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• Share java object between two forms using Spring IoC

  - by Vladimir

  I want to share java object between two forms using Spring IoC. It should acts like Registry: Registry.set("key", new Object()); // ... Object o = Registry.get("key"); // ... Registry.set("key", new AnotherObject()); // rewrite old object I tried this code to register bean at runtime: applicationContext.getBeanFactory().registerSingleton("key", object); but it does not allow to rewrite existing object (result code for checking and deleting existing bean is too complicated)... PS I am Java newbie, so mb I am doing it wrong and I should not use IoC at all... any help is appreciated...

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• Distance between numpy arrays, columnwise

  - by Jaapsneep

  I have 2 arrays in 2D, where the column vectors are feature vectors. One array is of size F x A, the other of F x B, where A << B. As an example, for A = 2 and F = 3 (B can be anything): arr1 = np.array( [[1, 4], [2, 5], [3, 6]] ) arr2 = np.array( [[1, 4, 7, 10, ..], [2, 5, 8, 11, ..], [3, 6, 9, 12, ..]] ) I want to calculate the distance between arr1 and a fragment of arr2 that is of equal size (in this case, 3x2), for each possible fragment of arr2. The column vectors are independent of each other, so I believe I should calculate the distance between each column vector in arr1 and a collection of column vectors ranging from i to i + A from arr2 and take the sum of these distances (not sure though). Does numpy offer an efficient way of doing this, or will I have to take slices from the second array and, using another loop, calculate the distance between each column vector in arr1 and the corresponding column vector in the slice?

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• Make dictionary from list with python

  - by prosseek

  I need to transform a list into dictionary as follows. The odd elements has the key, and even number elements has the value. x = (1,'a',2,'b',3,'c') - {1: 'a', 2: 'b', 3: 'c'} def set(self, val_): i = 0 for val in val_: if i == 0: i = 1 key = val else: i = 0 self.dict[key] = val My solution seems to long, is there a better way to get the same results?

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• Basic Custom String Class for C++

  - by wdow88

  Hey all, I'm working on building my own string class with very basic functionality. I am having difficulty understand what is going on with the basic class that I have define, and believe there is some sort of error dealing with the scope occurring. When I try to view the objects I created, all the fields are described as (obviously bad pointer). Also, if I make the data fields public or build an accessor method, the program crashes. For some reason the pointer for the object is 0xccccccccc which points to no where. How can a I fix this? Any help/comments are much appreciated. //This is a custom string class, so far the only functions are //constructing and appending #include<iostream> using namespace std; class MyString1 { public: MyString1() { //no arg constructor char *string; string = new char[0]; string[0] ='\0'; std::cout << string; size = 1; } //constructor receives pointer to character array MyString1(char* chars) { int index = 0; //Determine the length of the array while (chars[index] != NULL) index++; //Allocate dynamic memory on the heap char *string; string = new char[index+1]; //Copy the contents of the array pointed by chars into string, the char array of the object for (int ii = 0; ii < index; ii++) string[ii] = chars[ii]; string[index+1] = '\0'; size = index+1; } MyString1 append(MyString1 s) { //determine new size of the appended array and allocate memory int newsize = s.size + size; MyString1 MyString2; char *newstring; newstring = new char[newsize+1]; int index = 0; //load the first string into the array while (string[index] != NULL) { newstring[index] = string[index]; index++; } //load the second string while (s.string[index] != NULL) { newstring[index] = s.string[index]; index++; } //null terminate newstring[newsize+1] = '\0'; delete string; //generate the object for return MyString2.string=newstring; MyString2.size=newsize; return MyString2; } private: char *string; int size; }; int main() { MyString1 string1; MyString1 string2("Hello There"); MyString1 string3("Buddy"); string2.append(string3); return 0; }

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• List of Big-O for PHP functions?

