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  • Who architected / designed C++'s IOStreams, and would it still be considered well-designed by today'

    - by stakx
    First off, it may seem that I'm asking for subjective opinions, but that's not what I'm after. I'd love to hear some well-grounded arguments on this topic. In the hope of getting some insight into how a modern streams / serialization framework ought to be designed, I recently got myself a copy of the book Standard C++ IOStreams and Locales by Angelika Langer and Klaus Kreft. I figured that if IOStreams wasn't well-designed, it wouldn't have made it into the C++ standard library in the first place. After having read various parts of this book, I am starting to have doubts if IOStreams can compare to e.g. the STL from an overall architectural point-of-view. Read e.g. this interview with Alexander Stepanov (the STL's "inventor") to learn about some design decisions that went into the STL. What surprises me in particular: It seems to be unknown who was responsible for IOStreams' overall design (I'd love to read some background information about this — does anyone know good resources?); Once you delve beneath the immediate surface of IOStreams, e.g. if you want to extend IOStreams with your own classes, you get to an interface with fairly cryptic and confusing member function names, e.g. getloc/imbue, uflow/underflow, snextc/sbumpc/sgetc/sgetn, pbase/pptr/epptr (and there's probably even worse examples). This makes it so much harder to understand the overall design and how the single parts co-operate. Even the book I mentioned above doesn't help that much (IMHO). Thus my question: If you had to judge by today's software engineering standards (if there actually is any general agreement on these), would C++'s IOStreams still be considered well-designed? (I wouldn't want to improve my software design skills from something that's generally considered outdated.)

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  • Password Cracking in 2010 and Beyond

    - by mttr
    I have looked a bit into cryptography and related matters during the last couple of days and am pretty confused by now. I have a question about password strength and am hoping that someone can clear up my confusion by sharing how they think through the following questions. I am becoming obsessed about these things, but need to spend my time otherwise :-) Let's assume we have an eight-digit password that consists of upper and lower-case alphabetic characters, numbers and common symbols. This means we have 8^96 ~= 7.2 quadrillion different possible passwords. As I understand there are at least two approaches to breaking this password. One is to try a brute-force attack where we try to guess each possible combination of characters. How many passwords can modern processors (in 2010, Core i7 Extreme for eg) guess per second (how many instructions does a single password guess take and why)? My guess would be that it takes a modern processor in the order of years to break such a password. Another approach would consist of obtaining a hash of my password as stored by operating systems and then search for collisions. Depending on the type of hash used, we might get the password a lot quicker than by the bruteforce attack. A number of questions about this: Is the assertion in the above sentence correct? How do I think about the time it takes to find collisions for MD4, MD5, etc. hashes? Where does my Snow Leopard store my password hash and what hashing algorithm does it use? And finally, regardless of the strength of file encryption using AES-128/256, the weak link is still my en/decryption password used. Even if breaking the ciphered text would take longer than the lifetime of the universe, a brute-force attack on my de/encryption password (guess password, then try to decrypt file, try next password...), might succeed a lot earlier than the end of the universe. Is that correct? I would be very grateful, if people could have mercy on me and help me think through these probably simple questions, so that I can get back to work.

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  • TypeError: Error #1009 - (Null reference error) With Flash.

    - by Wind Chimez
    I am not an expert in flash, but i do work with AS and tweak Flash projects , though not having deep expertise in it. Currently i need to revamp a flash website done by one another guy, and the code base given to me, upon execution is throwing the following error. "--- TypeError: Error #1009: Cannot access a property or method of a null object reference. at NewSite_fla::MainTimeline/__setProp_ContactOutP1_ContactOut_Contents_0() at NewSite_fla::MainTimeline/frame1() --" The structure of the project is like, it has the different sections split into different movie clips. There is no single main timeline, but click actions on different areas of seperate movie clips will take them between one another. All the AS logic of event handling are written inline in FLA , no seperate Document class exists. Preloader Movie clip is the first one getting loaded. As i understood the error is getting thrown initially itself, and it is not happening due to any Action script logic written inline, because it is throwing error even before hitting the first inline AS code. I am not able to figure Out what exactly it causing the problem, or where to resolve it. I really got stuck at this point. Any help will be great.I had not seen the particular solution i am looking for anywhere yet, though Error #1009 is common. I uploaded the fla, here ( http://tinyurl.com/249e95p ), for reference.It may not be working , since the included/refered video files and all are not there, but reviwing the action code/movie clips will be possible. Please let me know if somebody will be able to trace the issue exactly.

