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  • Hotkeys in webapps

    - by Johoo
    When creating webapps, is there any guidelines on which keys you can use for your own hotkeys without overriding too many of the browsers default hotkeys. For example i might want to have a custom copy command for copying entire sets of data that only makes sense for my program instead of just text. The logical combination for this would be ctrl+c but that would destroy the default copy hotkey for normal text. One solution i was thinking about is to only catch the hotkey when it "makes sense" but when you use some advanced custom selection it might be hard to differentiate if your data is focused, if text is selected or both. Right now i am only using single keys as the hotkey, so just 'c' for the example above and this seems to be what most other sites are doing too. The problem is that if you have text input this doesn't work so good. Is this the best solution? To clarify I'm talking about advanced webapps that behave more like normal programs and not just some website presenting information(even though i think these guidlines would be valid for both cases). So for the copy example it might not be a big deal if you can't copy the text in the menu but when ctrl+tab, alt+d or ctrl+e doesn't work i would be really pissed, cough flash cough.

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  • how to use a generated dbml classes to deserialize xml via linq?

    - by Eelco Meuter
    Hi, I have a complex data structure, which I boiled down in a dbml file with one class and 6 one-to-many relations. This data must also be read via xml. The xml structure is something like: <table id=1> <column 1></column 1> <column n></column n> <m-n table x> <column 1></column 1> </m-n table x> </table> where the tag <m-n table x> is one of the six related tables. The idea is to generate an xsd based upon the dbml, which I can use to create and validate a xml. This xml can hopefully deserialized into the dbml classes. The question is: Can this be done? If so, how do I generate the xsd. I use a sql server express 2008 r2 as backend. Thanks in advance for your time!

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  • Is functional GUI programming possible?

    - by eman
    I've recently caught the FP bug (trying to learn Haskell), and I've been really impressed with what I've seen so far (first-class functions, lazy evaluation, and all the other goodies). I'm no expert yet, but I've already begun to find it easier to reason "functionally" than imperatively for basic algorithms (and I'm having trouble going back where I have to). The one area where current FP seems to fall flat, however, is GUI programming. The Haskell approach seems to be to just wrap imperative GUI toolkits (such as GTK+ or wxWidgets) and to use "do" blocks to simulate an imperative style. I haven't used F#, but my understanding is that it does something similar using OOP with .NET classes. Obviously, there's a good reason for this--current GUI programming is all about IO and side effects, so purely functional programming isn't possible with most current frameworks. My question is, is it possible to have a functional approach to GUI programming? I'm having trouble imagining what this would look like in practice. Does anyone know of any frameworks, experimental or otherwise, that try this sort of thing (or even any frameworks that are designed from the ground up for a functional language)? Or is the solution to just use a hybrid approach, with OOP for the GUI parts and FP for the logic? (I'm just asking out of curiosity--I'd love to think that FP is "the future," but GUI programming seems like a pretty large hole to fill.)

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  • How do interpreters functions written in the class C++ in the main

    - by T_Geek
    Hi I'm working on a project about Data structures. In the first , I wrote everything in main but it sounds like C . But as I learned, I tried to thinkk OOP and do as little as possible in my main() methods. I've implemented some opertation in my class like add,delet,find.it's too easy to implement its . class ARB { private: struct BT { int data; BT *l; BT *r; }; struct BT *p; public ARB(); ~ARB(); void del(int n); void add(int n); }; void ARB::del(int num) { //The code ,don't care about it }; main() { // BTR T; T.add(3); T.add(5); }; But I arrived to the big program How can I define a methode which have to use a binary tree and to get a stack STACK ARB::MyFunct(BT* p) { // The code don't care about it } How can I apply it in the main programme main() { // BT T; T.add(3); T.add(5); STACK S; BT* p S=T.MyFunct(p); // error C2664 cannot convert parametre 1 }; **mention :I implement STACK class

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  • How can I convert a bunch of files from ISO-8859-1 to UTF-8 using Perl?