  - by Kendall Hopkins

  After using PHP for a while now, I've noticed that not all PHP built in functions as fast as expected. Consider the below two possible implementations of a function that finds if a number is prime using a cached array of primes. //very slow for large $prime_array $prime_array = array( 2, 3, 5, 7, 11, 13, .... 104729, ... ); $result_array = array(); foreach( $array_of_number => $number ) { $result_array[$number] = in_array( $number, $large_prime_array ); } //still decent performance for large $prime_array $prime_array => array( 2 => NULL, 3 => NULL, 5 => NULL, 7 => NULL, 11 => NULL, 13 => NULL, .... 104729 => NULL, ... ); foreach( $array_of_number => $number ) { $result_array[$number] = array_key_exists( $number, $large_prime_array ); } This is because in_array is implemented with a linear search O(n) which will linearly slow down as $prime_array grows. Where the array_key_exists function is implemented with a hash lookup O(1) which will not slow down unless the hash table gets extremely populated (in which case it's only O(logn)). So far I've had to discover the big-O's via trial and error, and occasionally looking at the source code. Now for the question... I was wondering if there was a list of the theoretical (or practical) big O times for all* the PHP built in functions. *or at least the interesting ones For example find it very hard to predict what the big O of functions listed because the possible implementation depends on unknown core data structures of PHP: array_merge, array_merge_recursive, array_reverse, array_intersect, array_combine, str_replace (with array inputs), etc.

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• Does my Dictionary must use locking mechanism?

  - by theateist

  Many threads have access to summary. Each thread will have an unique key for accessing the dictionary; Dictionary<string, List<Result>> summary; Do I need locking for following operations? summary[key] = new List<Result>() summary[key].Add(new Result()); It seems that I don't need locking because each thread will access dictionary with different key, but won't the (1) be problematic because of adding concurrently new record to dictionary with other treads?

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• Hibernate doesn't generate cascade

  - by Shervin

  Hi. I have a set hibernate.hbm2ddl.auto to create so that Hibernate creates the tables in mysql for me. However, it doesn't seem that hibernate correctly adds Cascade on the references in the table. It does however work when I for instance delete a row, and I have a delete cascade as hibernate annotation. So I guess that means that Hibernate reads the annoation on runtime, and perform cascading manually? Is that normal behavior? For instance: @Entity class Report { @OneToOne(cascade = CascadeType.ALL) public File getPdf() { return pdf; } } Here I have set cascade to ALL. However, when running show create table Report Report | CREATE TABLE `Report` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `pdf_id` bigint(20) DEFAULT NULL, PRIMARY KEY (`id`), KEY `FK91B14154FDE6543A` (`pdf_id`), CONSTRAINT `FK91B14154FDE6543A` FOREIGN KEY (`pdf_id`) REFERENCES `File` (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 | It doesn't say anything about cascading other then the foreign key. In my opinion, it should have added the ON DELETE CASCADE ON DELETE UPDATE

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• Ways to update a dependent table in the same MySQL transaction?

  - by codie

  I need to update two tables inside a single transaction. The individual queries look something like this: 1. INSERT INTO t1 (col1, col2) VALUES (val1, val2) ON DUPLICATE KEY UPDATE col2 = val2; If the above query causes an insert then I need to run the following statement on the second table: 2. INSERT INTO t2 (col1, col2) VALUES (val1, val2) ON DUPLICATE KEY UPDATE col2 = col2 + val2; otherwise, 3. UPDATE t2 SET col2 = col2 - old_val2 + val2 WHERE col1 = val1; -- old_val2 is the value of t1.col2 before it was updated Right now I run a SELECT on t1 first, to determine whether statement 1 will cause an insert or update on t1. Then I run statement 1 and either of 2 and 3 inside a transaction. What are the ways in which I can do all of these inside one transaction itself? The approach I was thinking of is the following: UPDATE t2, t1 set t2.col2 = t2.col2 - t1.col2 WHERE t1.col1 = t2.col2 and t1.col1 = val1; INSERT INTO t1 (col1, col2) VALUES (val1, val2) ON DUPLICATE KEY UPDATE col2 = val2; INSERT INTO t2, t1 (t2.col1, t2.col2) VALUES (t1.col1, t1.col2) ON DUPLICATE KEY UPDATE t2.col2 = t2.col2 + t1.col2 WHERE t1.col1 = t2.col2 and t1.col1 = val1; Unfortunately, there's no multi-table INSERT... ON DUPLICATE KEY UPDATE in MySQL 5.0. What else could I do?

