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  • What shall I include in a 10 week web technologies course?

    - by Iain
    In September I will be teaching a university module on web technologies. This session will be available to 1st year (freshman) students who don't necessarily have any programming knowledge or know how the web works. In the 2nd semester I will be teaching Flash, which is my specialism, so I know exactly what I am going to teach, but in the 1st semester I will be teaching them web standards technologies - HTML, CSS, JS, jQuery, PHP and MySQL. Where I need advice is how to proportion the emphasis for each part, and which parts of each technology to cover. Another real issue I'm struggling with is how much of the bad old ways should I teach them? Do they need to know about bold as well as strong, etc. UPDATE: based, on your feedback I will only be teaching the latest version of everything - CSS3, HTML5 etc. I'm not sure exactly how long the semester will be but I'm guessing about 10-12 weeks. Each session is a 2 hour lab. Obviously there's only so much I can cover in that time and it will be up to the students to go a research this stuff properly on W3 schools etc. My ideas so far were: Lesson 0 - Course intro and overview of the current tech landscape. What is out there, what will we be learning, what won't we. What is a web server, URL etc. Looking at different example websites and discussing how they work. Lesson 1 - HTML basics (head, body, title, img, table, a, lists, h1, strong etc) Lesson 2 - CSS for styling and layout - fonts, webfonts, float etc Lesson 3 - Intro to programming JS (variables, loops, conditionals, functions) Lesson 4 - more JS programming fundamentals, DOM manipulation Lesson 5 - jQuery - making things fly about and look cool Lesson 6 - XML and Ajax Lesson 7 - PHP basics - syntax, server-side principles Lesson 8 - PHP and MySQL - forms, logins, saving user info Lesson 9 - don't know Lesson 10 - don't know Please let me know if you think this is the right order, what have I missed, how to use any spare sessions etc. Thanks :) UPDATE BASED ON RESPONSES: Thanks for all your responses - some great stuff. To be absolutely clear, this is not a computer science course, it is a practical module on a creative technology course. The emphasis definitely has to be on making cool things work rather than understanding how the backbone of the internet works. That can come later, if the students are interested. At the end of the module I would like the students to be able to produce a web page or pages that does something cool, using some or all of the technologies I cover. Many of these topics are of course far beyond the scope of a 2 hour session, however I do not have the option of reducing the syllabus, I will just have to explain what the technology does and encourage the student to research it in their own time.

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  • Best way to remote restart Ubuntu from Windows machine

    - by robsoft
    Background: I'm looking to put a series of Ubuntu machines into retail locations, they're being used as dumb kiosks to show a series of slides onto large LCD panel TV screens. Once installed, they won't have a keyboard or mouse connected but will have a fixed IP on the local network. Everything is configured to auto-start, no automatic updates, no power saving etc - I think we're pretty-much good to go apart from one thing. I need the retail staff to be able to restart the boxes if a problem arises. We have VNC running (now that we've turned off desktop enhancements!) so that we can remotely get into the machines if we need to, but that's not something we would allow the retail staff to do. The machines are going to be physically 'out of the way' (probably in the ceiling space) so the power button is not easily accessible!. I'd like to have some means of allowing the retail staff to restart the Ubuntu machine, from the desktop of one of their Windows terminals. I don't really want to give them some kind of raw terminal access (the command line will frighten them!) and I don't want them to use VNC (as stated above). Ideally there would be an icon on the Windows desktop, they double-click it, reply to a simple 'are you sure?' prompt, and then the Ubuntu box is told to restart. The Windows side of that won't be a problem, we can write something using Delphi, Python & Qt4, whatever - it's the Ubuntu side of it I'm stuck with. Out of sight/view, could I have a Windows program open a terminal across the network and tell Ubuntu to restart? Is this what SSH could be used for (I have never set that kind of thing up). The Windows programming side isn't really an issue, it's just that I'm a total Ubuntu noob and don't know where to start from the platform point of view. The other thing we considered is also having the machine automatically restart itself at a set time each day (obviously out of store hours!). To me, that seems a bit unnecessary (though forcing a restart once a week/month might be worthwhile). Any thoughts or suggestions? Being able to restart the box on demand across the network is my prime requirement.