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  • multithreading issue

    - by vbNewbie
    I have written a multithreaded crawler and the process is simply creating threads and having them access a list of urls to crawl. They then access the urls and parse the html content. All this seems to work fine. Now when I need to write to tables in a database is when I experience issues. I have 2 declared arraylists that will contain the content each thread parse. The first arraylist is simply the rss feed links and the other arraylist contains the different posts. I then use a for each loop to iterate one while sequentially incrementing the other and writing to the database. My problem is that each time a new thread accesses one of the lists the content is changed and this affects the iteration. I tried using nested loops but it did not work before and this works fine using a single thread.I hope this makes sense. Here is my code: SyncLock dlock For Each l As String In links finallinks.Add(l) Next End SyncLock SyncLock dlock For Each p As String In posts finalposts.Add(p) Next End SyncLock ... Dim i As Integer = 0 SyncLock dlock For Each rsslink As String In finallinks postlink = finalposts.Item(i) i = i + 1 finallinks and finalposts are the two arraylists. I did not include the rest of the code which shows the threads working but this is the essential part where my error occurs which is basically here postlink = finalposts.Item(i) i = i + 1 ERROR: index was out of range. Must be non-negative and less than the size of the collection Is there an alternative?

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  • Lookup site column not saving/storing metadata for Office 2007 documents?

    - by Greg Hurlman
    I'm having this issue on several server environments. We have a list at the site collection root. There is a site column created as a multi-value lookup on that list's Title field. This site column is used in document libraries in subsites as a required field. When we upload anything but an Office 2007 document, the user is presented with the document metadata fill-in screen (EditForm.aspx?Mode=Upload), the user fills in the appropriate data (including picking a value(s) for this lookup), and clicks "check in" - the document is checked in as expected, with the lookup field's value filled in. With an Office 2007 document, this fails. The user selected values for the lookup field do not ever make it to the server - no errors are thrown, but the field is not saved with the document. We have an event listener on these document libraries, and if we inspect the incoming SPListItem on the event listener method before a single line of our code has run, we see that the value for the lookup field is null. It smells like a SharePoint bug to me - but before I go calling Microsoft, has anyone seen this & worked around it? Edit: the only entry I see in the SP trace logs relating to the problem: CMS/Publishing/8ztg/Medium/Got List Item Version, but item was null

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  • Why does the Java Collections Framework offer two different ways to sort?

    - by dvanaria
    If I have a list of elements I would like to sort, Java offers two ways to go about this. For example, lets say I have a list of Movie objects and I’d like to sort them by title. One way I could do this is by calling the one-argument version of the static java.util.Collections.sort( ) method with my movie list as the single argument. So I would call Collections.sort(myMovieList). In order for this to work, the Movie class would have to be declared to implement the java.lang.Comparable interface, and the required method compareTo( ) would have to be implemented inside this class. Another way to sort is by calling the two-argument version of the static java.util.Collections.sort( ) method with the movie list and a java.util.Comparator object as it’s arguments. I would call Collections.sort(myMovieList, titleComparator). In this case, the Movie class wouldn’t implement the Comparable interface. Instead, inside the main class that builds and maintains the movie list itself, I would create an inner class that implements the java.util.Comparator interface, and implement the one required method compare( ). Then I'd create an instance of this class and call the two-argument version of sort( ). The benefit of this second method is you can create an unlimited number of these inner class Comparators, so you can sort a list of objects in different ways. In the example above, you could have another Comparator to sort by the year a movie was made, for example. My question is, why bother to learn both ways to sort in Java, when the two-argument version of Collections.sort( ) does everything the first one-argument version does, but with the added benefit of being able to sort the list’s elements based on several different criteria? It would be one less thing to have to keep in your mind while coding. You’d have one basic mechanism of sorting lists in Java to know.

