Search Results

Search found 21023 results on 841 pages for 'computer architecture'.

Page 118/841 | < Previous Page | 114 115 116 117 118 119 120 121 122 123 124 125  | Next Page >

• kick off a map reduce job from my java/mysql webapp

  - by Brian

  Hi guys, I need a bit of archecture advice. I have a java based webapp, with a JPA based ORM backed onto a mysql relational database. Now, as part of the application I have a batch job that compares thousands of database records with each other. This job has become too time consuming and needs to be parallelized. I'm looking at using mapreduce and hadoop in order to do this. However, I'm not too sure about how to integrate this into my current architecture. I think the easiest initial solution is to find a way to push data from mysql into hadoop jobs. I have done some initial research on this and found the following relevant information and possibilities: 1) https://issues.apache.org/jira/browse/HADOOP-2536 this gives an interesting overview of some inbuilt JDBC support 2) This article http://architects.dzone.com/articles/tools-moving-sql-database describes some third party tools to move data from mysql to hadoop. To be honest I'm just starting out with learning about hbase and hadoop but I really don't know how to integrate this into my webapp. Any advice is greatly appreciated. cheers, Brian

  Read the article

• routing mvc on the web

  - by generic_noob

  Hi, I was wondering if anyone could possibly provide me some advice on how i could improve the routing (and/or architecture) to each 'section' of my application. (I'm writing in PHP5, and trying to use strict MVC) Basically, I have a generic index page for the app, and that will spew out boilerplate stuff like jquery and the css etc. and it also generates the main navidation for the entire site, but i'm unsure about the best approach to connect the 'main menu' items(hyperlinks) with their associated controllers. Up until now I have been appending strings into the url and using a 'switch' statement to branch to the correct controller(and view) by extracting the strings back out of '$GET[]' to let it execute the code for the corrosponding action. for instance if i had a basic crud system for customer data, the url to edit a customers details would look like 'www.example.com/index.php?page=customer&action=edit&id=4'. I'm worried that there is a security concern by doing it this way, and i'm not sure of an alternative to branch the main 'index.php' file to the correct controller for each action once the user has clicked the link. Would it be better to use mod_rewrite to disguise the controllers names? or to create a similar system to the ASP MVC framework, where there is a seperate routing system where each url is filtered to get the associated controller? Cheers!

  Read the article

• Best way to implement plugin framework - are DLLs the only way (C/C++ project)?

  - by Microkernel

  Introduction: I am currently developing a document classifier software in C/C++ and I will be using Naive-Bayesian model for classification. But I wanted the users to use any algorithm that they want(or I want in the future), hence I went to separate the algorithm part in the architecture as a plugin that will be attached to the main app @ app start-up. Hence any user can write his own algorithm as a plugin and use it with my app. Problem Statement: The way I am intending to develop this is to have each of the algorithms that user wants to use to be made into a DLL file and put into a specific directory. And at the start, my app will search for all the DLLs in that directory and load them. My Questions: (1) What if a malicious code is made as a DLL (and that will have same functions mandated by plugin framework) and put into my plugins directory? In that case, my app will think that its a plugin and picks it and calls its functions, so the malicious code can easily bring down my entire app down (In the worst case could make my app as a malicious code launcher!!!). (2) Is using DLLs the only way available to implement plugin design pattern? (Not only for the fear of malicious plugin, but its a generic question out of curiosity :) ) (3) I think a lot of softwares are written with plugin model for extendability, if so, how do they defend against such attacks? (4) In general what do you think about my decision to use plugin model for extendability (do you think I should look at any other alternatives?) Thank you -MicroKernel :)

  Read the article

• what patern is layerd architechture in asp.net ?

  - by haansi

  Hi, I am a asp.net developer and don't know much about patterns and architecture. I will very thankful if you can please guide me here. In my web applications I use 4 layers. Web site project (having web forms + code behind cs files, user controls + code behind cs files, master pages + code behind cs files) CustomTypesLayer a class library (having custom types, enumerations, DTOs, constructers, get, set and validations) BusinessLogicLayer a class library (having all business logic, rules and all calls to DAL functions) DataAccessLayer a class library( having just classes communicating to database.) -My user interface just calls BusinessLogicLayer. BusinessLogicLayer do proecessign in it self and for data it calls DataAccessLayer funtions. -Web forms do not calls directly DAL. -CustomTypesLayer is shared by all layers. Please guide me is this approach a pattern ? I though it may be MVC or MVP but pages have there code behind files as well which are confusing me. If it is no patren is it near to some patren ? pleaes guide thanks

  Read the article

• 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?