    - by tau
    I have several documents I need to convert from ISO-8859-1 to UTF-8 (without the BOM of course). This is the issue though. I have so many of these documents (it is actually a mix of documents, some UTF-8 and some ISO-8859-1) that I need an automated way of converting them. Unfortunately I only have ActivePerl installed and don't know much about encoding in that language. I may be able to install PHP, but I am not sure as this is not my personal computer. Just so you know, I use Scite or Notepad++, but both do not convert correctly. For example, if I open a document in Czech that contains the character "ž" and go to the "Convert to UTF-8" option in Notepad++, it incorrectly converts it to an unreadable character. There is a way I CAN convert them, but it is tedious. If I open the document with the special characters and copy the document to Windows clipboard, then paste it into a UTF-8 document and save it, it is okay. This is too tedious (opening every file and copying/pasting into a new document) for the amount of documents I have. Any ideas? Thanks!!!

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  • How to get JSON code into MYSQL database?

    - by the_boy_za
    I've created this form with a jQuery autocomplete function. The selected brand from the autocomplete list needs to get sent to a PHP file using $.ajax function. My code doesn't seem to work but i can't find the error. I don't know why the data isn't getting inserted into MYSQL database. Here is my code: JQUERY: $(document).ready(function() { $("#autocomplete").autocomplete({ minLength: 2 }); $("#autocomplete").autocomplete({ source: ["Adidas", "Airforce", "Alpha Industries", "Asics", "Bikkemberg", "Birkenstock", "Bjorn Borg", "Brunotti", "Calvin Klein", "Cars Jeans", "Chanel", "Chasin", "Diesel", "Dior", "DKNY", "Dolce & Gabbana"] }); $("#add-brand").click(function() { var merk = $("#autocomplete").val(); $("#selected-brands").append(" <a class=\"deletemerk\" href=\"#\">" + merk + "</a>"); //Add your parameters here var param = JSON.stringify({ Brand: merk }); $.ajax({ type: "POST", async: true, url: "scripttohandlejson.php", contentType: "application/json", data: param, dataType: "json", success: function (good){ //handle success alert(good) }, failure: function (bad){ //handle any errors alert(bad) } }); return false; }); }); PHP FILE: scripttohandlejson.php <?PHP $getcontent = json_decode($json, true); $getcontent->{'Brand'}; $vraag ="INSERT INTO kijken (merk) VALUES ='$getcontent' "; $voerin = mysql_query($vraag) or die("couldnt put into db"); <?

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  • PHP - "Fat Free Framework" Find Methods and Showing Results in Template

    - by user1672808
    Just started trying the "Fat Free Framework" I'm building a site using a MySQL DB with 265 fields, and 5000+ rows in the DB; I can load() a specific record easily, no problems. When using find(), afind(), and even "select()", template will show blank lines or lines with "filler" text, with the correct number of rows for the query results, but no text/data from the DB itself; Same problem whether using objects or simply arrays from result (afind() and find()). I've copied/pasted the code verbatim from examples and from documentation, with only the DB specific items changed. Still, no luck. CODE IN PHP FILE (function from CLASS): static function home() { $featured=new Axon('boats'); $F3::set('boatlist',$featured->afind('D_CustomerID=173')); F3::set('content',TEMPLATE_DIR .'/home.html'); echo Template::serve(TEMPLATE_DIR .'/layout.html'); } TEMPLATE home.html: <div class="span8"> <h3> Featured Boats </h3> <F3:repeat group="{{@boatlist}}" value="{{@boat}}"> <div style="margin-left: 2em" class="thumbnails"> <p> <a href="boat/{{@boat['D_BoatNum']}}">{{trim(@boat['D_Description'])}}</a> by {{@boat['D_CustomerID']}} </p> <p> {{@boat['D_Price']}} </p> </div> </F3:repeat> </div> The number of rows this produces coincides with the correct number of rows in the DB. However, the actual data from each field does not show. Any ideas?

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  • new Facebook Like button for Blogger

    - by David
    I want to add the new facebook like button to my blogger website. http://developers.facebook.com/docs/reference/plugins/like I have to pass the url to the blog posts in the iframe src tag. I can get the blogger posts url from <data:post.url/> but I can't put that in a src string because Bloggers template system is weird. I want to do this:<iframe allowTransparency='true' frameborder='0' scrolling='no' src='http://www.facebook.com/plugins/like.php?href=<data:post.url/>&amp;layout=standard&amp;show-faces=true&amp;width=450&amp;action=like&amp;colorscheme=light' style='border:none; overflow:hidden; width:450px; height:px'/>but blogger complains: "Your template could not be parsed as it is not well-formed. Please make sure all XML elements are closed properly. XML error message: The value of attribute "src" associated with an element type "null" must not contain the '<' character." Anybody have this working yet?

