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  • Return value of a JQuery autocomplete using an array of objects as its source

    - by user2920430
    In a JQuery autocomplete which uses an array of objects as its source, can I display the label in the INPUT and later access the value? The default behavior is that the value is displayed in the INPUT after selection. In this case the values represent indexes to unique keys in rows in a table. <!doctype html> <html lang="en"> <head> <meta charset="utf-8"> <title>autocomplete demo</title> <link rel="stylesheet" href="http://code.jquery.com/ui/1.10.3/themes/smoothness/jquery-ui.css"> <script src="http://code.jquery.com/jquery-1.9.1.js"></script> <script src="http://code.jquery.com/ui/1.10.3/jquery-ui.js"></script> </head> <body> <label for="autocomplete">Select a programming language: </label> <input id="autocomplete"> <script> $( "#autocomplete" ).autocomplete({ source: [ { label:"c++", value:1 }, { label: "java", value:2 }, { label: "javascript", value:3 } ] }); </script> </body> </html>

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  • NSManagedObject How To Reload

    - by crissag
    I have a view that consists of a table of existing objects and an Add button, which allows the user to create a new object. When the user presses Add, the object is created in the list view controller, so that the object will be part of that managed object context (via the NSEntityDescription insertNewObjectForEntityForName: method). The Add view has a property for the managed object. In the list view controller, I create an Add view controller, set the property to the managed object I created, and then push the Add view on to the navigation stack. In the Add view, I have two buttons for save and cancel. In the save, I save the managed object and pass the managed object back to the list view controller via a delegate method. If the user cancels, then I delete the object and pass nil back to the list view controller. The complication I am having in the add view is related to a UIImagePickerController. In the Add view, I have a button which allows the user to take a photo of the object (or use an existing photo from the photo library). However, the process of transferring to the UIImagePickerController and having the user use the camera, is resulting in a didReceiveMemoryWarning in the add view controller. Further, the view was unloaded, which also caused my NSManagedObject to get clobbered. My question is, how to you go about reloading the NSManagedObject in the case where it was released because of the low memory situation?

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  • Prevent empty form input array from being posted?

    - by user355295
    Sorry if this has been answered somewhere; I'm not quite sure how to phrase the problem to even look for help. Anyway, I have a form with three text input boxes, where the user will input three song titles. I have simple PHP set up to treat those input boxes as an array (because I may want, say, 100 song titles in the future) and write the song titles to another document. <form method="post"> <input type="text" name="songs[]" value="" /> <input type="text" name="songs[]" value="" /> <input type="text" name="songs[]" value="" /> <button type="submit" name="submit" value="submit">Submit</button> </form> <?php if (isset($_POST['submit'])) { $open = fopen("test.html", "w"); if(empty($_POST['songs'])) { } else { $songs = $_POST['songs']; foreach($songs as $song) { fwrite($open, $song."<br />"); }; }; }; ?> This correctly writes the song titles to an external file. However, even when the input boxes are empty, the external file will still be written to (just with the <br />'s). I'd assumed that the if statement would ensure nothing would happen if the boxes were blank, but that's obviously not the case. I guess the array's not really empty like I thought it was, but I'm not really sure what implications that comes with. Any idea what I'm doing wrong? (And again, I am clueless when it comes to PHP, so forgive me if this has been answered a million times before, if I described it horribly, etc.)

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  • SQL aggregate query question

    - by Phil
    Hi, Can anyone help me with a SQL query in Apache Derby SQL to get a "simple" count. Given a table ABC that looks like this... id a b c 1 1 1 1 2 1 1 2 3 2 1 3 4 2 1 1 ** 5 2 1 2 ** ** 6 2 2 1 ** 7 3 1 2 8 3 1 3 9 3 1 1 How can I write a query to get a count of how may distinct values of 'a' have both (b=1 and c=2) AND (b=2 and c=1) to get the correct result of 1. (the two rows marked match the criteria and both have a value of a=2, there is only 1 distinct value of a in this table that match the criteria) The tricky bit is that (b=1 and c=2) AND (b=2 and c=1) are obviously mutually exclusive when applied to a single row. .. so how do I apply that expression across multiple rows of distinct values for a? These queries are wrong but to illustrate what I'm trying to do... "SELECT DISTINCT COUNT(a) WHERE b=1 AND c=2 AND b=2 AND c=1 ..." .. (0) no go as mutually exclusive "SELECT DISTINCT COUNT(a) WHERE b=1 AND c=2 OR b=2 AND c=1 ..." .. (3) gets me the wrong result. SELECT COUNT(a) (CASE WHEN b=1 AND c=10 THEN 1 END) FROM ABC WHERE b=2 AND c=1 .. (0) no go as mutually exclusive Cheers, Phil.

