0.046152 microseconds. But one thing i'm not sure about is whether i've done enough to reduce php memory usage. The only time i've ever encountered problems with it is when uploading large files. Using memory_get_peak_usage(TRUE), which I THINK returns the highest amount of memory used whilst the script has been running, the average (taken over 100 times) is 1572864 bytes. Is that good? I realise you don't know what it is i'm doing (it's rather simple, get the 10 latest articles, the comment count for each, get the user controls, popular tags in the sidebar etc). But would you be at all worried with a script using that sort of memory getting hit 50,000 times a day? Or once every second at peak times? I realise that this is a very open ended question. Hopefully you can understand that it's a bit of a stab in the dark and i'm really just looking for some re-assurance that it's not going to die horribly come re-launch day.

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  • Temporarily disable vim plugin without relaunching

    - by simont
    I'm using c-support in Vim. One of it's features is the automatic comment expansion. When I'm pasting code into Vim from an external editor, the comments are expanded (which gives me double-comments and messes up the paste - see below for example). I'd like to be able to disable the plugin, paste, then re-enable it, without relaunching Vim. I'm not sure if this is possible. The SO questions here, here and here all describe methods to disable plugins, but they all require me to close Vim, mess with my .vimrc or similar, and relaunch; if I have to close Vim, I might as well cat file1 >> myfile; vim myfile, then shift the lines internally, which will be just as quick. Is it possible to disable a plugin while running vim without relaunching, preferably in a way which allows me to map a hot-key toggle-plugin (so re-sourcing ~/.vimrc is alright; that's mappable to a hotkey [I imagine, haven't tried it yet])? Messed up comments: /* * * Authors: * * A Name * * * * Copyright: * * A Name, 2012 * */ EDIT: It turns out you can :set paste, :set nopaste (which, to quote :help paste, will "avoid unexpected effects [while pasting]". (See the comments). However, I'm still curious whether you can disable/enable a plugin as per the original question, so I shall leave the question open.

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  • Strategy for animation a lot of LED's - thread?, UIView animations? NSOperation? (iPhone)

    - by RickiG
    Hi I have to do some different views containing 72 LED lights. I built an LED Class so I can loop through the LED's and set them to different colors (Green, Red, Orange, Blue None etc.). The LED then loads the appropriate .png. This works fine, I loop over the LED's and set them. Now I know that at some time they will need to not just turn on/off change color, but will have to turn on with a small delay. Like an equalizer. I have a 5-10 views containing the 72 LED's and I would like to achieve the above with the minimum amount of memory/CPU strain. for(LED *l in self.ledArray) { [l display:Green]; } I simply loop as shown above and inside the LED is a switch case that does the correct logic. If this were actual LED's and a microController I would use sleep(100) or similar in the loop, but I would really like to avoid stuff like that for obvious reasons. I was thinking that doing a performOnThread withDelay would really be consuming, so would UIView animation changing the alpha and NSOperation would also be a lot of lifting for a small feature. Is there a both efficient and clever way to go around this? Thanks for any inspiration given:)

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  • Avoiding repetition with libraries that use a setup + execute model

    - by lijie
    Some libraries offer the ability to separate setup and execution, esp if the setup portion has undesirable characteristics such as unbounded latency. If the program needs to have this reflected in its structure, then it is natural to have: void setupXXX(...); // which calls the setup stuff void doXXX(...); // which calls the execute stuff The problem with this is that the structure of setupXXX and doXXX is going to be quite similar (at least textually -- control flow will prob be more complex in doXXX). Wondering if there are any ways to avoid this. Example: Let's say we're doing signal processing: filtering with a known kernel in the frequency domain. so, setupXXX and doXXX would probably be something like... void doFilter(FilterStuff *c) { for (int i = 0; i < c->N; ++i) { doFFT(c->x[i], c->fft_forward_setup, c->tmp); doMultiplyVector(c->tmp, c->filter); doFFT(c->tmp, c->fft_inverse_setup, c->x[i]); } } void setupFilter(FilterStuff *c) { setupFFT(..., &(c->fft_forward_setup)); // assign the kernel to c->filter ... setupFFT(..., &(c->fft_inverse_setup)); }

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  • How do I deal with different requests that map to the same response?