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  • Is there a Post-Build Extensible Installer System

    - by Will Hughes
    We have a product that we need to create an installer for. It has a number of components which can be installed or not as the situation demands. When we ship our installation package, we want to be able to have that include any number of additional components to be installed. For example, Foo Manager Pro contains: Foo Manager Console Foo Manager Database Foo Manager Services That might be shipped as something like: FooManagerInstaller.exe FMPConsole.pkg FMPDatabase.pkg FMPServices.pkg A package might consist of something like: Manifest Files to be deployed Additional scripts to be executed (eg find file foo.config, do some XML Manipulation) If a client wants to add custom skins and a series of plugins as part of the install, they create their own packages: FMPConsoleSkins.pkg ClientWebservices.pkg If that client then ships it to someone else who wants to add more customisation - they can do so in the same way. We can build this from scratch - but wanted to check if this sort of install system already exists. We already have a set of NAnt scripts which do something not too far from this. But they're difficult to maintain, and quite complex. They don't offer any of the 'niceties' that we'd expect from an installer (like tracking deployed files and removing them if the install fails). We've been looking a little bit at NSIS and building MSIs using WiX, but it's not clear that these can offer us the capability for downstream to provide additional packages, without inventing our own installer language.

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  • How to html encode the output of an NHaml view (or any MVC view)?

    - by jessegavin
    I have several views written in NHaml that I would like to render as encoded html. Here's one. %table.data %thead %tr %th Country Name %th ISO 2 %th ISO 3 %th ISO # %tbody - foreach(var c in ViewData.Model.Countries) %tr %td =c.Name %td =c.Alpha2 %td =c.Alpha3 %td =c.Number I know that NHaml provides syntax to Html encode the output for given lines using &=. However, in order to encode the entire view, I would essentially lose the benefit of writing my view in NHaml since it would have to look like this.... &= "<table class='data'> &= " <thead> So I was wondering if there was any cool way to be able to capture the rendered view as a string, then to html encode that string. Maybe something like the following??? public ContentResult HtmlTable(string format) { var m = new CountryViewModel(); m.Countries = _countryService.GetAll(); // Somehow render the view and store it as a string? // Not sure how to achieve this. var viewHtml = View("HtmlTable", m); // ??? return Content(viewHtml); } This question may actually have no particular relevance to the View engine that I am using I guess. Any help or thoughts would be appreciated.

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  • How to access C arrays from assembler for Windows x64?

    - by 0xdword32
    I've written an assembler function to speed up a few things for image processing (images are created with CreateDIBSection). For Win32 the assembler code works without problems, but for Win64 I get a crash as soon as I try to access my array data. I put the relevant info in a struct and my assembler function gets a pointer to this struct. The struct pointer is put into ebx/rbx and with indexing I read the data from the struct. Any idea what I am doing wrong? I use nasm together with Visual Studio 2008 and for Win64 I set "default rel". C++ code: struct myData { tUInt32 ulParam1; void* pData; }; CallMyAssemblerFunction(&myData); Assembler Code: Win32: ... push ebp; mov ebp,esp mov ebx, [ebp + 8]; pointer to our struct mov eax, [ebx]; ulParam1 mov esi, [ebx + 4]; pData, 4 byte pointer movd xmm0, [esi]; ... Win64: ... mov rbx, rcx; pointer to our struct mov eax, [rbx]; ulParam1 mov rsi, [rbx + 4]; pData, 8 byte pointer movd xmm0, [rsi]; CRASH! ...

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  • How to define Module and use it in dojo with AMD?

