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  • XSLT 1 Plain Text Spacing

    - by justkt
    Using Perl's XML::LibXSLT necessitates that I use XSLT 1.0, which means that I am stuck without XSLT 2.0 features. Is there a way that I can still pad text cleanly in a plain-text output from my processing? What I want is: <values> <headers> <header>Header 1</header> <header>Header 2</header> </headers> <value> <one>First value 1</one> <two>First value 2</two> </value> <value> <one>Second value 1</one> <two>Second value 2</two> </value> .... <value> <one>Nth value 1</one> <two>Nth value 2</two> </value> </values> To become Header 1 Header 2 First value 1 First value 2 Second value 1 Second value 2 .... Nth value 1 Nth value 2 I realize that XSLT isn't necessarily ideally suited for this type of formatting, but the data will likely also be formatted in other ways.

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  • Choosing approach for an IM client-server app

    - by John
    Update: totally re-wrote this to be more succint. I'm looking at a new application, one part of which will be very similar to standard IM clients, i.e text chat, ability to send attachments, maybe some real-time interaction like a multi-user whiteboard. It will be client-server, i.e all traffic goes through my central server. That means if I want to support cross-communication with other IM systems, I am still free to pick any protocol for my own client<--server communication - my server can use XMPP or whatever to talk to other systems. Clients are expected to include desktop apps, but probably also browser-based as well either through Flex/Silverlight or HTML/AJAX. I see 3 options for my own client-server communication layer: XMPP. The benefits are clients already exist as do open-source servers. However it requires the most up-front research/learning and also appears like it might raise legal issues due to GPL. Custom sockets. A server app makes connections with the clients, allowing any text/binary data to be sent very fast. However this approach requires building said server from scratch, and also makes a JS client tricky Servlets (or similar web server). Using tried and tested Java web-stack, clients send HTTP requests similar to AJAX-based websites. The benefit is the server is easy to write using well-established technologies, and easy to talk to. But what restrictions would this bring? Is it appropriate technology for real-time communication? Advice and suggests are welcome, especially what pros and cons surround using a web-server approach as compared to a socket-based approach.

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  • HTML Table: How to resize data cells when already specified "colspan"?

    - by Jenny
    I have tabular data to display, which has a meaning to both rows and columns. Columns are time blocks, rows are days. A particular datacell is confined to a single day, but can be in multiple time block. To show this, I am using the colspan tag. <div id = "GuideTable"> <table> <tr> <td colspan = 3> </td></tr></table> </div> Or Whatever. I'm trying to apply CSS formating to the entire table, and for changing colors, etc, things are fine, but wanting to have a consistent width is where I am running into problems. Right now, each data cell's width seems tied to the maximum width in its column (everything auto lines up). Some columns are itty bitty, others are huge. I'm trying to make columns consistently sized (even if that means every column is as big as the biggest column needs to be), but setting an individual datacells width (either via css or in the tag itself) is getting me nowhere. I'm thinking maybe the colspan tag is overriding my manual width? If that's the case, how can I change the width of a column as a whole, especially since they aren't explicitly defined? (CAN you explicitly define columns?) Examples of the CSS I'm using: #GuideTable td{ background:#ffffff; border-style: solid; border-width: 1px; width: 100px; }

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  • What would happen if a same file being read and appended at the same time(python programming)?

    - by Shane
    I'm writing a script using two separate thread one doing file reading operation and the other doing appending, both threads run fairly frequently. My question is, if one thread happens to read the file while the other is just in the middle of appending strings such as "This is a test" into this file, what would happen? I know if you are appending a smaller-than-buffer string, no matter how frequently you read the file in other threads, there would never be incomplete line such as "This i" appearing in your read file, I mean the os would either do: append "This is a test" - read info from the file; or: read info from the file - append "This is a test" to the file; and such would never happen: append "This i" - read info from the file - append "s a test". But if "This is a test" is big enough(assuming it's a bigger-than-buffer string), the os can't do appending job in one operation, so the appending job would be divided into two: first append "This i" to the file, then append "s a test", so in this kind of situation if I happen to read the file in the middle of the whole appending operation, would I get such result: append "This i" - read info from the file - append "s a test", which means I might read a file that includes an incomplete string?

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  • C# Automatic Properties - Still null after +=?