    - by daxim
    I'm designing a Web service. The request is idempotent, so I chose the GET method. The response is relatively expensive to calculate and not small, so I want to get caching (on the protocol level) right. (Don't worry about memoisation at my part, I have that already covered; my question here is actually also paying attention to the Web as a whole.) There's only one mandatory parameter and a number of optional parameter with default values if missing. For example, the following two map to the same representation of the response. (If this is a dumb way to go about it the interface, propose something better.) GET /service?mandatory_parameter=some_data HTTP/1.1 GET /service?mandatory_parameter=some_data;optional_parameter=default1;another_optional_parameter=default2;yet_another_optional_parameter=default3 HTTP/1.1 However, I imagine clients do not know this and would treat them separate and therefore waste cache storage. What should I do to avoid violating the golden rule of caching? Make up a canonical form, document it (e.g. all parameters are required after all and need to be sorted in a specific order) and return a client error unless the required form is met? Instead of an error, redirect permanently to the canonical form of a request? Or is it enough to not mind how the request looks like, and just respond with the same ETag for same responses?

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  • codeigniter avoiding html div's

    - by rabidmachine9
    Hello there!Is there a proper syntax to avoid div's in codeigniter? I don't really like opening and closing tags all the time... <div class="theForm"> <?php echo form_open('edit/links');//this form uploads echo "Enter the Name: ". form_input('name','name'); echo "Enter the Link: ". form_input('url','url'); echo " ".form_submit('submit', 'Submit'); echo form_close(); if (isset($linksQuery) && count($linksQuery)){ foreach($linksQuery as $link){ echo anchor($link['link'], $link['name'].".", array("class" => "links")); echo form_open('edit/links',array('class' => 'deleteForm')); echo form_hidden('name',$link['name']); echo " ".form_submit('delete','Delete'); echo form_close(); echo br(2); } } ?> </div>

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  • Regular Expressions, avoiding HTML tags in PHP

    - by Jason Axelrod
    I have actually seen this question quite a bit here, but none of them are exactly what I want... Lets say I have the following phrase: Line 1 - This is a TEST phrase. Line 2 - This is a <img src="TEST" /> image. Line 3 - This is a <a href="somelink/TEST">TEST</a> link. Okay, simple right? I am trying the following code: $linkPin = '#(\b)TEST(\b)(?![^<]*>)#i'; $linkRpl = '$1<a href="newurl">TEST</a>$2'; $html = preg_replace($linkPin, $linkRpl, $html); As you can see, it takes the word TEST, and replaces it with a link to test. The regular expression I am using right now works good to avoid replacing the TEST in line 2, it also avoids replacing the TEST in the href of line 3. However, it still replaces the text encapsulated within the tag on line 3 and I end up with: Line 1 - This is a <a href="newurl">TEST</a> phrase. Line 2 - This is a <img src="TEST" /> image. Line 3 - This is a <a href="somelink/TEST"><a href="newurl">TEST</a></a> link. This I do not want as it creates bad code in line 3. I want to not only ignore matches inside of a tag, but also encapsulated by them. (remember to keep note of the / in line 2)

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  • Recommendation for using equals in Entities and avoiding LazyInitializationExceptions?

    - by huxendupsel
    In the beginning there is a problem that wants to be solved. In my case i got an LazyInitializationException while using indexof in a Collection to retrieve an Object for manipulation. Here i start to think about using equals in EntityBeans (OR-Mapper at all). I know there are some discussions about overriding equals in association with OR-Mapper as hibernate like [1] Entities equals(), hashCode() and toString(). How to correctly implement them? [2] To equals and hashcode or not on entity classes, that is the question. [3] Overriding equals and hashCode in Java I currently have some entities which implements the equals but inside the code i could not use equals several times because of the LazyInitializationExceptions. So i had to workaround and use eg. the name property of the object to identify it's equality. From my point of view the whole 'LazyInitializationException-thing' is not really mentioned in this questions. I'd like to know have you got some good patterns or real live recommendations how to avoid such exception in an equal-Method. Shall i use some helper Methodes to distinguish if a Object of a class is already initialized (4) or should i apdicate the use of equals and use helper classes instead (2)? And what is about catching LazyInitializationExceptions in the equals? [Edit]: If you put equals in context with the initialization of the Object then it will gain importance. Sometimes it is nessesary to have the Object fully initialized but sometimes you don't want to. Because you just need the Object itself (name, id, ...) not its Collection-Properties. So just for equalization you have to reattach the Object and load the whole bunch you don't realy need? Are there any other solutions for such a problem?

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  • How to multi-thread this?