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  • Qt - QWebView Problem

    - by user547057
    Hi, I have a PyQt gui script which consists of a QWebView widget. I'm trying to send a GET request, i.e go to a page, fill a form and hit click using the code at the bottom of this question. Since i'm dealing with the documentElement(a QWebElement) of the webview, I need to place all DOM actions in a separate function(which I have named fillForm) and connect the loadFinished() signal into the function. Without connecting the signal, the document will not have loaded and I won't be able to get the elements I want. I'm able to submit the form correctly and get the proper response from the webpage. The problem i'm having is that, the above leads to a sort of infinite loop. This is because the webpage gets reloaded each time a new page is loaded, so the form gets filled each and every single time without stopping. I'd like to know if there's some way of finding out whether the WebView's page has loaded fully, non-asynchronously or maybe pause execution of the script(without freezing the gui) until the whole document has loaded. I'm unable to come up with a satisfactory solution(my idea consisted of keeping a global variable to track clicks) to this problem. I would appreciate it if someone could help me out with a better way to tackle this. Thanks! Here's the code i'm using import sys from PyQt4.QtCore import * from PyQt4.QtGui import * from PyQt4.QtWebKit import * from PyQt4 import QtCore app = QApplication(sys.argv) web = QWebView() web.load(QUrl("http://mywebsite.com")) def fillForm(): doc = web.page().mainFrame().documentElement() searchform = doc.findFirst("input[type=text]") searchform.setAttribute("value", "hello") button = doc.findFirst("input[type=submit]") button.evaluateJavaScript("click()") QtCore.QObject.connect(web, QtCore.SIGNAL("loadFinished"), fillForm) web.show() sys.exit(app.exec_())

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  • Django FormWizard with dynamic forms

    - by krys
    I want to implement a simple 2 part FormWizard. Form 1 will by dynamically generated something like this: class BuyAppleForm(forms.Form): creditcard = forms.ChoiceField(widget = forms.RadioSelect) type = forms.ChoiceField(widget = forms.RadioSelect) def __init__(self,*args, **kwargs): user = kwargs['user'] del kwargs['user'] super(BuyAppleForm, self).__init__(*args, **kwargs) credit_cards = get_credit_cards(user) self.fields['creditcard'].choices = [(card.id,str(card)) for card in credit_cards] apple_types= get_types_packages() self.fields['type'].choices = [(type.id,str(type)) for type in apple_types] This will dynamically create a form with lists of available choices. My second form, I actually want no input. I just want to display a confirmation screen containing the credit card info, apple info, and money amounts (total, tax, shipping). Once user clicks OK, I want the apple purchase to commence. I was able to implement the single form way by passing in the request.user object in the kwargs. However, with the FormWizard, I cannot figure this out. Am I approaching the problem wrong and is the FormWizard not the proper way to do this? If it is, how can the Form __init__ method access the user object from the HTTP request?

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  • Patterns for non-layered applications

    - by Paul Stovell
    In Patterns of Enterprise Application Architecture, Martin Fowler writes: This book is thus about how you decompose an enterprise application into layers and how those layers work together. Most nontrivial enterprise applications use a layered architecture of some form, but in some situations other approaches, such as pipes and filters, are valuable. I don't go into those situations, focussing instead on the context of a layered architecture because it's the most widely useful. What patterns exist for building non-layered applications/parts of an application? Take a statistical modelling engine for a financial institution. There might be a layer for data access, but I expect that most of the code would be in a single layer. Would you still expect to see Gang of Four patterns in such a layer? How about a domain model? Would you use OO at all, or would it be purely functional? The quote mentions pipes and filters as alternate models to layers. I can easily imagine a such an engine using pipes as a way to break down the data processing. What other patterns exist? Are there common patterns for areas like task scheduling, results aggregation, or work distribution? What are some alternatives to MapReduce?

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  • Wordpress creating plugin for most viewed posts problem?

    - by user303832
    Hello,I just want to create plugin that will when visitor(user,visitor,...) visit some post,remember what post,and to increment counter of that post,I wrote this code,but sometimes,counter is incremented,even post isn't viewed,or post with other Id is added to a table.Can someone help me with this,please.I know that there are plugins for this that I'm trying to do,but still want to write this plugin. function IncrementPostCount($the_content) { global $post; global $wpdb; if(($post->post_status == 'publish') && (int)$post->ID) { if(is_single()) { // just for single post - not for page $postID = (int)$post->ID; $postTitle = urlencode($post->post_title); $postLink = urlencode(get_permalink($post->ID)); $oneRow = $wpdb->get_row("SELECT * FROM wp_postovi WHERE postAjDi='$postID'"); if(empty ($oneRow)) { $postCounter = 1; $data_array = array( 'readnTimes' => $postCounter, 'linkPost'=>$postLink, 'TitlePost'=>$postTitle, 'postAjDi'=>$postID); $wpdb->insert('wp_najcitaniji_postovi', $data_array); } else { $postCounter = intval($oneRow->readnTimes) + 1; $data_array = array('readnTimes' => $postCounter); $where_array = array('postAjDi'=>intval($oneRow->postAjDi)); $wpdb->update('wp_postovi',$data_array,$where_array); } return $the_content; } return $the_content; } } add_filter('the_content','IncrementPostCount'); Sorry on my bad english,tnx in advance.