    - by Devdatta Tengshe
    I am maintaining and extending an old project which was pre-AMD. I wish to add an Chart to the application. for this, I have created a js file as follows: define(["dojox/charting/Chart",...."dijit/Dialog","dojo/dom-construct"], function (Chart) { function showDailyChart(data){ //code to show the chart in a dialog } return customModules.singleChart; }); I have saved this file as /customModules/singleChart.js In My main HTML Page, I have added it to the packages as follows: var dojoConfig = { parseOnLoad: true, packages: [....,{"name":"customModules", "location":location.pathname.replace(/\/[^/]+$/, "")+"/modules" } ]}; The function from which I want to call it, is pre-AMD. So I am calling it as follows: dojo.require("customModules.singleChart"); . . . customModules.singleChart.showDailyChart(data); I can see that /customModules/singleChart.js is loaded in the Firebug console as well as Net Tab. However there is no customModules.singleChart object. Strangely enough there is no error either. I have tested this in Firebug, as well as Google Chrome's developer tools. What is the correct way to call an AMD Module using dojo.require? Or is there a better way to do what I need?

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  • Method that does conditional return of method calling it?

    - by Mattias Konradsson
    Ok this might be a bit of hack but bear with me :) The background is that i'm tired of methods that that some if-statement to that messes up indention for the whole method, like: public SomeClass DoStuff(string inputStr) { SomeClass result =null; if (IsOpenFilter(inputStr)) { .... } return result; } So I was thinking , wouldn't it be neat if I could do something like this instead: public SomeClass DoStuff(string inputStr) { Require(IsOpenFilter(inputStr),null); .... return result; } The idea is that if the statement does not evaluates to true it would return null. If there wasn't a return type for the method it would simply be: Require(IsOpenFilter(inputStr)); I realize that this is kinda overlapping with code contracts but these would be more like "conditional" or "soft" contracts evaluated at runtime rather than compile time. So I guess there's two questions, can this be done somehow? I'm stumped on how to do a conditional return from calling a method. The other question is, is this a good idea? It's a bit weird to monkeypatch the language like this but I'd rather like the way the code reads. I would be even cleaner if it could be put into an attribute above the method: [Require(IsOpenFilter(inputStr))]

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  • Commit is VERY slow in my NHibernate / SQLite project

    - by Tom Bushell
    I've just started doing some real-world performance testing on my Fluent NHibernate / SQLite project, and am experiencing some serious delays when when I Commit to the database. By serious, I mean taking 20 - 30 seconds to Commit 30 K of data! This delay seems to get worse as the database grows. When the SQLite DB file is empty, commits happen almost instantly, but when it grows to 10 Meg, I see these huge delays. The database has 16 tables, averaging 10 columns each. One possible problem is that I'm storing a dozen or so IList members, but they are typically only 200 elements long. But this is a recent addition to Fluent NHibernate automapping, which stores each float in a single table row, so maybe that's a potential problem. Any suggestions on how to track this down? I suspect SQLite is the culprit, but maybe it's NHibernate? I don't have any experience with profilers, but am thinking of getting one. I'm aware of NHibernate Profiler - any recommendations for profilers that work well with SQLite? Here's the method that saves the data - it's just a SaveOrUpdate call and a Commit, if you ignore all the error handling and debug logging. public static void SaveMeasurement(object measurement) { Debug.WriteLine("\r\n---SaveMeasurement---"); // Get the application's database session var session = GetSession(); using (var transaction = session.BeginTransaction()) { try { session.SaveOrUpdate(measurement); } catch (Exception e) { throw new ApplicationException( "\r\n SaveMeasurement->SaveOrUpdate failed\r\n\r\n", e); } try { Debug.WriteLine("\r\n---Commit---"); transaction.Commit(); Debug.WriteLine("\r\n---Commit Complete---"); } catch (Exception e) { throw new ApplicationException( "\r\n SaveMeasurement->Commit failed\r\n\r\n", e); } } }

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  • asp.net ajax toolkit combobox doesn't work in hidden div