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  • Retrieving friend's likes from the Facebook Graph API

    - by Joe Frank
    Howdy- I have been tooling around with the Facebook Graph API and successfully retrieved back a list of my likes, and a list of my friends (once I authenticated using OAuth). But what I really want to achieve is pulling back my friend's likes. When I try and do that, obviously using the same URL that I use to pull back my own likes but subbing the friend's user id for "me", I don't get anything back, unless they have installed the app as well. Then I get them no problem. To be clear, I can only see the likes of friends who have installed my application. So clearly I am running into a security/rights issue of some sort. I could see where this would be the case; you simply aren't allowed to see your friend's likes unless they have installed the same app. Fair enough, but then how is blekko.com doing it? I even tried using FQL without much luck. I suspect I am missing something totally obvious. Anyone had any luck with this? Maybe with the Javascript API or one of the other access methods? Thanks in advance for any guidance.

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  • What's the deal with the hidden Throw when catching a ThreadAbortException?

    - by priehl
    I'm going through a book of general c# development, and I've come to the thread abort section. The book says something along the lines that when you call Thread.Abort() on another thread, that thread will throw a ThreadAbortException, and even if you tried to supress it it would automatically rethrow it, unless you did some bs that's generally frowned upon. Here's the simple example offered. using System; using System.Threading; public class EntryPoint { private static void ThreadFunc() { ulong counter = 0; while (true) { try { Console.WriteLine("{0}", counter++); } catch (ThreadAbortException) { // Attempt to swallow the exception and continue. Console.WriteLine("Abort!"); } } } static void Main() { try { Thread newThread = new Thread(new ThreadStart(EntryPoint.ThreadFunc)); newThread.Start(); Thread.Sleep(2000); // Abort the thread. newThread.Abort(); // Wait for thread to finish. newThread.Join(); } catch (Exception e) { Console.WriteLine(e.ToString()); } } } The book says: When your thread finishes processing the abort exception, the runtime implicitly rethrows it at the end of your exception handler. It’s the same as if you had rethrown the exception yourself. Therefore, any outer exception handlers or finally blocks will still execute normally. In the example, the call to Join won’t be waiting forever as initially expected. So i wrapped a try catch around the Thread.Abort() call and set a break point, expecting it to hit this, considering the text says "any outer exception handlers or finally blocks will still execute normally". BUT IT DOES NOT. I'm racking my brain to figure out why. Anyone have any thoughts on why this isn't the case? Is the book wrong? Thanks in advance.

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  • Selenium : Handling Loading screens obscuring the web elements. (Java)

    - by Sheldon Cooper
    I'm writing an automated test case for a web page. Here's my scenario. I have to click and type on various web elements in an html form. But, sometimes while typing on a text field, an ajax loading image appears , fogging all elements i want to interact with. So, I'm using web-driver wait before clicking on the actual elements like below, WebdriverWait innerwait=new WebDriverWait(driver,30); innerwait.until(ExpectedConditions.elementToBeClickable(By.xpath(fieldID))); driver.findelement(By.xpath(fieldID)).click(); But the wait function returns the element even if it is fogged by another image and is not clickable. But the click() throws an exception as Element is not clickable at point (586.5, 278). Other element would receive the click: <div>Loading image</div> Do I have to check every time if the loading image appeared before interacting with any elements?.(I can't predict when the loading image will appear and fog all elements.) Is there any efficient way to handle this? Currently I'm using the following function to wait till the loading image disappears, public void wait_for_ajax_loading() throws Exception { try{ Thread.sleep(2000); if(selenium.isElementPresent("id=loadingPanel")) while(selenium.isElementPresent("id=loadingPanel")&&selenium.isVisible("id=loadingPanel"))//wait till the loading screen disappears { Thread.sleep(2000); System.out.println("Loading...."); }} catch(Exception e){ Logger.logPrint("Exception in wait_for_ajax_loading() "+e); Logger.failedReport(report, e); driver.quit(); System.exit(0); } } But I don't know exactly when to call the above function, calling it at a wrong time will fail. Is there any efficient way to check if an element is actually clickable? or the loading image is present? Thanks..