  Read the article

• Abstract Design Pattern implementation

  - by Pathachiever11

  I started learning design patterns a while ago (only covered facade and abstract so far, but am enjoying it). I'm looking to apply the Abstract pattern to a problem I have. The problem is: Supporting various Database systems using one abstract class and a set of methods and properties, which then the underlying concrete classes (inheriting from abstract class) would be implementing. I have created a DatabaseWrapper abstract class and have create SqlClientData and MSAccessData concrete class that inherit from the DatabaseWrapper. However, I'm still a bit confused about how the pattern goes as far as implementing these classes on the Client. Would I do the following?: DatabaseWrapper sqlClient = new SqlClientData(connectionString); This is what I saw in an example, but that is not what I'm looking for because I want to encapsulate the concrete classes; I only want the Client to use the abstract class. This is so I can support for more database systems in the future with minimal changes to the Client, and creating a new concrete class for the implementations. I'm still learning, so there might be a lot of things wrong here. Please tell me how I can encapsulate all the concrete classes, and if there is anything wrong with my approach. Many Thanks! PS: I'm very excited to get into software architecture, but still am a beginner, so take it easy on me. :)

  Read the article

• How to structure Javascript programs in complex web applications?

  - by mixedpickles

  Hi there. I have a problem, which is not easily described. I'm writing a web application that makes heavy usage of jquery and ajax calls. Now I don't have experience in designing the architecture for javascript programms, but I realize that my program has not a good structure. I think I have to many identifiers referring to the same (at least more or less) thing. Let's have an exemplary look at an arbitrary UI widget: The eventhandlers use DOM elements as parameters. The DOM element represents a widget in the browser. A lot of times I use jQuery objects (I think they are basically a wrapper around DOM elements) to do something with the widget. Sometimes they are used transiently, sometimes they are stored in a variable for later purposes. The ajax function calls use strings identifiers for these widgets. They are processed server side. Beside that I have a widget class whose instances represents a widget. It is instantiated through the new operator. Now I have somehow four different object identifiers for the same thing, which needs to be kept in sync until the page is loaded anew. This seems not to be a good thing. Any advice?

  Read the article

• How to use multiple SkyDrive accounts on one computer?

  - by user1563721

  Is there any way how to use multiple SkyDrive accounts on one computer running MAC OS X or Windows 8? I would like to sync data from different accounts to different folder and not to merge these accounts to one. The reason is that every SkyDrive has it's storage limits and I'm using every account for different work data. The result should be the following: I have a number of SkyDrive accounts every for different work, let's say: S1 S2 S3 I would like to sync exactly the same number of folders on computer using different accounts to sync them: SkyDriveS1Folder - (folder on computer which syncing the content of S1 SkyDrive) SkyDriveS2Folder - (folder on computer which syncing the content of S2 SkyDrive) SkyDriveS3Folder - (folder on computer which syncing the content of S3 SkyDrive) Is it possible somehow? I found a workaround for Windows machines (http://superuser.com/questions/525932/running-multiple-instances-of-microsoft-skydrive) but is there anything for MAC OS X machines? Or is it possible through any third party application?

  Read the article

• Win7 Prof. Computer won't wake on lan via Magic Packet from outside network

  - by Michael

  Hi all. I just purchased a new computer running Windows 7 Professional x64. I'd like to save power by having it sleep after an hour, but I would also like to be able to Remote Desktop into it at my leisure. I set up a static IP and have port forwarding set up on the router. If the computer is awake, the RDP connection works just fine. I downloaded and installed Wake-On-Lan thanks to this article If I put my new computer to sleep and send the magic packet from my old computer inside of my home network it wakes up. If I do the same thing, however, from my work computer outside the network it does not. I figured the Firewall was blocking the incoming traffic, but nothing in the Windows Firewall logs points to this happening. I'm wondering if anyone has any suggestions or any tests I can run through in order to narrow down what the problem might be. Thanks in advance for any help you might be able to offer.

  Read the article

• Transfer hard-drive with windows XP to another computer. On booting, asks to activate xp

  - by Jesse

  I had an old computer sitting around that I have not been able to boot successfully. I moved the hard drive and placed it in my newer computer. If I boot linux, I can mount the XP hard-drive and access the files. If I try to boot from the XP hard-drive, it will boot, but it asks me to activate windows before proceeding. If I continue, I get the "activation window" with two images/icons(?) which are failing to load. Nothing else happens. The version of windows came with the original computer the hard-drive came from, so I'm not sure if I'm married to the broken computer (I hope not!). Is there anything I can do in order to boot into XP from the new computer?