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• VB.NET: Dialog exits when enter pressed?

  - by Camilo Martin

  Hi all; My problem seems to be quite simple, but it's not working the intuitive way. I'm designing a Windows Forms Application, and there is a dialog that should NOT exit when the enter key is pressed, instead it has to validate data first, in case enter was pressed after changing the text of a ComboBox. I've tried by telling it what to do on KeyPress event of the ComboBox if e is the Enter key: Private Sub ComboBoxSizeChoose_KeyPress(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles ComboBoxSizeChoose.KeyPress If e.KeyChar = Convert.ToChar(Keys.Enter) Then Try TamanhoDaNovaFonte = Single.Parse(ComboBoxSizeChoose.Text) Catch ex As Exception Dim Dialogo2 As New Dialog2 Dialog2.ShowDialog() ComboBoxSizeChoose.Text = TamanhoDaNovaFonte End Try End If End Sub But no success so far. When the Enter key is pressed, even with the ComboBox on focus, the whole dialog is closed, returning to the previous form. The validation is NOT done at all, and it has to be done before exiting. In fact, I don't even want to exit on the form's enter KeyPress, the only purpose of the enter key on the whole dialog is to validate the ComboBox (but only when in focus, for the sake of an intuitive UI). I've also tried appending the validation to the KeyPress event of the whole dialog's form, if the key is Enter. NO SUCCESS! It's like my code wasn't there at all. What should I do? (Visual Studio 2008, VB.NET)

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• Multiple Input From Keyboard C# WPF

  - by Alex

  I am writing a Tetris clone in WPF. If I hold down the right arrow key, the current piece shifts right. For playability, I want to allow the user to press another key (i.e. F-key) and rotate the moving piece without having to let go of the right arrow key first. Currently when I do this, the piece stops shifting. My first basic attempt at this was hooking into Window_PreviewKeyDown(object sender, KeyEventArgs e) and then sending a message to the controller layer. How do I structure my input-listening code to allow this? My current code Here

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• Load a list of localized strings at once in IOS

  - by Victor Ronin

  I want to show a table with the list of strings which are localized. The straightforward method would be: a) Point data source to my ViewController b) Define an array c) Allocate the array in my ViewController and init (arrayWithObjects) it with the strings from localized resources (NSLocalizedString) d) Use this array in UITableViewDataSource delegated methods Mainly my concern is item b). The construction looks quite heavy and I wonder whether I can somehow specify and load whole list of localized string at once.

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• Entity Framework 4 Self Many-To-Many with Properties

  - by csharpnoob

  UPDATE: Solved by myself. Tricky but works. If you know a better solution, feel free to correct me. DESIGNER: CODE: Product product1 = new Product{key = "Product 1"}; sd.AddToProducts(product1); Product product2 = new Product{key = "Product 2"}; sd.AddToProducts(product2); Product product3 = new Product{key = "Product 3"}; ProductRelated pr = new ProductRelated(); pr.Products.Add(product1); pr.Products.Add(product2); product3.ProductRelateds.Add(pr); sd.AddToProducts(product3); CODE VIEW: foreach(var x in (from b in sd.Products select b)) { %><%=x.key %><br /> <% foreach (var y in x.ProductRelateds) { foreach (var k in y.Products) { %>- <%=k.key%><br /><%} } } OUTPUT Product1 Product2 Product3 - Product2 - Product1 QUESTION: Hi, i want to have a Self Reference for Releated Products on a Product Entity, something like here: http://my.safaribooksonline.com/9781430227038/modeling_a_many-to-many_comma_self-refer But i also want on the Many-To-Many Reference addional Properties like deleted, created etc. I tried to do it by another Entity "Related", but somehow it won't work. Does anyone had this Problem before? Is there any other Example? Thanks