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  • Very Urgent :How to start a new session if a user click on the new tab in IE or mozilla on websphere

    - by ha22109
    Hi, I have one "user search" portlet on the home page of one application running on websphere portal server.Which display the matching user records as per the search criteria filled in the search form.I have requirement to have a "back to search input" link on the results page which onclick should show the filled form on the input jsp. The issue which i am facing is if i open the application in two diff tab of same IE browser and start giving some search criteria and submit and same time search for some other input from other IE tab (in the same browser)and then go back to previous tab and click on "back to search input" link then instead of showing me the first input it will show me the imput which i entered in the next IE tab. I am setting and getting the bean(form bean) through portlet session.but in the two diff tab of same IE it will be the sae user session (and may be the same portlet session..) Please tell me solution for this. The one thing to be notice here is i can access this "user search" application even without doing login also.so it must be taking the default portlet session in this case. what wil happen once i login and then search,will it going to overwrite the portlet session and http session or howz is that?

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  • C Population Count of unsigned 64-bit integer with a maximum value of 15

    - by BitTwiddler1011
    I use a population count (hamming weight) function intensively in a windows c application and have to optimize it as much as possible in order to boost performance. More than half the cases where I use the function I only need to know the value to a maximum of 15. The software will run on a wide range of processors, both old and new. I already make use of the POPCNT instruction when Intel's SSE4.2 or AMD's SSE4a is present, but would like to optimize the software implementation (used as a fall back if no SSE4 is present) as much as possible. Currently I have the following software implementation of the function: inline int population_count64(unsigned __int64 w) { w -= (w 1) & 0x5555555555555555ULL; w = (w & 0x3333333333333333ULL) + ((w 2) & 0x3333333333333333ULL); w = (w + (w 4)) & 0x0f0f0f0f0f0f0f0fULL; return int(w * 0x0101010101010101ULL) 56; } So to summarize: (1) I would like to know if it is possible to optimize this for the case when I only want to know the value to a maximum of 15. (2) Is there a faster software implementation (for both Intel and AMD CPU's) than the function above?

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  • Entities used to serialize data have changed. How can the serialized data be upgraded for the new entities?

    - by i8abug
    Hi, I have a bunch of simple entity instances that I have serialized to a file. In the future, I know that the structure of these entities (ie, maybe I will rename Name to Header or something). The thing is, I don't want to lose the data that I have saved in all these old files. What is the proper way to either load the data from the old entities into new entities upgrade the old files so that they can be used with new entities Note: I think I am stuck with binary serialization, not xml serialization. Thanks in advance! Edit: So I have an answer for the case I have described. I can use a dataContractSerializer and do something like [DataMember("bar")] private string foo; and change the name in the code and keep the same name that was used for serialization. But what about the following additional cases: The original entity has new members which can be serialized Some serialized members that were in the original entity are removed Some members have actually changed in function (suppose that the original class had a FirstName and LastName member and it has been refactored to have only a FullName member which combines the two) To handle these, I need some sort of interpreter/translator deserialization class but I have no idea what I should use

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  • Stop SQL returning the same result twice in a JOIN