    - by sam
    I have a combobox inside a hidden div which I use css display = none to make it invisible, but when I make the div visible by setting display = block, the combobox just show the input and its button and ul list all have css as display = 'none', visibility ='hidden'. I can tell it is done by combobox inbuild javascript because I tried to use javascript to set the css manually with no luck. It is a bug of combobox. Urgent help needed. I spent a week to solve this, and our team put a lot trust on the toolkit. Please help me on this, all javascript gurus, thanks. Below is the code to reproduce the bug. When you run it, you can't see the dropdown: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebApplication1._Default" %> <%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %> <asp:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server"> </asp:ToolkitScriptManager> <div id="d" style="display:none"> <asp:ComboBox ID="ComboBox1" runat="server"> <asp:ListItem>a</asp:ListItem> <asp:ListItem>d</asp:ListItem> <asp:ListItem>f</asp:ListItem> </asp:ComboBox> <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label> </div> <div ID="Button1" runat="server" onclick="show();">click me</div> <script type="text/javascript"> function show() { var d = $get('d'); d.style.display = 'block'; } </script>

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  • Appending and prepending to XML files with Clojure

    - by Isaac Copper
    I have an XML file with format similar to: <root> <baby> <a>stuff</a> <b>stuff</b> <c>stuff</c> </baby> ... <baby> <a>stuff</a> <b>stuff</b> <c>stuff</c> </baby> </root> And a Clojure hash-map similar to: {:a "More stuff" :b "Some other stuff" :c "Yet more of that stuff"} And I'd like to prepend XML (¶) created from this hash-map after the <root> tag and before the first <baby> (¶) The XML to prepend would be like: <baby> <a>More stuff</a> <b>Some other stuff</b> <c>Yet more of that stuff</c> </baby> I'd also like to be able to delete the last one (or n...) <baby>...</baby>s from the file. I'm struggling with coming up with an idiomatic was to prepend and append this data. I can do raw string manipulations, or parse the XML using xml/parse and xml-seq and then roll through the nodes and (somehow?) replace the data there, but that seems messy. Any tips? Ideas? Hints? Pointers? They'd all be much appreciated. Thank you!

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  • Performance of Java matrix math libraries?

    - by dfrankow
    We are computing something whose runtime is bound by matrix operations. (Some details below if interested.) This experience prompted the following question: Do folk have experience with the performance of Java libraries for matrix math (e.g., multiply, inverse, etc.)? For example: JAMA: http://math.nist.gov/javanumerics/jama/ COLT: http://acs.lbl.gov/~hoschek/colt/ Apache commons math: http://commons.apache.org/math/ I searched and found nothing. Details of our speed comparison: We are using Intel FORTRAN (ifort (IFORT) 10.1 20070913). We have reimplemented it in Java (1.6) using Apache commons math 1.2 matrix ops, and it agrees to all of its digits of accuracy. (We have reasons for wanting it in Java.) (Java doubles, Fortran real*8). Fortran: 6 minutes, Java 33 minutes, same machine. jvisualm profiling shows much time spent in RealMatrixImpl.{getEntry,isValidCoordinate} (which appear to be gone in unreleased Apache commons math 2.0, but 2.0 is no faster). Fortran is using Atlas BLAS routines (dpotrf, etc.). Obviously this could depend on our code in each language, but we believe most of the time is in equivalent matrix operations. In several other computations that do not involve libraries, Java has not been much slower, and sometimes much faster.

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  • Outgoing UDP sniffer in python?

    - by twneale
    I want to figure out whether my computer is somehow causing a UDP flood that is originating from my network. So that's my underlying problem, and what follows is simply my non-network-person attempt to hypothesize a solution using python. I'm extrapolating from recipe 13.1 ("Passing Messages with Socket Datagrams") from the python cookbook (also here). Would it possible/sensible/not insane to try somehow writing an outgoing UDP proxy in python, so that outgoing packets could be logged before being sent on their merry way? If so, how would one go about it? Based on my quick research, perhaps I could start a server process listening on suspect UDP ports and log anything that gets sent, then forward it on, such as: import socket s =socket.socket(socket.AF_INET, socket.SOCK_DGRAM) s.bind(("", MYPORT)) while True: packet = dict(zip('data', 'addr'), s.recvfrom(1,024)) log.info("Recieved {data} from {addr}.".format(**packet)) But what about doing this for a large number of ports simultaneously? Impractical? Are there drawbacks or other reasons not to bother with this? Is there a better way to solve this problem (please be gentle).