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• Find if there is an element repeating itself n/k times

  - by gleb-pendler

  You have an array size n and a constant k (whatever) You can assume the the array is of int type (although it could be of any type) Describe an algorithm that finds if there is an element(s) that repeats itself at least n/k times... if there is return one. Do so in linear time (O(n)) The catch: do this algorithm (or even pseudo-code) using constant memory and running over the array only twice

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• How to fetch populated associated models in CakePHP when calling read()

  - by Code Commander

  I have the following Models: class Site extends AppModel { public $name = "Site"; public $useTable = "site"; public $primaryKey = "id"; public $displayField = 'name'; public $hasMany = array('Item' => array('foreignKey' => 'siteId')); public function canView($userId, $isAdmin = false) { if($isAdmin) { return true; } return array_key_exists($this->id, $allowedSites); } } and class Item extends AppModel { public $name = "Item"; public $useTable = "item"; public $primaryKey = "id"; public $displayField = 'name'; public $belongsTo = array('Site' => array('foreignKey' => 'siteId')); public function canView($userId, $isAdmin = false) { // My problem appears to be the next line: return $this->Site->canView($userId, $isAdmin); } } In my controller I am doing something like this: $result = $this->Item->read(null, $this->request->id); // Verify permissions if(!$this->Item->canView($this->Session->read('userId'), $this->Session->read('isAdmin'))) { $this->httpCodes(403); die('Permission denied.'); } I notice that in Item->canView() $this->data['Site'] is populated with the column data from the site table. But it merely an array and not an object. On the other hand $this->Site is a Site object, but it has not been populated with the column data from the site table like $this->data. What is the proper way to have CakePHP get the associated model as the object and containing the data? Or am I going about this all wrong? Thanks!

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• NHibernate / Fluent - Mapping multiple objects to single lookup table

  - by Al

  Hi all I am struggling a little in getting my mapping right. What I have is a single self joined table of look up values of certain types. Each lookup can have a parent, which can be of a different type. For simplicities sake lets take the Country and State example. So the lookup table would look like this: Lookups Id Key Value LookupType ParentId - self joining to Id base class public class Lookup : BaseEntity { public Lookup() {} public Lookup(string key, string value) { Key = key; Value = value; } public virtual Lookup Parent { get; set; } [DomainSignature] [NotNullNotEmpty] public virtual LookupType LookupType { get; set; } [NotNullNotEmpty] public virtual string Key { get; set; } [NotNullNotEmpty] public virtual string Value { get; set; } } The lookup map public class LookupMap : IAutoMappingOverride<DBLookup> { public void Override(AutoMapping<Lookup> map) { map.Table("Lookups"); map.References(x => x.Parent, "ParentId").ForeignKey("Id"); map.DiscriminateSubClassesOnColumn<string>("LookupType").CustomType(typeof(LookupType)); } } BASE SubClass map for subclasses public class BaseLookupMap : SubclassMap where T : DBLookup { protected BaseLookupMap() { } protected BaseLookupMap(LookupType lookupType) { DiscriminatorValue(lookupType); Table("Lookups"); } } Example subclass map public class StateMap : BaseLookupMap<State> { protected StateMap() : base(LookupType.State) { } } Now I've almost got my mappings set, however the mapping is still expecting a table-per-class setup, so is expecting a 'State' table to exist with a reference to the states Id in the Lookup table. I hope this makes sense. This doesn't seem like an uncommon approach when wanting to keep lookup-type values configurable. Thanks in advance. Al

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• Detecting GWT RichTextArea 'dirty' state

  - by David

  I want to detect when the contents of my GWT RichTextArea become 'dirty' (have been changed by the user) in order to enable a 'save' button accordingly. I suppose I could listen for key presses that are likely to have changed the contents; but browser support for key presses is notoriously quirky. I suppose I could, before editing begins, save the original contents in a variable, and upon key press, compare the current contents against that variable, but doing that on each key press is going to be really slow. Is there some neat way to achieve RichTextArea dirty-detection?