    - by nbs189
    I have joined together several tables to get data i want but since I am new to SQL i can't figure out how to stop data being returned more than once. her's the SQL statement; SELECT T.url, T.ID, S.status, S.ID, E.action, E.ID, E.timestamp FROM tracks T, status S, events E WHERE S.ID AND T.ID = E.ID ORDER BY E.timestamp DESC The data that is returned is something like this; +----------------------------------------------------------------+ | URL | ID | Status | ID | action | ID | timestamp | +----------------------------------------------------------------+ | T.1 | 4 | hello | 4 | has uploaded a track | 4 | time | | T.2 | 3 | bye | 3 | has some news | 3 | time | | t.1 | 4 | more | 4 | has some news | 4 | time | +----------------------------------------------------------------+ That's a very basic example but does outline what happens. If you look at the third row the URL is repeated when there is a different status. This is what I want to happen; +-------------------------------------------------------+ | URL or Status | ID | action | timestamp | +-------------------------------------------------------+ | T.1 | 4 | has uploaded a track | time | | hello | 3 | has some news | time | | bye | 4 | has some news | time | +-------------------------------------------------------+ Please notice that the the url (in this case the mock one is T.1) is shown when the action is has uploaded a track. This is very important. The action in the events table is inserted on trigger of a status or track insert. If a new track is inserted the action is 'has uploaded a track' and you guess what it is for a status. The ID and timestamp is also inserted into the events table at this point. Note: There are more tables that go into the query, 3 more in fact, but I have left them out for simplicity.

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  • Is there a maximum number of input controls that can be used on an HTML form?

    - by Rich
    I have an ambitious requirement for an asp.net 2.0 web page that contains a table (gridview), and each row in the grid contains 6 select (dropdown) controls for data entry. The number of rows that will be displayed is dependent upon the user's search parameters, which are specified in another area of the page. Unfortunately, with the default (and even basic) search parameters specified, the grid could contain several hundred rows. I've noticed that the browser, in this case IE8, starts behaving rather erratically once I reach a large number of rows -- no documented evidence for the number of rows where this begins to be a problem. For example, trying to view the source of the page results in a message from IE stating that there was a problem with the page that forced the browser to reload it, and I never get the source. Obviously the page loads and renders rather slowly also. I know that my solution is probably going to involve paging the gridview such that it only displays 20 or so rows per page, and I'll have to write code to handle the saving of changes in the dropdown values when the user changes pages. I can probably turn off viewstate on the gridview also. However, the question I really want to pose is this -- has anyone seen a documented rule indicating the maximum number of input controls that an HTML browser form is supposed to be able to contain? I could not find anything on the Internet after doing a search, and I suspect the answer may be whatever the browser can handle based on the machine configuration it is running on. Any rules of thumb you use? Thanks for any suggestions. Rich

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  • Best way to do one-to-many "JOIN" in CouchDB

    - by mit
    There are CouchDB documents that are list elements: { "type" : "el", "id" : "1", "content" : "first" } { "type" : "el", "id" : "2", "content" : "second" } { "type" : "el", "id" : "3", "content" : "third" } There is one document that defines the list: { "type" : "list", "elements" : ["2","1"] , "id" : "abc123" } As you can see the third element was deleted, it is no longer part of the list. So it must not be part of the result. Now I want a view that returns the content elements including the right order. The result could be: { "content" : ["second", "first"] } In this case the order of the elements is already as it should be. Another possible result: { "content" : [{"content" : "first", "order" : 2},{"content" : "second", "order" : 1}] } I started writing the map function: map = function (doc) { if (doc.type === 'el') { emit(doc.id, {"content" : doc.content}); //emit the id and the content exit; } if (doc.type === 'list') { for ( var i=0, l=doc.elements.length; i<l; ++i ){ emit(doc.elements[i], { "order" : i }); //emit the id and the order } } } This is as far as I can get. Can you correct my mistakes and write a reduce function? Remember that the third document must not be part of the result. Of course you can write a different map function also. But the structure of the documents (one definig element document and an entry document for each entry) cannot be changed.

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  • I have a slight confusion with setting up Mercurial on my webserver...

    - by littlejim84
    I'm starting to use Mercurial on my web server (in this case MediaTemple's Grid). I've used SVN previously, though I'm not an expert of version control systems. I'm just needing a little help with clearing up some confusion with getting it set up optimally. I have a 'data' folder which is outside the web server root and that the browser cannot access. It was recommended to me before to have my Mercurial repositories setup here, then I would clone from here locally on my computer. I would also have a 'domains' folder that is basically the web server root and inside there is my actual domains where my websites are actually served to the browser - these would need to be updated from the 'data' repositories too. But with this in mind, after setting it up, it seems inefficient... I'm cloning to my local (that makes sense), adding, committing, pushing. That's fine... But then I'm then updating in my data repository folder and then updating in my domains folder to actually update my websites. Surely, I don't actually need this 'data' folder for repositories? Wouldn't my actual live 'domains' folders be the main repositories themselves? So I'm cloning locally and updating from these? Please help me clear some confusions with all this (if you can).