    - by Sam Schutte
    This seems like a bug to me... I accept that automatic properties, defined as such: public decimal? Total { get; set; } Will be null when they are first accessed. They haven't been initialized, so of course they are null. But, even after setting their value through +=, this decimal? still remains null. So after: Total += 8; Total is still null. How can this be correct? I understand that it's doing a (null + 8), but seems strange that it doesn't pick up that it means it should just be set to 8... Addendums: I made the "null + 8" point in my question - but notice that it works with strings. So, it does null + "hello" just fine, and returns "hello". Therefore, behind the scenes, it is initializing the string to a string object with the value of "hello". The behavior should be the same for the other types, IMO. It might be because a string can accept a null as a value, but still, a null string is not an initialized object, correct? Perhaps it's just because a string isn't a nullable...

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  • How do I setup model associations in an RSpec test?

    - by Eric M.
    I've pastied the specs I've written for the posts/show.html.erb view in an application I'm writing as a means to learn RSpec. I am still learning about mocks and stubbing. This question is specific to the "should list all related comments" spec. What I want is to test that the show view displays a post's comments. But what I'm not sure about is how to setup this test and then have the test iterate through with should contain('xyz') statements. Any hints? Other suggestions are also appreciated! Thanks. ---Edit Some more information. I have a named_scope applied to comments in my view (I know, I did this a bit backwards in this case), so @post.comments.approved_is(true). The code pastied responds with the error "undefined method `approved_is' for #", which makes sense since I told it stub comments and return a comment. I'm still not sure, however, how to chain the stubs so that @post.comments.approved_is(true) will return an array of comments.

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  • Login failed for user ''. The user is not associated with a trusted SQL Server connection

    - by Tony_Henrich
    My web service app on my Windows XP box is trying to log in to my sql server 2005 database on the same box. The machine is part of a domain. I am logged in in the domain and I am an admin on my machine. I am using Windows Authentication in my connection string as in "Server=myServerAddress;Database=myDataBase;Trusted_Connection=True". SQLServer is configured for both types of authentication (mixed mode) and accepts remote connections and accepts tcp and named pipes protocols. Integrated authentication is enabled in IIS and with and without anonymous access. 'Everyone' has access to computer from network setting in local security settings. ASPNET is a user in the sql server and has access to the daatabase. user is mapped to the login. The app works fine for other developers which means the app shouldn't be changed (It's not new code). So it seems it's my machine which has an issue. I am getting the error "Login failed for user ''. The user is not associated with a trusted SQL Server connection" Note the blank user name. Why am I getting this error when both the app and database are on my machine? I can use SQL Server authentication but don't want to. I can connect to the database using SSMS and my Windows credentials. It might be related to setspn, kerberos, delegation, AD. I am not sure what further checks to make?

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  • Declaring an object of a conditional type with a System.Type

    - by Chapso
    I am attempting to launch a specific form depending on the selected node of a treeview on the doubleclick event. The code I need to use to launch the form is a little bulky becuase I have to ensure that the form is not disposed, and that the form is not already open, before launching a new instance. I'd like to have all of this checking happen in one place at the end of the function, which means that I have to be able to pass the right form type to the code at the end. I'm trying to do this with a System.Type, but that doesn't seem to be working. Could someone point me in the right direction, please? With TreeView.SelectedNode Dim formType As Type Select Case .Text Case "Email to VPs" formType = EmailForm.GetType() Case "Revise Replacers" formType = DedicatedReplacerForm.GetType() Case "Start Email" formType = EmailForm.GetType() End Select Dim form As formType Dim form As formType Try form = CType(.Tag, formType) If Not form.IsDisposed Then form.Activate() Exit Sub End If Catch ex As NullReferenceException 'This will error out the first time it is run as the form has not yet ' been defined. End Try form = New formType form.MdiParent = Me .Tag = form CType(TreeView.SelectedNode.Tag, Form).Show() End With

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  • Java: Cleaing up connection reset (but not by peer).