  Read the article

• Why am I unable to access the network shares on my own computer?

  - by DoomStone

  I am having some problems with media center computer, with Windows 7 on it. The computers IP address is 192.168.1.13, and another computer can without any problem navigate to \\192.168.1.13, but the computer itself can not. Neither \\servername nor \\localhost. If I reboot the computer a couple of times, it will work again, but this is a big problem as my computer cleans my media center library on boot and there, if it can not access \\192.168.1.13, it will think that all the files have been removed and therefore delete them from the database. I really have no idea on where to start with this problem, but if anyone has tried this before and fixed it, I would be very happy, as it would save me from having to reinstall the whole system.

  Read the article

• Automatically make user local administrator on their computer through GPO?

  - by Grant

  In our AD 2003 domain each user gets local admin permissions on their computer. Everyone else can login with their domain account as normal user. Right now this means going to the desktop and manually adding the user as a local administrator. Is there any way to automate this process through logon scripts or GPOs? I have found ways to use a gpo to make everyone who logs in to a computer a local admin, but really only want to give it to the primary user (or in some cases users) of the computer. I've also seen methods that required adding a group for each computer...but really dont want to clutter AD like that. I do have a list mapping each user to each computer name. If it matters the desktops are a mix of xp and win7.

  Read the article

• Converting EBNF to BNF

  - by Vivin Paliath

  It's been a few years since my computer-language class and so I've forgotten the finer points of BNF's and EBNF's and I don't have a textbook next to me. Specifically, I've forgotten how to convert an EBNF into BNF. From what little I remember, I know that one of the main points is to convert { term } into <term> | <many-terms>. But I don't remember the other rules. I've tried to look this up online but I can only find links to either homework questions, or a small comment about converting terms with curly braces. I can't find an exhaustive list of rules that define the translation.

  Read the article

• Port scientific software to GPU and publish it

  - by Werner

  Hi, let's say that I am a physicist and that I am the master of the universe when it comes to port salready existing oftware to GPU's with 100x or more speedups. Let's say that I find that some other scientist, which does not know how to program GPU, publishes the Open Source code in his/her website of a physical simulation program, in the field I am expert on. Let's say that I realize "I can port that code to GPU", and I suggest him, but he shows no interest. My interest here is, 1) to port it to GPU, 2) to publish this result in a scientific journal related with physics and/or computer science My question for you is 1- would you proceed here to port the code to GPU (or other new arch) and publish it? 2- how would you do it and which journal do you suggest? Thanks

  Read the article

• OpenCV - DLL missing, but it's not?

  - by charles-22

  I am trying just a basic program with OpenCV with the following code: #include "cv.h" #include "highgui.h" int main() { IplImage* newImg; newImg = cvLoadImage("~/apple.bmp", 1); cvNamedWindow("Window", 1); cvShowImage("Window", newImg); cvWaitKey(0); cvDestroyWindow("Window"); cvReleaseImage(&newImg); return 0; } When I run this, I get The program can't start because libcxcore200.dll is missing from your computer. Try reinstalling the program to fix this problem. However, I can see this DLL. It exists. I have added the following to the input dependencies for my linker C:\OpenCV2.0\lib\libcv200.dll.a C:\OpenCV2.0\lib\libcvaux200.dll.a C:\OpenCV2.0\lib\libcxcore200.dll.a C:\OpenCV2.0\lib\libhighgui200.dll.a What gives? I'm using visual studio 2008.

  Read the article

• What are the CS fundamentals behind package/dependency management?

  - by Frep D-Oronge

  Often I hear about situations where companies are developing extensable in house software (the dreaded enterprise 'framework') which is supposed to support multiple 'plugins' from diffirent teams. Usually this ends up being a half baked solution that does not really work due to compatibility prolems between addins, or between addins and the framework itself. Usually this means QA have to 'rubber stamp' a global set of versions accross all plugins, or more usually plugins are released and stuff breaks in nasty ways. This problem has been solved before however, for example the package management systems like apt for debian linux. I suspect that the reason it works is that it is built from the start on a known 'Computer Science-y' concept. My question is what is it?