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  • Maven - Include dependent libs in jar without unpacking dependencies?

    - by Marcus
    We're trying to build a client jar that includes unpacked depenedent jar's. And the manifest should have class-path entries to the dependent jars. The snippet below works but the jars are unpacked - how can we stop the jars from being unpacked? <plugin> <artifactId>maven-assembly-plugin</artifactId> <configuration> <descriptorRefs> <descriptorRef>jar-with-dependencies</descriptorRef> </descriptorRefs> <archive> <manifest> <addClasspath>true</addClasspath> </manifest> </archive> </configuration> <executions> <execution> <id>make-assembly</id> <phase>package</phase> <goals> <goal>single</goal> </goals> </execution> </executions> </plugin>

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  • Time Machine for Windows?

    - by Blub
    Finally got convinced to start using some kind of version control for my code instead of zipping down a copy of the project at the end of each day. Downloaded Tortoise SVN and used it to create a repository localy on my hdd. I've been using it for 2 days now but I have to say that using it is actually more hassle than just copying the project manually in explorer. Sure, you only store incremental changes but with the cheap disks of today I can't really say that's an argument when you only have small projects. I haven't realy found a quick way to browse the older versions of my files eighter. What I want is an infinite undo that is completely transparent while I code, if I save the file I want a backup. I don't want to check out, check in and don't even get me started on moving files. I haven't tried Time Machine for OS X but it looks like it's exactly what I'm looking for. Does such a program exist for windows? Preferably free and with some kind of tagging-system so I can tag a timestamp when the project is working etc. Maybe should add that I mostly work alone on a single computer. Update: Some of you asked why I want backup. Since I work alone it's mostly to allow me to quickly hack up a solution without worrying that something will screw up.

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  • C# WPF abnormal CPU usage for animation

    - by 0xDEAD BEEF
    I am developing WPF application and client reports extreamly high CPU usage (90%) (whereas i am unable to repeat that behavior). I have traced bootleneck down to these lines. It is simple glowing animation for small single led control (blinking led). What could be reason for this simple annimation taking up SO huge CPU resources? <Trigger Property="State"> <Trigger.Value> <local:BlinkingLedStatus>Blinking</local:BlinkingLedStatus> </Trigger.Value> <Trigger.EnterActions> <BeginStoryboard Name="beginStoryBoard"> <Storyboard> <DoubleAnimation Storyboard.TargetName="glow" Storyboard.TargetProperty="Opacity" AutoReverse="True" From="0.0" To="1.0" Duration="0:0:0.5" RepeatBehavior="Forever"/> </Storyboard> </BeginStoryboard> </Trigger.EnterActions> <Trigger.ExitActions> <StopStoryboard BeginStoryboardName="beginStoryBoard"/> </Trigger.ExitActions> </Trigger>

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  • Establishing persistent connection to a database in Java

    - by gmile
    I've ran through several examples over the web, and found that every single time I need something from the DB, I should write the following code: try { // Step 1: Load the JDBC driver. Class.forName("mysql_driver_name"); // Step 2: Establish the connection to the database. String url = "jdbc:string_to_mysql_server"; Connection conn = DriverManager.getConnection(url,"user1","password"); // fetch from the DB ... } catch (Exception e) { System.err.println("Got an exception! "); System.err.println(e.getMessage()); } It's very annoying to put up this code every time I want something from the DB, so the question is - is there a way to only once connect entirely all my app to the DB somehow at the very start point, avoiding copy-pasting mentioned code, and then be able to do everything I want with DB? I've quickly looked through NetBeans's Project menu, but didn't find any clue on how to configurate a persistent connection to a selected DB. If it's important, i'm writing a purely desktop app, i.e. using Java EE. Also, it's worth mentioning that I'm a kinda beginner in Java.