    - by Zombies
    There seems to be some confusion as well contradicting statements on various SO answers: http://stackoverflow.com/questions/585599/whats-causing-my-java-net-socketexception-connection-reset . You can see here that the accepted answer states that the connecteion was closed by other side. But this is not true, closing a connection doesn't cause a connection reset. It is cauesed by "an underlying TCP/IP error." What I want to know is if a SocketException: Connection reset means really besides "unerlying TCP/IP Error." What really causes this? As I doubt it has anything to do with the connection being closed (since closing a connection isn't an exception worthy flag, and reading from a closed connection is, but that isn't an "underlying TCP/IP error." My hypothesis is this Connection reset is caused from a server's failure to acknowledge an ACK packet (either wholly or just improperly as per TCP/IP). And that a SocketTimeoutException is generated only when no data is generated to be read (since this is thrown during a read after a certain duration, and read is waiting for data, but is not concerned with ACK packets). In other words, read() throws SocketTimeoutException if it didn't read any bytes of actual data (DATA LAYER) in its allotted time.

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  • How do I get my Windows Forms application to use a custom main function and get access to the Applic

    - by burble
    Hi Folks I am trying to use a Main () function in a class to control the program flow in my vb .net Windows Forms application. I have added a splash screen component and a login screen, and customised my main sdi form. I have set the startup form to be my main function in the Application Page of the Project Designer, and everything seems to work fine(ish). However, I would like to use: Me.MinimumSplashScreenDisplayTime = 5000 to ensure that the splash screen is visible, but it is not recognised by the system unless I tick the Enable Application Framework check box on the Project Designer. If I do this, on startup the program ignores the login and splash screens and all my customisation and just displays a default Form1, even though I have also specified my splash screen in the AF dropdown list. Of course, there are alternative ways to delay a splash screen, such as putting the thread temporarily to sleep (which didn't seem to work), but I suspect that there are other things in the AF that I may want to use. Any suggestions on how I can get round this please, and get a sensible means of controlling program flow? Any thoughts on the best overall structure for organising program flow would also be helpful too. I am concerned both about going down a Microsoft or an alternative custom route that may cause me problems later, as the application becomes more complex. Thankses.

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  • Calculating collission for a moving circle, without overlapping the boundaries

    - by Robert Vella
    Let's say I have circle bouncing around inside a rectangular area. At some point this circle will collide with one of the surfaces of the rectangle and reflect back. The usual way I'd do this would be to let the circle overlap that boundary and then reflect the velocity vector. The fact that the circle actually overlaps the boundary isn't usually a problem, nor really noticeable at low velocity. At high velocity it becomes quite clear that the circle is doing something it shouldn't. What I'd like to do is to programmitically take reflection into account and place the circle at it's proper position before displaying it on the screen. This means that I have to calculate the point where it hits the boundary between it's current position and it's future position -- rather than calculating it's new position and then checking if it has hit the boundary. This is a little bit more complicated than the usual circle/rectangle collission problem. I have a vague idea of how I should do it -- basically create a bounding rectangle between the current position and the new position, which brings up a slew of problems of it's own (Since the rectangle is rotated according to the direction of the circle's velocity). However, I'm thinking that this is a common problem, and that a common solution already exists. Is there a common solution to this kind of problem? Perhaps some basic theories which I should look into?

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  • Chrome.tabs.getSelected() doesn't work. What am I doing wrong ?

    - by warv3n
    Hi there ! I'm building my first GC extension, and I am having a problem using this function. I would like to get the url of the current tab, and to do so (after some google research, of course), I use the chrome.tabs.getSelected() function. Here it is in my code : ... socket.onopen = function(msg){ log("Welcome - status " + this.readyState); chrome.tabs.getSelected(null, function(tab){ sendUrl(tab.url); }); }; function sendUrl(tabUrl) { socket.send("#URL#"+ tabUrl); } The socket.open is a listener for the Websocket API I use in my extension. The log function print the status of the socket (1, which means it's OPEN or connected and ready to communicate, according to the Websocket API), but the chrome.tabs.getSelected() function do not seems to work, as the server do not receive anything (the socket is not the problem here, I tried to send a test message with socket.send() instead of chrome.tabs.getSelected() and the server received it). I put the permissions: ["tabs"] into the manifest.json so I can use this function. So I don't know what I am doing wrong here ? I also tried to put chrome.tab.getSelected() elsewhere in the code, but it is still not working. Any help is welcome :)

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  • Is it OK to set state within Event Raising methods?