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  • Storing an object to use in multiple classes

    - by Aaron Sanders
    I am wondering the best way to store an object in memory that is used in a lot of classes throughout an application. Let me set up my problem for you: We have multiple databases, 1 per customer. We also have a master table and each row is detailed information about the databases such as database name, server IP it's located and a few config settings. I have an application that loops through those multiple databases and runs some updates on them. The settings I mentioned above are updated each loop iteration into memory. The application then runs through series of processes that include multiple classes using this data. The data never changes during the processes, only during the loop iteration. The variables are related to a customer, so I have them stored in a customer class. I suppose I could make all of the members shared or should I use a singleton for the customer class? I've never actually used a singleton, only read they are good in this type of situation. Are there better solutions to this type of scenario? Also, I could have plans for this application to be multithreaded later. Sorry if this is confusing. If you have questions, let me know and I will answer them. Thanks for your help.

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  • Important question about linq to SQL performance on high loaded web applications

    - by Alex
    I started working with linq to SQL several weeks ago. I got really tired of working with SQL server directly through the SQL queries (sqldatareader, sqlcommand and all this good stuff).  After hearing about linq to SQL and mvc I quickly moved all my projects to these technologies. I expected linq to SQL work slower but it suprisongly turned out to be pretty fast, primarily because I always forgot to close my connections when using datareaders. Now I don't have to worry about it. But there's one problem that really bothers me. There's one page that's requested thousands of times a day. The system gets data in the beginning, works with it and updates it. Primarily the updates are ++ @ -- (increase and decrease values). I used to do it like this UPDATE table SET value=value+1 WHERE ID=@I'd It worked with no problems obviously. But with linq to SQL the data is taken in the beginning, moved to the class, changed and then saved. Stats.registeredusers++; Db.submitchanges(); Let's say there were 100 000 users. Linq will say "let it be 100 001" instead of "let it be increased by 1". But if there value of users has already been increased (that happens in my site all the time) then linq will be like oops, this value is already 100 001. Whatever I'll throw an exception" You can change this behavior so that it won't throw an exception but it still will not set the value to 100 002. Like I said, it happened with me all the time. The stas value was increased twice a second on average. I simply had to rewrite this chunk of code with classic ado net. So my question is how can you solve the problem with linq

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  • JavaScript on jQuery created code never gets called

    - by mare
    This is my view in ASP.NET MVC. <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Administration.Master" Inherits="System.Web.Mvc.ViewPage" %> <asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server"> </asp:Content> <asp:Content ID="Content2" ContentPlaceHolderID="HeadContent" runat="server"> <script type="text/javascript"> var ddlContentTypes; $(document).ready(function () { ddlContentTypes = $("#ContentTypes"); ddlContentTypes.bind("change", loadCreate); loadCreate(); }); function loadCreate() { var typeId = $("#ContentTypes option:selected").val(); $.get('~/' + typeId + '/Create', function (data) { $("#CreateForm").html(data); }); $("fieldset input").each(function (index, item) { $(item).attr("disabled", true); }); } </script> </asp:Content> <asp:Content ID="Content3" ContentPlaceHolderID="MainContent" runat="server"> <h2> <%=Resources.Localize.CreateWidget %></h2> <p> <% Html.RenderPartial("ContentTypeSelector"); %></p> <div id="CreateForm"> </div> </asp:Content> As you can see, it loads some HTML (actually user control) and adds it to the CreateForm div. This actually works fine. The problem is this $("fieldset input").each(function (index, item) { $(item).attr("disabled", true); }); never runs. The fieldset tag is in the response, so you don't see it here but it's there - everything is returned back fine (I checked with Firebug). Why do the above two lines of JS never run or have any effect?

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  • How to distinguish between two different UDP clients on the same IP address?