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• regex pattern to match only strings that don't contain spaces PHP

  - by Jamex

  Hi, I want to match the word/pattern that is contained in the variable, but only match against the words that don't have white spaces. Please give suggestions. $var = 'look'; $array = ('look', 'greatlook', 'lookgreat', 'look great', 'badlook', 'look bad', 'look ', ' look'); matches words: look, greatlook, lookgreat, badlook non matches: look great, bad look, look (trailing space(s)), (space(s)) look. The syntax of the below functions are OK, but it matches everything $match = preg_grep ("/$var/", $array); $match = preg_grep ("/^$var/", $array); (match words with 'look' at the start) but when I include the [^\s], it gives an error $match = preg_grep ("/$var[^\s]/", $array); Parse error: syntax error, unexpected '^', expecting T_STRING or T_VARIABLE TIA

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• CakePHP - radio button not showing error message

  - by teepusink

  Hi, I'm unable to get the error message to show up when creating a radio form using the CakePHP form helper. This is what I have now. $options=array('active'=>'Active','inactive'=>'Inactive'); echo $form->input('Status', array( 'type' => 'radio', 'id' => 'EntryStatus', 'name' => 'data[Entry][status]', 'options' => $options )); What am I missing? I'm using CakePHP 1.2.7 and this is what I have in the validation 'status' = array( 'notempty' = array( 'rule' = 'notempty', 'required' = true, 'message' = 'yo' ) ) Tried the answer from http://stackoverflow.com/questions/1388823/form-helper-for-creating-radio-button-in-cakephp and it's giving me a select option form instead. Thanks, Tee

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• Exporting dates properly formatted on Google Appengine in Python

  - by Chris M

  I think this is right but google appengine seems to get to a certain point and cop-out; Firstly is this code actually right; and secondly is there away to skip the record if it cant output (like an ignore errors and continue)? class TrackerExporter(bulkloader.Exporter): def __init__(self): bulkloader.Exporter.__init__(self, 'SearchRec', [('__key__', lambda key:key.name(), None), ('WebSite', str, None), ('DateStamp', lambda x: datetime.datetime.strptime(x, '%d-%m-%Y').date(), None), ('IP', str, None), ('UserAgent', str, None)]) Thanks

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• Need example of how to create/manipulate image pixel data with iPhone SDK

  - by whiskeyspider

  Looking for a simple example or link to a tutorial. Say I have a bunch of values stored in an array. I would like to create an image and update the image data from my array. Assume the array values are intensity data and will be updating a grayscale image. Assume the array values are between 0 and 255 -- or that I will convert it to that range. This is not for purposes of animation. Rather the image would be updated based on user interaction. This is something I know how to do well in Java, but am very new to iPhone programming. I've googled some information about CGImage and UIImage -- but am confused as to where to start. Any help would be appreciated.

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• combining dynamic text with regular expressions in php

  - by pfunc

  I am experimenting with finding popular keywords using curl, php and regular expressions. I have an array of non-specific nouns that I am matching my keyword search up. So I am looking for words like "the", "and", "that" etc. and taking them out of the keyword search. so I have an array of words like so: $wordArr = [the, and, at,....]; and then running something like: && preg_match('(\bmyword\w*\b)', $key) == false how do I combine these two so it loops through the array finding out if any of the words in the array match the regular expression? I guess I could just do a for loop, but though maybe I could use in_array($wordArr, $key).. or something like that.