    - by Greg
    I ran across this pattern in the code of a library I'm using. It sets state within the event raising method, but only if the event is not null. protected virtual void OnMyEvent(EventArgs e) { if(MyEvent != null) { State = "Executing"; // Only sets state if MyEvent != null. MyEvent(this,e); } } Which means that the state is not set when overriding the method: protected override void OnMyEvent(EventArgs e) { base.OnMyEvent(e); Debug.Assert( State == "Executing" ); // This fails } but is only set when handling the event: foo.MyEvent += (o, args) => Debug.Assert(State == "Executing"); // This passes Setting state within the if(MyEvent != null) seems like bad form, but I've checked the Event Design Guidelines and it doesn't mention this. Do you think this code is incorrect? If so, why? (Reference to design guidelines would be helpful). Edit for Context: It's a Control, I'm trying to create subclass of it, and the state that it's setting is calling EnsureChildControls() conditionally based upon there being an event handler. I can call EnsureChildControls() myself, but I consider that something of a hack.

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  • Any way to define getters for lazy variables in Javascript arrays?

    - by LLer
    I'm trying to add elements to an array that are lazy-evaluated. This means that the value for them will not be calculated or known until they are accessed. This is like a previous question I asked but for objects. What I ended up doing for objects was Object.prototype.lazy = function(var_name, value_function) { this.__defineGetter__(var_name, function() { var saved_value = value_function(); this.__defineGetter__(var_name, function() { return saved_value; }); return saved_value; }); } lazy('exampleField', function() { // the code that returns the value I want }); But I haven't figured out a way to do it for real Arrays. Arrays don't have setters like that. You could push a function to an array, but you'd have to call it as a function for it to return the object you really want. What I'm doing right now is I created an object that I treat as an array. Object.prototype.lazy_push = function(value_function) { if(!this.length) this.length = 0; this.lazy(this.length++, value_function); } So what I want to know is, is there a way to do this while still doing it on an array and not a fake array?

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  • Instantiate a form, then find it later, without showing it initially

    - by awilson53
    I am having a problem that is strange to me but hopefully is not so strange to someone else. : ) Some background: I am working on a simple IM client that allows the user to broadcast messages to multiple recipients. The goal is to create a chat form for each of the recipients containing the text of the broadcast message, then show that form only if the recipient responds to the broadcast-er. However, when the application receives a response then attempts to locate the form for that particular chat session (using Application.OpenForms) it cannot find it UNLESS I .Show at the time it is created. I would like to avoid having to show this form when it is created because this means that the user will see a flash on the screen. The form doesn't seem to really be created until I show it, but it would seem there has to be a way to do this without showing first. Can anyone assist? I can provide code snippets if needed, I didn't in this post because this feels more like a conceptual misunderstanding on my part than a bug in the code. Thanks in advance!

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  • Spring MVC: Where to place validation and how to validation entity references.

    - by arrages
    Let's say I have the following command bean for creating a user: public class CreateUserCommand { private String userName; private String email; private Integer occupationId; pirvate Integer countryId; } occupationId and countryId are drop down selected values on the form. They map to an entity in the database (Occupation, Country). This command object is going to be fed to a service facade like so: userServiceFacade.createUser(CreateUserCommand command); This facade will construct a user entity to be sent to the actual service. So I suppose that in the facade layer I will have to make several dao calls to map all the lookup properties of the User entity. Based on this what is the best strategy to validate that occupationId and countryId map to real entities? Where is the best place to perform this validation? There is the spring validator but I am not sure this is the best place for this, for one I am wary of this method as validation is tied to the web tier, but also that means I would need to make the dao calls in the validator for validation but I would need to call the dao's in the facade layer again when the command - entity translation occurs. Is there anything I can do better? Thanks.

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  • What happens when modifying Gemfile.lock directly?

    - by Mik378
    Since the second time of bundle install execution, dependencies are loaded from Gemfile.lock when Gemfile isn't changed. But I wonder how detection of changes is made between those two files. For instance, if I'm adding a new dependency directly into Gemfile.lock without adding it into Gemfile (as opposed to the best practice since Gemfile.lock is auto-generated from Gemfile), would a bundle install consider Gemfile as changed ? Indeed, does bundle install process compares the whole Gemfile and Gemfile.lock trees in order to detect changes? If it is, even if I'm adding a dependency directly to Gemfile.lock, Gemfile would be detected as changed (since different) and would re-erase Gemfile.lock (so losing the added dependency...) What is the process of bundle install since the launch for the second time ? To be more clear, my question is: Are changes based only from Gemfile ? That means bundler would keep a Gemfile snapshot of every bundle install execution number N and merely compares it to the bundle install execution N+1 ? Or none snapshot are created in bundler memory and bundler makes a comparison with Gemfile.lock each time to detect if Gemfile must be considered as changed.