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  • Java SSH2 libraries in depth: Trilead/Ganymed/Orion [/other?]

    - by Bernd Haug
    I have been searching for a pure Java SSH library to use for a project. The single most important needed feature is that it has to be able to work with command-line git, but remote-controlling command-line tools is also important. A pretty common choice, e.g. used in the IntelliJ IDEA git integration (which works very well), seems to be Trilead SSH2. Looking at their website, it's not being maintained any more. Trilead seems to have been a fork of Ganymed SSH2, which was a ETH Zurich project that didn't see releases for a while, but had a recent release by its new owner, Christian Plattner. There is another actively maintained fork from that code base, Orion SSH, that saw an even more recent release, but which seems to get mentioned online much less than the other 2 forks. Has anybody here worked with any of (or, if possible, both) of Ganymed and Orion and could kindly describe the development experience with either/both? Accuracy of documentation [existence of documentation?], stability, buggyness... - all of these would be highly interesting to me. Performance is not so important for my current project. If there is another pure-Java SSH implementation that should be used instead, please feel free to mention it, but please don't just mention a name...describe your judgment from actual experience. Sorry if this question may seem a bit "do my homework"-y, but I've really searched for reviews. Everything out there seems to be either a listing of implementations or short "use this! it's great!" snippets.

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  • Why is creating a ring buffer shared by different processes so hard (in C++), what I am doing wrong?

    - by recipriversexclusion
    I am being especially dense about this but it seems I'm missing an important, basic point or something, since what I want to do should be common: I need to create a fixed-size ring buffer object from a manager process (Process M). This object has write() and read() methods to write/read from the buffer. The read/write methods will be called by independent processes (Process R and W) I have implemented the buffer, SharedBuffer<T&>, it allocates buffer slots in SHM using boost::interprocess and works perfectly within a single process. I have read the answers to this question and that one on SO, as well as asked my own, but I'm still in the dark about how to have different processes access methods from a common object. The Boost doc has an example of creating a vector in SHM, which is very similar to what I want, but I want to instantiate my own class. My current options are: Use placement new, as suggested by Charles B. to my question; however, he cautions that it's not a good idea to put non-POD objects in SHM. But my class needs the read/write methods, how can I handle those? Add an allocator to my class definition, e.g. have SharedBuffer<T&, Alloc> and proceed similarly to the vector example given in boost. This sounds really complicated. Change SharedBuffer to a POD class, i.e. get rid of all the methods. But then how to synchronize reading and writing between processes? What am I missing? Fixed-length ring buffers are very common, so either this problem has a solution or else I'm doing something wrong.

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  • How to nest joins with CakePHP?

    - by Daren Thomas
    I'm trying to behave. So, instead of using following SQL syntax: select * from tableA INNER JOIN tableB on tableA.id = tableB.tableA_id LEFT OUTER JOIN ( tableC INNER JOIN tableD on tableC.tableD_id = tableD.id) on tableC.tableA_id = tableA.id I'd like to use the CakePHP model->find(). This will let me use the Paginator too, since that will not work with custom SQL queries as far as I understand (unless you hardcode one single pagination query to the model which seems a little inflexible to me). What I've tried so far: /* inside tableA_controller.php, inside an action, e.g. "view" */ $this->paginate['recursive'] = -1; # suppress model associations for now $this->paginate['joins'] = array( array( 'table' => 'tableB', 'alias' => 'TableB', 'type' => 'inner', 'conditions' => 'TableB.tableA_id = TableA.id', ), array( 'table' => 'tableC', 'alias' => 'TableC', 'type' => 'left', 'conditions' => 'TableC.tableA_id = TableA.id', 'joins' = array( # this would be the obvious way to do it, but doesn't work array( 'table' => 'tableD', 'alias' => 'TableD', 'type' => 'inner', 'conditions' => 'TableC.tableD_id = TableD.id' ) ) ) ) That is, nesting the joins into the structure. But that doesn't work (CakePHP just ignores the nested 'joins' element which was kind of what I expected, but sad. I have seen hints in comments on how to do subqueries (in the where clause) using a statement builder. Can a similar trick be used here?