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  • Python - Access a class from a list using a key

    - by Fake Name
    Is there any way to make a list of classes behave like a set in python? Basically, I'm working on a piece of software that does some involved string comparison, and I have a custom class for handling the strings. Therefore, there is an instance of the class for each string. As a result, I have a large list containing all these classes. I would like to be able to access them like list[key], where in this case, the key is a string the class is based off of. It seems to me that I sould be able to do this somewhat easily, by adding something like __cmp__ to the class, but either I'm being obtuse (likely), or Im missing someting in the docs. Basically, I want to be able to do something like this (Python prompt example): >>class a: ... def __init__(self, x): ... self.var = x ... >>> from test import a >>> cl = set([a("Hello"), a("World"), a("Pie")]) >>> print cl set([<test.a instance at 0x00C866C0>, <test.a instance at 0x00C866E8>, <test.a instance at 0x00C86710>]) >>> cl["World"] <test.a instance at 0x00C866E8> Thanks!

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  • Canvas - @font-face doesn't work on IE9+

    - by iMoses
    I've created a widget which allows the user to locate free-text over an image using a textarea. When saving the image a background canvas application reads the text and calculates its position, then it draws the text to the canvas over the image and saves a new image file. The font I use for this widget is league-gothic which I am importing using the @font-face method. This seems to work great and without any issues on all browsers except (of-course) for IE9 and IE10. When using internet explorer you can clearly see that the font was indeed loaded since the textarea uses the same font, but when trying to draw the text onto the canvas the font-family reverts to one of its fallback, in this case Arial. I've searched quite a bit and found nothing. Unlike most font issues I found that concern the canvas element, I am completely sure that the font has indeed loaded as I am viewing it before saving the result. Anything at all will help me at the moment. If you have any insight, experience with similar bugs or whatever, please share :) Thanks in advance. P.S. I can't expose a code example at the moment, but if it becomes a problem I'll do my best to provide one.

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  • MS 70-536 .NET Framework Foundation - info on Exam? Especially regex?

    - by Sebastian P.R. Gingter
    Hi, I know there are already some questions about this, but not that specific. I have the self-paced training kit and worked through the test exam tool that is on the CD coming with the book. I constantly fail on the test tool, mostly on the regex questions. I'm not a regex guru. In fact my regex-fu is more than weak. I know what regex'es are, how I can use them and where my 'Regular expressions - kurz und gut' book is in my drawer in case I really need them. And to be honest I feel like learning regex is a total waste of time, because if I need them I have either a colleague that is fit and can do them in just a few seconds or I need my book and get them right in a still fair amount of time. And from my experience I can tell that I need regex like once in two or three years. So just putting in a lot of time into learning just the expressions to pass the exam is.. something I like not to have to do. Can you tell me something about the real exam vs. the test exam tool on the book and about the need to know regex for passing it? Thank you for your time. Marked as Community Wiki. Hope that fits?

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  • How to insert result of mysql_real_escape_string() into oracle database?

    - by Prat
    For inserting special characters in data like (,')etc., I am using musql_real_escape_string() function & it's working fine. Now I want to use same variable while inserting values in Oracle. $str = 'N.G.Palace\'s Building', 'xyzcity', '12345678','India','100001',12 Here $str is result of mysql_real_escape_string(). so it escapes special character. Now my code for oracle is like this-: $qry ="INSERT INTO Ora_table(ship_to_street, ship_to_city,ship_to_country, ship_to_telephone, order_id, record_no) VALUES(".$str); So my doubt is Oracle is not accepting values return by mysql_real_escape_string i.e. Palace\'s (like this as this mysql function attach \ before 'single quote)? So can anybody tell me ho9w can I use that variable $str to insert data into Oracle? Also I tried like this also-: "q"."'"."c".$str."c"."'" can we use this for multiple values like in my case...though still I am unable to inser data in oracle? plz help.