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• help me reason about F# threads

  - by Kevin Cantu

  In goofing around with some F# (via MonoDevelop), I have written a routine which lists files in a directory with one thread: let rec loop (path:string) = Array.append ( path |> Directory.GetFiles ) ( path |> Directory.GetDirectories |> Array.map loop |> Array.concat ) And then an asynchronous version of it: let rec loopPar (path:string) = Array.append ( path |> Directory.GetFiles ) ( let paths = path |> Directory.GetDirectories if paths <> [||] then [| for p in paths -> async { return (loopPar p) } |] |> Async.Parallel |> Async.RunSynchronously |> Array.concat else [||] ) On small directories, the asynchronous version works fine. On bigger directories (e.g. many thousands of directories and files), the asynchronous version seems to hang. What am I missing? I know that creating thousands of threads is never going to be the most efficient solution -- I only have 8 CPUs -- but I am baffled that for larger directories the asynchronous function just doesn't respond (even after a half hour). It doesn't visibly fail, though, which baffles me. Is there a thread pool which is exhausted? How do these threads actually work?

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• using ajax to post comments in cakephp results in 404 error, but no errors locally?

  - by Paul

  Using an ajax helper created for use with Jquery I've created a form that posts comments to "/comments/add", and this works as expected on my local wamp server but not on my production server. On my production server I get a '404 error, cannot find /comments/add'. I've spent quite a bit of time searching for a resolution with no luck so far. I've focused on trying to identify a gap but nothing jumps out at me. Here are some observations: works as expected on local wamp server requestHandler is listed as component files on both local and production server are the same controllers folder has write access autoLayout and autoRender are both set to false Here is the form in my view: <div class="comments form"> <?php echo $ajax->form('/comments/add', 'tournament', array('url' => '/comments/add', 'update' => 'Comments', 'indicator' => 'commentSaved'));?> <fieldset> <legend><?php __('Add Comment');?></legend> <div id="commentSaved" style="display: none; float: right;"> <h2>Loading...</h2> </div> <?php echo $form->hidden('Comment.foreign_id', array('value' => $tournament['Tournament']['id'])); echo $form->hidden('Comment.belongs_to', array('value' => 'Tournament')); echo $form->input('Comment.name'); echo $form->input('Comment.email'); echo $form->input('Comment.web', array('value' => 'http://')); echo $form->input('Comment.content'); ?> </fieldset> <?php echo $form->end('Submit');?> </div> And here is my 'comment's controller add action: function add() { if($this->RequestHandler->isAjax()) { $this->autoLayout = false; $this->autoRender=false; $this->Comment->recursive =-1; $commentInfos = $this->Comment->findAllByIp($_SERVER['REMOTE_ADDR']); $spam = FALSE; foreach($commentInfos as $commentInfo) { if ( time() - strtotime($commentInfo['Comment']['created']) < 180) { $spam = TRUE; } } if ($spam === FALSE) { if (!empty($this->data)) { $this->data['Comment']['ip'] = $_SERVER['REMOTE_ADDR']; $this->Comment->create(); if ($this->Comment->save($this->data)) { $this->Comment->recursive =-1; $comments = $this->Comment->findAll(array('Comment.foreign_id' => $this->data['Comment']['foreign_id'], 'Comment.belongs_to' => $this->data['Comment']['belongs_to'], 'Comment.status' =>'approved')); $this->set(compact('comments')); $this->viewPath = 'elements'.DS.'posts'; $this->render('comments'); } } } else { $this->Comment->recursive =-1; $comments = $this->Comment->findAll(array('Comment.foreign_id' => $this->data['Comment']['foreign_id'], 'Comment.belongs_to' => $this->data['Comment']['belongs_to'], 'Comment.status' =>'approved')); $this->set(compact('comments')); $this->viewPath = 'elements'.DS.'posts'; $this->render('spam'); } } else { $this->Session->setFlash(__('Invalid Action. Please view a post to add a comment.', true)); $this->redirect(array('controller' => 'pages', 'action'=>'display', 'home')); } } As you can see I've made sure that 'autoLayout' and 'autoRender' are set to false, but in Firebug I still get a 404 error stating /comments/add cannot be found on the production server. I should also point out that I'm using jquery, jquery.form and jquery.editable as well as a ajax helper created to be used with jquery. Any help or even suggestions about how to trouble shoot this is really appreciated. Cheers, Paul