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  • "for" loop from program 7.6 from Kochan's "Programming in Objective-C"

    - by Mr_Vlasov
    "The sigma notation is shorthand for a summation. Its use here means to add the values of 1/2^i, where i varies from 1 to n. That is, add 1/2 + 1/4 + 1/8 .... If you make the value of n large enough, the sum of this series should approach 1. Let’s experiment with different values for n to see how close we get." #import "Fraction.h" int main (int argc, char *argv[]) { NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; Fraction *aFraction = [[Fraction alloc] init]; Fraction *sum = [[Fraction alloc] init], *sum2; int i, n, pow2; [sum setTo: 0 over: 1]; // set 1st fraction to 0 NSLog (@"Enter your value for n:"); scanf ("%i", &n); pow2 = 2; for (i = 1; i <= n; ++i) { [aFraction setTo: 1 over: pow2]; sum2 = [sum add: aFraction]; [sum release]; // release previous sum sum = sum2; pow2 *= 2; } NSLog (@"After %i iterations, the sum is %g", n, [sum convertToNum]); [aFraction release]; [sum release]; [pool drain]; return 0; } Question: Why do we have to create additional variable sum2 that we are using in the "for" loop? Why do we need "release previous sum" here and then again give it a value that we just released? : sum2 = [sum add: aFraction]; [sum release]; // release previous sum sum = sum2; Is it just for the sake of avoiding memory leakage? (method "add" initializes a variable that is stored in sum2)

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  • Chat app vs REST app - use a thread in an Activity or a thread in a Service?

    - by synic
    In Virgil Dobjanschi's talk, "Developing Android REST client applications" (link here), he said a few things that took me by surprise. Including: Don't run http queries in threads spawned by your activities. Instead, communicate with a service to do them, and store the information in a ContentProvider. Use a ContentObserver to be notified of changes. Always perform long running tasks in a Service, never in your Activity. Stop your Service when you're done with it. I understand that he was talking about a REST API, but I'm trying to make it fit with some other ideas I've had for apps. One of APIs I've been using uses long-polling for their chat interface. There is a loop http queries, most of which will time out. This means that, as long as the app hasn't been killed by the OS, or the user hasn't specifically turned off the chat feature, I'll never be done with the Service, and it will stay open forever. This seems less than optimal. Long question short: For a chat application that uses long polling to simulate push and immediate response, is it still best practice to use a Service to perform the HTTP queries, and store the information in a ContentProvider?

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  • How to combine two rows and calculate the time difference between two timestamp values in MySQL?

    - by Nadar
    I have a situation that I'm sure is quite common and it's really bothering me that I can't figure out how to do it or what to search for to find a relevant example/solution. I'm relatively new to MySQL (have been using MSSQL and PostgreSQL earlier) and every approach I can think of is blocked by some feature lacking in MySQL. I have a "log" table that simply lists many different events with their timestamp (stored as datetime type). There's lots of data and columns in the table not relevant to this problem, so lets say we have a simple table like this: CREATE TABLE log ( id INT NOT NULL AUTO_INCREMENT, name VARCHAR(16), ts DATETIME NOT NULL, eventtype VARCHAR(25), PRIMARY KEY (id) ) Let's say that some rows have an eventtype = 'start' and others have an eventtype = 'stop'. What I want to do is to somehow couple each "startrow" with each "stoprow" and find the time difference between the two (and then sum the durations per each name, but that's not where the problem lies). Each "start" event should have a corresponding "stop" event occuring at some stage later then the "start" event, but because of problems/bugs/crashed with the data collector it could be that some are missing. In that case I would like to disregard the event without a "partner". That means that given the data: foo, 2010-06-10 19:45, start foo, 2010-06-10 19:47, start foo, 2010-06-10 20:13, stop ..I would like to just disregard the 19:45 start event and not just get two result rows both using the 20:13 stop event as the stop time. I've tried to join the table with itself in different ways, but the key problems for me seems to be to find a way to correctly identify the corresponding "stop" event to the "start" event for the given "name". The problem is exactly the same as you would have if you had table with employees stamping in and out of work and wanted to find out how much they actually were at work. I'm sure there must be well known solutions to this, but I can't seem to find them...