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  • Difference dynami static 2d array c++

    - by snorlaks
    Hello, Im using opensource library called wxFreeChart to draw some XY charts. In example there is code which uses static array as a serie : double data1[][2] = { { 10, 20, }, { 13, 16, }, { 7, 30, }, { 15, 34, }, { 25, 4, }, }; dataset-AddSerie((double *) data1, WXSIZEOF(dynamicArray)); WXSIZEOF ismacro defined like: sizeof(array)/sizeof(array[0]) In this case everything works great but in my program Im using dynamic arrays (according to users input). I made a test and wrotecode like below: double **dynamicArray = NULL; dynamicArray = new double *[5] ; for( int i = 0 ; i < 5 ; i++ ) dynamicArray[i] = new double[2]; dynamicArray [0][0] = 10; dynamicArray [0][1] = 20; dynamicArray [1][0] = 13; dynamicArray [1][1] = 16; dynamicArray [2][0] = 7; dynamicArray [2][1] = 30; dynamicArray [3][0] = 15; dynamicArray [3][1] = 34; dynamicArray [4][0] = 25; dynamicArray [4][1] = 4; dataset-AddSerie((double *) *dynamicArray, WXSIZEOF(dynamicArray)); But it doesnt work correctly. I mean point arent drawn. I wonder if there is any possibility that I can "cheat" that method and give it dynamic array in way it understands it and will read data from correct place thanks for help

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  • Pointer mysteriously moves

    - by Armen Ablak
    Hi, I have this code for Node rotation and in a line which is marked something happens and I don't really know what and why :). //Test case 30 \ 16 / 29 RotationRight(node->mParent); //call template<class T> void SplayTree<T>::RotationRight(SplayNode<T> *&node) const { SplayNode<T> *left = node->mLeft; SplayNode<T> *parent = node->mParent; node->mLeft = left->mRight; if(left->HasRight()) left->mRight->mParent = node; left->mRight = node; //node in this line points to 0x00445198 {30} left->mParent = node->mParent; //and in this line it points to 0x00444fb8 {16} (node, not node->mParent) node->mParent = left; node = left; } Well, left-mParent points to node also, so I basically do node = node-mParent. The problem is I can't find a work around - how to unpin in from node and change it's pointing address without changing it's.

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  • Making IE "forget" information entered in form when using back button.

    - by typoknig
    I have a page with a form where many of the fields are populated from variables passed in the URL. Those fields are disabled (NON-EDITABLE) and are only there for the user to view. The remaining fields require user input and are NOT disabled (EDITABLE). When the form is submitted a confirmation page comes up. It may be the case that the user needs to submit several of these forms where the NON-EDITABLE information is identical from form to form, so being able to go back to the form page from the confirmation page would save a lot of time. The way I want this to work is when a user presses the back button all the NON-EDITABLE fields are populated, but the EDITABLE fields are blank. This is what Firefox is doing, but IE8 is does not "forget" what has been entered in the EDITABLE fields. To disable the cache the following appears at the beginning of my page AND at the end of my page. <head> <meta http-equiv="Pragma" content="no-cache"/> <meta http-equiv="Cache-Control" content="no-store"/> <head/> What more must I do to make IE forget what was entered in the EDITABLE fields when the back button is pressed? All of my pages are generated with PHP if that matters. EDIT: It appears to me that this is a problem of IE caching my page even though I have told it not to. Are my meta tags correct? Do I need to do something else to prevent IE from caching my page?

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  • What am I doing wrong with SVN merging?

    - by randomusername
    When SVN with merge tracking works, it's really nice, I love it. But it keeps getting twisted up. We are using TortoiseSVN. We continuously get the following message: Error: Reintegrate can only be used if revisions 1234 through 2345 were previously merged from /Trunk to the reintegrate source, but this is not the case For reference, this is the method we are using: Create a Branch Develop in the branch Occasionally Merge a range of revisions from the Trunk to the Branch When branch is stable, Reintegrate a branch from the branch to the trunk Delete the branch I Merge a range of revisions from the trunk to the branch (leaving the range blank, so it should be all revisions) just prior to the reintegrate operation, so the branch should be properly synced with the trunk. Right now, the Trunk has multiple SVN merge tracking properties associated with it. Should it? Or should a Reintegrate not add any merge tracking info? Is there something wrong with our process? This is making SVN unusable - 1 out of every 3 reintegrates forces me to dive in and hack at the merge tracking info.