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• Jquery effect problem : How to detect if mouseover is triggered by scroll ?

  - by Crupuk

  Hello, I have another problem, and because the reply is to fast here i come back again !! I would like to use "key navigation" and for that, i use the keypress event with down/up key ) When my mouse is over a div (div who's contenaing a big table) and i pull the down key : i scroll to next td + change css style + remove the current style And again, for each event.. So, because my mouse is over the main div, each time i scroll (auto) to a element, the mouseover event is triggered .. And so, the effect is missed.. This is the perfect script : User use keyboard navigation : Mouseover is disabled (so style change only with up/down key) User don't use keyboard : mouseover change the style Could you help me ? The code : $("#content tr").mouseover(function() { $("#content tr.use,#content tr.sel").removeClass("use sel"); $(this).addClass("sel"); }); And the keyboard navigation code : http://pastebin.com/Hgn5Y1FV (Sorry again for my english.. ) Thanks

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• SSL Authentication with Certificates: Should the Certificates have a hostname?

  - by sixtyfootersdude

  Summary JBoss allows clients and servers to authenticate using certificates and ssl. One thing that seems strange is that you are not required to give your hostname on the certificate. I think that this means if Server B is in your truststore, Sever B can pretend to be any server that they want. (And likewise: if Client B is in your truststore...) Am I missing something here? Authentication Steps (Summary of Wikipeida Page) Client Server ================================================================================================= 1) Client sends Client Hello ENCRIPTION: None - highest TLS protocol supported - random number - list of cipher suites - compression methods 2) Sever Hello ENCRIPTION: None - highest TLS protocol supported - random number - choosen cipher suite - choosen compression method 3) Certificate Message ENCRIPTION: None - 4) ServerHelloDone ENCRIPTION: None 5) Certificate Message ENCRIPTION: None 6) ClientKeyExchange Message ENCRIPTION: server's public key => only server can read => if sever can read this he must own the certificate - may contain a PreMasterSecerate, public key or nothing (depends on cipher) 7) CertificateVerify Message ENCRIPTION: clients private key - purpose is to prove to the server that client owns the cert 8) BOTH CLIENT AND SERVER: - use random numbers and PreMasterSecret to compute a common secerate 9) Finished message - contains a has and MAC over previous handshakes (to ensure that those unincripted messages did not get broken) 10) Finished message - samething Sever Knows The client has the public key for the sent certificate (step 7) The client's certificate is valid because either: it has been signed by a CA (verisign) it has been self-signed BUT it is in the server's truststore It is not a replay attack because presumably the random number (step 1 or 2) is sent with each message Client Knows The server has the public key for the sent certificate (step 6 with step 8) The server's certificate is valid because either: it has been signed by a CA (verisign) it has been self-signed BUT it is in the client's truststore It is not a replay attack because presumably the random number (step 1 or 2) is sent with each message Potential Problem Suppose the client's truststore has certs in it: Server A Server B (malicous) Server A has hostname www.A.com Server B has hostname www.B.com Suppose: The client tries to connect to Server A but Server B launches a man in the middle attack. Since server B: has a public key for the certificate that will be sent to the client has a "valid certificate" (a cert in the truststore) And since: certificates do not have a hostname feild in them It seems like Server B can pretend to be Server A easily. Is there something that I am missing?

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