  Read the article

• Static Evaluation Function for Checkers

  - by Kamikaze

  Hi all! I'm trying to write an evaluation function for a game of checkers that I'm developing but I can't find the right documentation. I've read several documents on the web witch describe different techniques for either writing one or letting the computer find it(using genetic algorithms or Bayesian learning) but they're too complicated for a novice like me. All documents pointed a reference to "Some studies in machine learning using the game of checkers" by A.L.Samuel but I couldn't get my hands on it yet :(. I've only read the follow up "Some studies in machine learning using the game of checkers -II" and found some good info there, but it doesn't explain what the eval parameters mean (I think I don't have the whole article). Thanks for your help!

  Read the article

• Should we write detailed architecture design or just an outline when designing a program?

  - by EpsilonVector

  When I'm doing design for a task, I keep fighting this nagging feeling that aside from being a general outline it's going to be more or less ignored in the end. I'll give you an example: I was writing a frontend for a device that has read/write operations. It made perfect sense in the class diagram to give it a read and a write function. Yet when it came down to actually writing them I realized they were literally the same function with just one line of code changed (read vs write function call), so to avoid code duplication I ended up implementing a do_io function with a parameter that distinguishes between operations. Goodbye original design. This is not a terribly disruptive change, but it happens often and can happen in more critical parts of the program as well, so I can't help but wondering if there's a point to design more detail than a general outline, at least when it comes to the program's architecture (obviously when you are specifying an API you have to spell everything out). This might be just the result of my inexperience in doing design, but on the other hand we have agile methodologies which sort of say "we give up on planning far ahead, everything is going to change in a few days anyway", which is often how I feel. So, how exactly should I "use" design?

  Read the article

• Voting software with remote units - architectural questions

  - by David Neale

  I'm looking at designing some software that registers live votes (let's say A,B,C or D). The vote needs to be picked up and processed by a .NET engine. The remote voting units should be as small as possible. What form of data transmission should be used for the voting? The data is obviously very simple but there is a need to make sure each unit can only vote once per question. How would the data be received by the computer running the software?

  Read the article

• Error message when running "make" command: /usr/bin/ld: i386 architecture of input file is incompatible with i386:x86-64 output

  - by user784637

  I am unable to create a working executable file by running the make command in a tree previously built on an i386 machine. I'm getting an error message in the form of me@me-desktop:~$ make /usr/bin/ld: i386 architecture of input file `../.. /Lib/libProgram.a(something.o)' is incompatible with i386:x86-64 output I've been told and reassured that this program has been tested and successfully compiled on 64-bit Fedora. I'm running a 64-bit machine me@me-desktop:~$ uname -m x86_64 I'm running Ubuntu 10.04 me@me-desktop:~$ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 10.04.3 LTS Release: 10.04 Codename: lucid I'm using g++ # me@me-desktop:~$ g++ --version g++ (Ubuntu 4.4.3-4ubuntu5) 4.4.3 Copyright (C) 2009 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. I'm also using libtool # me@me-desktop:~$ libtool --version ltmain.sh (GNU libtool) 2.2.6b Written by Gordon Matzigkeit <[email protected]>, 1996 Any clues as to what is going wrong?

  Read the article

• Is a Mission Oriented Architecture (MOA) a better way to describe things than SOA?

  - by Brian Langbecker

  I might sound like a troll, but I would like to seriously understand this deeper. The place I work at has started to use the term MOA, versus SOA as we believe it drives more clarity and want to compare it to the true goals of SOA. A Mission Oriented Architecture is an approach whereby an application is broken down into various business mission elements, with the database, file assets, batch and real time functionality all tightly coupled in terms of delivering that piece of the functionality. The mission allows the developers to focus on a specific piece of functionality to get it right, and to build it with the ability for that piece to scale as an independent entity within the overall application. By tightly coupling the data, file assets and business logic you achieve the goals of working on a very large problem in bite size pieces. Some definitions of SOA mix it up with what is essentially a method call on a web service versus a true "service". As an architect, I have always found it fun getting everyone on the same page regarding SOA. Is it better to call it a "mission" versus a "service"?

  Read the article

• Assuming "clean code/architecture" is there a difference in "effort" between PHP or Java/J2EE web application development?