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  • Is it good practise to blank out inherited functionality that will not be used?

    - by Timo Kosig
    I'm wondering if I should change the software architecture of one of my projects. I'm developing software for a project where two sides (in fact a host and a device) use shared code. That helps because shared data, e.g. enums can be stored in one central place. I'm working with what we call a "channel" to transfer data between device and host. Each channel has to be implemented on device and host side. We have different kinds of channels, ordinary ones and special channels which transfer measurement data. My current solution has the shared code in an abstract base class. From there on code is split between the two sides. As it has turned out there are a few cases when we would have shared code but we can't share it, we have to implement it on each side. The principle of DRY (don't repeat yourself) says that you shouldn't have code twice. My thought was now to concatenate the functionality of e.g. the abstract measurement channel on the device side and the host side in an abstract class with shared code. That means though that once we create an actual class for either the device or the host side for that channel we have to hide the functionality that is used by the other side. Is this an acceptable thing to do: public abstract class MeasurementChannelAbstract { protected void MethodUsedByDeviceSide() { } protected void MethodUsedByHostSide() { } } public class DeviceMeasurementChannel : MeasurementChannelAbstract { public new void MethodUsedByDeviceSide() { base.MethodUsedByDeviceSide(); } } Now, DeviceMeasurementChannel is only using the functionality for the device side from MeasurementChannelAbstract. By declaring all methods/members of MeasurementChannelAbstract protected you have to use the new keyword to enable that functionality to be accessed from the outside. Is that acceptable or are there any pitfalls, caveats, etc. that could arise later when using the code?

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  • Full and Partial Matching of Sets

    - by jeffrey
    I have several sets of the same type [Y, M, D] and am trying to write a function to search these sets and return an array of the available sets that fit my parameters. ReturnedSets = return_matches(Y,M,D); I want the three parameters of the function return_matches to be optional. Which means any combination of values can be used to return the sets. For example, one could write - return_matches(13,null,2); - and the function would look for all sets that contain [13, anyValue, 2]; I'm writing this in PHP, to allow users to manage dated files on my website, but I'd like to be able to use this function again for other uses. Thanks! edit: (This, or variations of this, is all I can come up with so far... There is something extra that I don't understand, because this function ends up / would not work to return sets that contain y and d, but leaving m arbitrary. if(y == s[0]){ if(m == s[1]){ if(d == s[2]){ print "day match"; } } else {print "month match";} } else {print "year match";} } else {print "no match";}

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  • Conditional WHERE Clauses in SQL Server 2008

    - by user336786
    Hello, I am trying to execute a query on a table in my SQL Server 2008 database. I have a stored procedure that uses five int parameters. Currently, my parameters are defined as follows: @memberType int, @color int, @preference int, @groupNumber int, @departmentNumber int This procedure will be passed -1 or higher for each parameter. A value of -1 means that the WHERE clause should not consider that parameter in the join/clause. If the value of the parameter is greater than -1, I need to consider the value in my WHERE clause. I would prefer to NOT use an IF-ELSE statement because it seems sloppy for this case. I saw this question here. However, it did not work for me. I think the reason why is because each of the columns in my table can have a NULL value. Someone pointed this scenario out in the fifth answer. That appears to be happening to me. Is there a slick approach to my question? Or do I just need to brute force it (I hope not :(). Thank you!

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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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  • Accessing to Request object will lead to ReadEntityBody to return 0 (in a HttpHandler class)

    - by EBAG
    I created a httpHandler that successfully implements IHttpHandler for handling file uploads. It works perfectly fine. You send the file with the form, the class receives it and will save it to hard disk. It reads chunks of file with ReadEntityBody function of HttpWorkerRequest class. Here is the situation i'm faced with.If at any stage before trying to read the file with ReadEntityBody, I try to access Request object (even Request.InputStream.Length!) ReadEntityBody would return 0 means it won't read from file stream. After further testing I found out the reason behind it. Accessing to Context.Current.Request object will trigger some sort of functionality that will cause asp.net to handle file uploads at that moment by it's own! I believe this is a bug. for example exactly after this line of code, asp.net will upload the file completely, and so there will be no stream for ReadEntityBody to read from later. int FileSize = context.Request.InputStream.Length; Can anybody tell how to stop this?

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