    - by WilliamKF
    I wish to have two threads. The first thread1 occasionally calls the following pseudo function: void waitForThread2() { if (thread2 is not idle) { return; } notifyThread2IamReady(); while (thread2IsExclusive) { } } The second thread2 is forever in the following pseudo loop: for (;;) { Notify thread1 I am idle. while (!thread1IsReady()) { } Notify thread1 I am exclusive. Do some work while thread1 is blocked. Notify thread1 I am busy. Do some work in parallel with thread1. } What is the best way to write this such that both thread1 and thread2 are kept as busy as possible on a machine with multiple cores. I would like to avoid long delays between notification in one thread and detection by the other. I tried using pthread condition variables but found the delay between thread2 doing 'notify thread1 I am busy' and the loop in waitForThread2() on thear2IsExclusive() can be up to almost one second delay. I then tried using a volatile sig_atomic_t shared variable to control the same, but something is going wrong, so I must not be doing it correctly.

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  • How to make a piece of WPF content take up the entire application window

    - by Bojin Li
    I'm working on an application that contains a number of content areas. I want to implement a behavior such that in response to user input, any of these content areas can be toggled to fit the entire application window, and optionally back to its original position again. I experimented with several approaches and none of them seem optimal for me. Here's what I tried to do: Use the ClipToBoundsProperty on the content I want to make "Full Screen": Doesn't work because only the CanvasPanel seems to fully respect this property. The application need to be localized so I would really like to avoid the CanvasPanel. Use a Grid and collapse the other content areas, such that only the one I want to see is visible, hence taking up the entire screen: This will probably work but doesn't seem easy to implement nor maintain. The "Full Screen" content area could be several levels deep, for example residing inside a Tabcontrol, so I would have to hide the tab headers too etc. Reconstruct the content area in a separate view and display it while hiding the rest: Seems easy enough to do with DataTemplates and my ViewModel objects, but any GUI/View only states are not preserved using this approach. Somehow "lift" the GUI/View I want to "Full Screen" into the separate view and display it while hiding the rest: I don't know how to do this or even if this is possible. Anyway if anyone knows a better approach I would love to know about it. Thanks a lot!

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  • TV Guide script - getting current date programmes to show

    - by whitstone86
    This is part of my TV guide script: //Connect to the database mysql_connect("localhost","root","PASSWORD"); //Select DB mysql_select_db("mytvguide"); //Select only results for today and future $result = mysql_query("SELECT programme, channel, episode, airdate, expiration, setreminder FROM mediumonair where airdate >= now()"); The episodes show up, so there are no issues there. However, it's getting the database to find data that's the issue. If I add a record for a programme that airs today this should show: Medium showing on TV4 8:30pm "Episode" Set Reminder Medium showing on TV4 May 18th - 6:25pm "Episode 2" Set Reminder Medium showing on TV4 May 18th - 10:25pm "Episode 3" Set Reminder Medium showing on TV4 May 19th - 7:30pm "Episode 3" Set Reminder Medium showing on TV4 May 20th - 1:25am "Episode 3" Set Reminder Medium showing on TV4 May 20th - 6:25pm "Episode 4" Set Reminder but this shows instead: Medium showing on TV4 May 18th - 6:25pm "Episode 2" Set Reminder Medium showing on TV4 May 18th - 10:25pm "Episode 3" Set Reminder Medium showing on TV4 May 19th - 7:30pm "Episode 3" Set Reminder Medium showing on TV4 May 20th - 1:25am "Episode 3" Set Reminder Medium showing on TV4 May 20th - 6:25pm "Episode 4" Set Reminder I almost have the SQL working; just not sure what the right code is here, to avoid the second mistake showing - as the record (which indicates a show currently airing) does not seem to work at present. Please can anyone help me with this? Thanks

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  • Java - multithreaded access to a local value store which is periodically cleared

    - by Telax
    I'm hoping for some advice or suggestions on how best to handle multi threaded access to a value store. My local value storage is designed to hold onto objects which are currently in use. If the object is not in use then it is removed from the store. A value is pumped into my store via thread1, its entry into the store is announced to listeners, and the value is stored. Values coming in on thread1 will either be totally new values or updates for existing values. A timer is used to periodically remove any value from the store which is not currently in use and so all that remains of this value is its ID held locally by an intermediary. Now, an active element on thread2 may wake up and try to access a set of values by passing a set of value IDs which it knows about. Some values will be stored already (great) and some may not (sadface). Those values which are not already stored will be retrieved from an external source. My main issue is that items which have not already been stored and are currently being queried for may arrive in on thread1 before the query is complete. I'd like to try and avoid locking access to the store whilst a query is being made as it may take some time.

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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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