    - by Ricket
    I'm writing a UDP server, which is a first for me; I've only done a bit of TCP communications. And I'm having trouble figuring out exactly how to distinguish which user is which, since UDP deals only with packets rather than connections and I therefore cannot tell exactly who I'm communicating with. Here is pseudocode of my current server loop: DatagramPacket p; socket.receive(p); // now p contains the user's IP and port, and the data int key = getKey(p); if(key == 0) { // connection request key = makeKey(p); clients.add(key, p.ip); send(p.ip, p.port, key); // give the user his key } else { // user has a key // verify key belongs to that IP address // lookup the user's session data based on the key // react to the packet in the context of the session } When designing this, I kept in mind these points: Multiple users may exist on the same IP address, due to the presence of routers, therefore users must have a separate identification key. Packets can be spoofed, so the key should be checked against its original IP address and ignored if a different IP tries to use the key. The outbound port on the client side might change among packets. Is that third assumption correct, or can I simply assume that one user = one IP+port combination? Is this commonly done, or should I continue to create a special key like I am currently doing? I'm not completely clear on how TCP negotiates a connection so if you think I should model it off of TCP then please link me to a good tutorial or something on TCP's SYN/SYNACK/ACK mess. Also note, I do have a provision to resend a key, if an IP sends a 0 and that IP already has a pending key; I omitted it to keep the snippet simple. I understand that UDP is not guaranteed to arrive, and I plan to add reliability to the main packet handling code later as well.

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  • Throttling CPU/Memory usage of a Thread in Java?

    - by Nalandial
    I'm writing an application that will have multiple threads running, and want to throttle the CPU/memory usage of those threads. There is a similar question for C++, but I want to try and avoid using C++ and JNI if possible. I realize this might not be possible using a higher level language, but I'm curious to see if anyone has any ideas. EDIT: Added a bounty; I'd like some really good, well thought out ideas on this. EDIT 2: The situation I need this for is executing other people's code on my server. Basically it is completely arbitrary code, with the only guarantee being that there will be a main method on the class file. Currently, multiple completely disparate classes, which are loaded in at runtime, are executing concurrently as separate threads. I inherited this code (the original author is gone). The way it's written, it would be a pain to refactor to create separate processes for each class that gets executed. If that's the only good way to limit memory usage via the VM arguments, then so be it. But I'd like to know if there's a way to do it with threads. Even as a separate process, I'd like to be able to somehow limit its CPU usage, since as I mentioned earlier, several of these will be executing at once. I don't want an infinite loop to hog up all the resources. EDIT 3: An easy way to approximate object size is with java's Instrumentation classes; specifically, the getObjectSize method. Note that there is some special setup needed to use this tool.

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  • Problems with utf-8 encoding in php

    - by Addsy
    Hi, Another utf-8 related problem I believe... I am using php to update data in a mysql db then display that data elsewhere in the site. Previously I have run into utf-8 problems before where special characters are displayed as question marks when viewed in a browser but this one seems slightly different. I have a number of records to enter that contain the è character. If I enter this directly in the db then it appears correctly on the page so I take this to mean that utf-8 content is being output correctly. However when I try and update the values in the db through php, then the è character is replaced. What appears instead is & Atilde ; & uml ; (without the spaces) which appears in the browser as è I have the tables in the database set to use UTF-8. I believe this is correct cos, as mentioned, if I update the db through phpMyAdmin, its all ok. Similarly I have set the character encoding for the page which seems to be correct. I am also running the sql statement "SET NAMES 'utf8';" before trying to update the db. Anyone have any other ideas as to where the problem may lie? Many thanks

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  • Where should you put 3rd party .NET dlls when using git submodules to avoid duplication

    - by Tim Abell
    I have two .NET library projects in Visual Studio 2008 that both make use of the MySql Connector for .NET (MySql.Data.dll). These libraries are then in turn both used by a .NET command line application which also uses the Connector. The library projects are pulled in to the application's solution as git submodules and referenced by project in Visual Studio. I'm looking for the most effective strategy for storing and referencing the MySql Connector library. I have tried having the MySql.Data.dll checked in to all three projects (in their root folder), this was problematic when one project changed to a newer version of the connector dll. Although each project had its own version of the dll, only one was packaged into the resultant application leading to an API mismatch which was hard to pin down. This has put me off this approach. I have tried having the command line application reference the connector dll that is held in a submodule, however this only removes the possibility of version mismatches when there is only one submodule rather than two as in this case. I am contemplating putting the dll in the global assembly cache (GAC) of all machines that need to build or use the application, but I'm wary of not having all dependencies for an application available in source control.

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