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  • Does the Java Memory Model (JSR-133) imply that entering a monitor flushes the CPU data cache(s)?

    - by Durandal
    There is something that bugs me with the Java memory model (if i even understand everything correctly). If there are two threads A and B, there are no guarantees that B will ever see a value written by A, unless both A and B synchronize on the same monitor. For any system architecture that guarantees cache coherency between threads, there is no problem. But if the architecture does not support cache coherency in hardware, this essentially means that whenever a thread enters a monitor, all memory changes made before must be commited to main memory, and the cache must be invalidated. And it needs to be the entire data cache, not just a few lines, since the monitor has no information which variables in memory it guards. But that would surely impact performance of any application that needs to synchronize frequently (especially things like job queues with short running jobs). So can Java work reasonably well on architectures without hardware cache-coherency? If not, why doesn't the memory model make stronger guarantees about visibility? Wouldn't it be more efficient if the language would require information what is guarded by a monitor? As i see it the memory model gives us the worst of both worlds, the absolute need to synchronize, even if cache coherency is guaranteed in hardware, and on the other hand bad performance on incoherent architectures (full cache flushes). So shouldn't it be more strict (require information what is guarded by a monitor) or more lose and restrict potential platforms to cache-coherent architectures? As it is now, it doesn't make too much sense to me. Can somebody clear up why this specific memory model was choosen? EDIT: My use of strict and lose was a bad choice in retrospect. I used "strict" for the case where less guarantees are made and "lose" for the opposite. To avoid confusion, its probably better to speak in terms of stronger or weaker guarantees.

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  • Regex to GENERATE thumbnails!?!?! (but that's crazy!)

    - by CryptoMonkey
    Hello everyone! So here is my situation, and the solution that I've come up with to solve the problem. I have created an application that includes TinyMCE to allow users to create HTML content for publishing. The user can include images in their markup, and drag/resize those images effecting the final Width/Height attributes in the IMG tag. This is all great, the users can include images and resize/relocate them to their desired appearance. But one big problem is that I am now sending a (possibly) much larger image to the client, only to have the browser resize the image into the requested Width/Height attributes. All that bandwidth and lost load time.... So my solution is to pre-process my users markup content, scanning all of the IMG tags and parsing out the Height/Width/Src attributes. Then set each img's SRC tag to a phpThumb request with the parsed Height/Width passed into the thumbnails URL. This will create my reduced size image (optimising bandwidth at the expense of CPU and caching). What do you think about this solution? I've seen other posts where people were using mod_rewrite to do something similar, but I want to effect the content on the page service and not manipulate the image requests as they're being received. .... Any thoughts about this design? I need some help with the fine details as my regex skills need some work, but I'm very short on time and promise to pay my technical knowledge debt soon. To make the regex's easier, I can be sure of some things. Only img tags that need this processing will have an existing width="" height="" attributes (with the double quotes, and lower cased text, but I suppose matching the text case insensitive would be better if TinyMCE changes) So a regex to match only the necessary Img tags, and maybe another three regex's to extract the src, the width, and the height? Thanks everyone.

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  • Better way to catch trouble points

    - by mac
    User submits a CSV file which is consumed by a program. Values which are used throughout the program come from the CSV, natually if values are missed it is a problem. Below is my solution. Ip on top private List<String> currentFieldName = new ArrayList<String>(); As part of the method: try { setCurrentFieldName("Trim Space"); p.setTrimSpace(currentLineArray[dc.getTRIM_POSITION()].equals("yes") ? true : false); setCurrentFieldName("Ignore Case"); p.setIgnoreCase(currentLineArray[dc.getIGNORE_CASE_POSITION()].equals("yes") ? true : false); } catch (NullPointerException e) { throw new InputSpreadsheetValueUnassignedException("\"Type\" field not set: " + currentFieldName); } And the method which keeps track of a current field being looked at: private void setCurrentFieldName(String fieldName) { currentFieldName.clear(); currentFieldName.add(fieldName); } The idea there is that if user fails to submit value and i will end up getting null, before throwing an exception, i will know what value was not assigned. So, this being said, specific questions: Is what i have shown below an acceptable solution? Can you suggest something more elegant?

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