  - by PhD

  A client asked us to estimate effort when selecting PHP as the implementation language for his next web-based application. We spent about a week exploring PHP, prototyping, testing etc., We are quite new to this language - may have hacked around it in the past but, let's go with PHP-noobs but application development experts (for the lack of a better, less flattering word :) It seems, that if we write, clean maintainable code, follow separation of concerns, enterprise architecture patters (DAOs etc.) the 'effort' in creating an object-oriented PHP based web-application seems to be the same for a Java based one. Here's our equation for estimating the effort (development/delivery time): ConstructionEffort = f(analysis, design, coding, testing, review, deployment) We were specifically comparing effort estimates in creating an enterprise application with the following: PHP + CakePHP/CodeIgniter (should we have considered others?) Java + Spring + Restlet It's an end-to-end application: Client: Javascript/jQuery + HTML/CSS Middle tier/Business Logic - (Still evaluating PHP/Java) Database: MySQL The effort estimates of the 1st and 3rd tier are constant and relatively independent of the middle tier's technology. At a high level with an initial breakdown into user stories of the requested features as well as a high-level SWAG on the sheer number of classes/SLOC that would be required for PHP doesn't seem to differ by much from what is required of the same in Java. Is this correct? We are basing our initial estimates on the initial prototyping/coding we've done with PHP - we are currently disregarding fluency with the language as a factor, since that'll be an initial hurdle and not a long term impediment IMHO (we also have sufficient time to become quite fluent with PHP). I'm interested in knowing the programmers' perspective with respect to effort when creating similar applications with either of the languages to justify choosing one over the other. Are we missing something here? It seems we are going against popular belief of PHP being quicker to market (or we being very fluent with Java have our vision clouded). It doesn't seem to have any coding/programming effort saving from what we/ve played around with.

  Read the article

• How to remove all associated files and configuration settings of an app installed through 'force architecture' command

  - by Mysterio

  A few weeks ago I installed a 32 bit .deb file through the 'force architecture' command (on my 64bit notebook), however the procedure was unsuccessful and I used the apt-get purgecommand to uninstall the app. It seems there are some leftovers of the app I uninstalled which has now broken system update. Synaptic recommended a sudo apt-get install -fwhich I did in the terminal with this initial response: Reading package lists... Done Building dependency tree Reading state information... Done The following package was automatically installed and is no longer required: libntfs10 Use 'apt-get autoremove' to remove them. The following packages will be REMOVED: crossplatformui 0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded. 1 not fully installed or removed. After this operation, 0 B of additional disk space will be used. Do you want to continue [Y/n]? I chose 'Y' then got this response: (Reading database ... 187616 files and directories currently installed.) Removing crossplatformui ... ztemtvcdromd: no process found dpkg: error processing crossplatformui (--remove): subprocess installed post-removal script returned error exit status 1 Errors were encountered while processing: crossplatformui E: Sub-process /usr/bin/dpkg returned an error code (1) It seems the app I installed crossplatformuiis still on my system and has caused update manager to stop running with a partial upgrade warning. What do I do now?

  Read the article

• Is the Entity Component System architecture object oriented by definition?

  - by tieTYT

  Is the Entity Component System architecture object oriented, by definition? It seems more procedural or functional to me. My opinion is that it doesn't prevent you from implementing it in an OO language, but it would not be idiomatic to do so in a staunchly OO way. It seems like ECS separates data (E & C) from behavior (S). As evidence: The idea is to have no game methods embedded in the entity. And: The component consists of a minimal set of data needed for a specific purpose Systems are single purpose functions that take a set of entities which have a specific component I think this is not object oriented because a big part of being object oriented is combining your data and behavior together. As evidence: In contrast, the object-oriented approach encourages the programmer to place data where it is not directly accessible by the rest of the program. Instead, the data is accessed by calling specially written functions, commonly called methods, which are bundled in with the data. ECS, on the other hand, seems to be all about separating your data from your behavior.

  Read the article

• Write the longest possible loop.

  - by Abhay

  Hello Group, Recently I was asked this question in a technical discussion. What is the longest possible loop that can be written in a programming language? This loop has to be as long as possible and yet not an infinite loop and should not end-up crashing the program (Recursion etc...) I honestly did not know how to attack this problem, so I asked him if is it practically possible. He said using some computer science concepts, you can arrive at a hypothetical number which may not be practical but nevertheless it will still not be infinite. Anyone here; knows how to analyse / attack this problem. P.S. Choosing some highest limit for a type that can store the highest numerical value is apparently not an answer. Thanks in advance,

  Read the article

< Previous Page | 114 115 116 117 118 119 120 121 122 123 124 125  | Next Page >