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  • Linked List Sorting with Strings In C

    - by user308583
    I have a struct, with a Name and a single Node called nextName It's a Singly Linked list, and my task is to create the list, based on alphabetical order of the strings. So iff i enter Joe Zolt and Arthur i should get my list structured as Joe Than Joe Zolt Than Arthur Joe Zolt I'm having trouble implementing the correct Algorithm, which would put the pointers in the right order. This is What I have as of Now. Temp would be the name the user just entered and is trying to put into the list, namebox is just a copy of my root, being the whole list if(temp != NULL) { struct node* namebox = root; while (namebox!=NULL && (strcmp((namebox)->name,temp->name) <= 0)) { namebox = namebox->nextName; printf("here"); } temp->nextName = namebox; namebox = temp; root = namebox; This Works right now, if i enter names like CCC BBB than AAA I Get Back AAA BBB CCC when i print But if i put AAA BBB CCC , When i print i only get CCC, it cuts the previous off.

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  • How to restart a wcf server from within a client?

    - by djerry
    Hey guys, I'm using Wcf for server - client communication. The server will need to run as a service, so there's no GUI. The admin can change settings using the client program and for those changes to be made on server, it needs to restart. This is my server setup NetTcpBinding binding = new NetTcpBinding(SecurityMode.Message); Uri address = new Uri("net.tcp://localhost:8000"); //_svc = new ServiceHost(typeof(MonitoringSystemService), address); _monSysService = new MonitoringSystemService(); _svc = new ServiceHost(_monSysService, address); publishMetaData(_svc, "http://localhost:8001"); _svc.AddServiceEndpoint(typeof(IMonitoringSystemService), binding, "Monitoring Server"); _svc.Open(); MonitoringSystemService is a class i'm using to handle client - server comm. It looks like this: [CallbackBehavior(ConcurrencyMode = ConcurrencyMode.Reentrant)] [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, MaxItemsInObjectGraph = 2147483647)] public class MonitoringSystemService : IMonitoringSystemService {} So i need to call a restart method on the client to the server, but i don't know how to restart (even stop - start) the server. I hope i'm not missing any vital information. Thanks in advance.

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  • Delphi Unicode String Type Stored Directly at its Address (or "Unicode ShortString")

    - by Andreas Rejbrand
    I want a string type that is Unicode and that stores the string directly at the adress of the variable, as is the case of the (Ansi-only) ShortString type. I mean, if I declare a S: ShortString and let S := 'My String', then, at @S, I will find the length of the string (as one byte, so the string cannot contain more than 255 characters) followed by the ANSI-encoded string itself. What I would like is a Unicode variant of this. That is, I want a string type such that, at @S, I will find a unsigned 32-bit integer (or a single byte would be enough, actually) containing the length of the string in bytes (or in characters, which is half the number of bytes) followed by the Unicode representation of the string. I have tried WideString, UnicodeString, and RawByteString, but they all appear only to store an adress at @S, and the actual string somewhere else (I guess this has do do with reference counting and such). Update: The most important reason for this is probably that it would be very problematic if sizeof(string) were variable. I suspect that there is no built-in type to use, and that I have to come up with my own way of storing text the way I want (which actually is fun). Am I right? Update I will, among other things, need to use these strings in packed records. I also need manually to read/write these strings to files/the heap. I could live with fixed-size strings, such as <= 128 characters, and I could redesign the problem so it will work with null-terminated strings. But PChar will not work, for sizeof(PChar) = 1 - it's merely an address. The approach I eventually settled for was to use a static array of bytes. I will post my implementation as a solution later today.

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  • PHP: Aggregate Model Classes or Uber Model Classes?

    - by sunwukung
    In many of the discussions regarding the M in MVC, (sidestepping ORM controversies for a moment), I commonly see Model classes described as object representations of table data (be that an Active Record, Table Gateway, Row Gateway or Domain Model/Mapper). Martin Fowler warns against the development of an anemic domain model, i.e. a class that is nothing more than a wrapper for CRUD functionality. I've been working on an MVC application for a couple of months now. The DBAL in the application I'm working on started out simple (on account of my understanding - oh the benefits of hindsight), and is organised so that Controllers invoke Business Logic classes, that in turn access the database via DAO/Transaction Scripts pertinent to the task at hand. There are a few "Entity" classes that aggregate these DAO objects to provide a convenient CRUD wrapper, but also embody some of the "behaviour" of that Domain concept (for example, a user - since it's easy to isolate). Taking a look at some of the code, and thinking along refactoring some of the code into a Rich Domain Model, it occurred to me that were I to try and wrap the CRUD routines and behaviour of say, a Company into a single "Model" class, that would be a sizeable class. So, my question is this: do Models represent domain objects, business logic, service layers, all of the above combined? How do you go about defining the responsibilities for these components?

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  • php: replacing double <br /> with </p><p>

    - by andufo
    i use nicEdit to write RTF data in my CMS. The problem is that it generates strings like this: hello first line<br><br />this is a second line<br />this is a 3rd line since this is for a news site, i much prefer the final html to be like this: <p>hello first line</p><p>this is a second line<br />this is a 3rd line</p> so my current solution is this: i need to trim the $data for <br /> at the start/end of the string replace <br /><br /> with </p><p> (one single <br /> is allowed). finally, add <p> at the start and </p> at the end i only have the 3rd step so far. can someone give me a hand with steps 1 and 2? function replace_br($data) { # step 3 $data = '<p>'.$data.'</p>'; return $data; } thanks! ps: it would be even better to avoid specific situations. example: "hello<br /><br /><br /><br /><br />too much space" -- those 5 breaklines should also be converted to just one "</p><p>"

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  • rails: has_many :through validation?

    - by ramonrails
    Rails 2.1.0 (Cannot upgrade for now due to several constraints) I am trying to achieve this. Any hints? A project has many users through join model A user has many projects through join model Admin class inherits User class. It also has some Admin specific stuff. Admin like inheritance for Supervisor and Operator Project has one Admin, One supervisor and many operators. Now I want to 1. submit data for project, admin, supervisor and operator in a single project form 2. validate all and show errors on the project form. Project has_many :projects_users ; has_many :users, :through => :projects_users User has_many :projects_users ; has_many :projects, :through => :projects_users ProjectsUser = :id integer, :user_id :integer, :project_id :integer, :user_type :string ProjectUser belongs_to :project, belongs_to :user Admin < User # User has 'type:string' column for STI Supervisor < User Operator < User Is the approach correct? Any and all suggestions are welcome.

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  • java.security.AccessControlException : access denied (java.util.PropertyPermission http.agent read)

    - by Stefano Borini
    I have a non-signed java applet interacting with the same host. Every time I click on an element in my page, the applet (which is a third part applet I have no control on) should load data from a URL. I say should, because for some files, I get java.security.AccessControlException : access denied (java.util.PropertyPermission http.agent read) and some other files are correctly loaded. All files are correctly readable and downloadable from the web server, and they are very simple text files. I also found that, in some cases, files that previously returned the error are now loaded and continue to load, so it seems a cache is involved somehow. Does any of you have an idea of what's going on here ? The behavior seems to be absolutely random, and I have no way of performing debug on this thing. Note: I used this applet to perform many other "single shot" file access, and it never gave me any problem. The only apparent difference I have is that now I do it "on-demand" via a javascript event. What could be the cause, in the java of the applet or anywhere else ?

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  • Oracle doesn't remove cursors after closing result set

    - by Vladimir
    Note: we reuse single connection. ************************************************ public Connection connection() {                try {            if ((connection == null) || (connection.isClosed()))            {               if (connection!=null) log.severe("Connection was closed !");                connection = DriverManager.getConnection(jdbcURL, username, password);            }        } catch (SQLException e) {            log.severe("can't connect: " + e.getMessage());        }        return connection;            } ************************************************** public IngisObject[] select(String query, String idColumnName, String[] columns) { Connection con = connection(); Vector<IngisObject> objects = new Vector<IngisObject>(); try {     Statement stmt = con.createStatement();     String sql = query;     ResultSet rs =stmt.executeQuery(sql);//oracle increases cursors count here     while(rs.next()) {        IngisObject o = new IngisObject("New Result");        o.setIdColumnName(idColumnName);                    o.setDatabase(this);        for(String column: columns) o.attrs().put(column, rs.getObject(column));        objects.add(o);        }     rs.close();// oracle don't decrease cursor count here, while it's expected     stmt.close();     } catch (SQLException ex) {     System.out.println(query);     ex.printStackTrace(); }

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