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  • How can I get my ATI / AMD drivers to work with any kernel above 3.2.0.x?

    - by TorakTu
    How can I get my ATI / AMD drivers to work with any kernel above 3.2.0.x ? WHAT DID WORK Installed original AMD64 version of Ubuntu 12.04 ISO image. Burned DVD and installed which shown kernel 3.2.0-23 to begin with. Got 5.1 surround sound working. Got ATI ( Now its AMD ) video drivers installed for my Radeon HD R6870 Video card from AMD's website. fglrxinfo came up and reported as normal. THE PROBLEM Kernel 3.2.0.x kept locking up so I tried higher kernel versions. But ATI / AMD Drivers do not install on any kernel Above 3.2.0.x WHAT I HAVE TRIED I have gone over this tutorial many times ( https://help.ubuntu.com/community/BinaryDriverHowto/ATI ) and it doesn't work on ANY kernel except 3.2.0.x. The problems I am having here are that the ATI / AMD drivers working for the 12.04 Precise with kernel 3.2.0-23 and 24, But the computer kept locking up. Although all my games would work, the lock ups were random and were constant. So I looked all over the web for 3 days trying to find an answer and the lock up issue was said to just update the kernel. So I did. Have tried many kernels. All of them .. no lock ups. BUT the Restricted AMD drivers from the AMD website will not install. And none of the OpenSource AMD drivers have EVER installed no matter what Kernel or version I tried. EXAMPLE OUTPUT OF 3D TYPE OF ERRORS Javax.media.opengl.GLException: glXGetConfig failed: error code GLX_NO_EXTENSION at com.sun.opengl.impl.x11.X11GLDrawableFactory.glXGetConfig(X11GLDrawableFactory.java:651) at com.sun.opengl.impl.x11.X11GLDrawableFactory.xvi2GLCapabilities(X11GLDrawableFactory.java:350) at com.sun.opengl.impl.x11.X11GLDrawableFactory.chooseGraphicsConfiguration(X11GLDrawableFactory.java:174) at javax.media.opengl.GLCanvas.chooseGraphicsConfiguration(GLCanvas.java:520) at javax.media.opengl.GLCanvas.<init>(GLCanvas.java:131) at haven.HavenPanel.<init>(HavenPanel.java:68) at haven.HavenPanel.<init>(HavenPanel.java:78) at haven.MainFrame.<init>(MainFrame.java:182) at haven.MainFrame.main2(MainFrame.java:306) at haven.MainFrame.access$100(MainFrame.java:34) at haven.MainFrame$7.run(MainFrame.java:360) at java.lang.Thread.run(Thread.java:722) And of course this is what fglrxinfo shows : X Error of failed request: BadRequest (invalid request code or no such operation) Major opcode of failed request: 139 (ATIFGLEXTENSION) Minor opcode of failed request: 66 () Serial number of failed request: 13 Current serial number in output stream: 13 EDIT : I forgot to mention that I DID look at this post over the last few days and it did not help.

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  • Contract / Project / Line-Item hierarchy design considerations

    - by Ryan
    We currently have an application that allows users to create a Contract. A contract can have 1 or more Project. A project can have 0 or more sub-projects (which can have their own sub-projects, and so on) as well as 1 or more Line. Lines can have any number of sub-lines (which can have their own sub-lines, and so on). Currently, our design contains circular references, and I'd like to get away from that. Currently, it looks a bit like this: public class Contract { public List<Project> Projects { get; set; } } public class Project { public Contract OwningContract { get; set; } public Project ParentProject { get; set; } public List<Project> SubProjects { get; set; } public List<Line> Lines { get; set; } } public class Line { public Project OwningProject { get; set; } public List ParentLine { get; set; } public List<Line> SubLines { get; set; } } We're using the M-V-VM "pattern" and use these Models (and their associated view models) to populate a large "edit" screen where users can modify their contracts and the properties on all of the objects. Where things start to get confusing for me is when we add, for example, a Cost property to the Line. The issue is reflecting at the highest level (the contract) changes made to the lowest level. Looking for some thoughts as to how to change this design to remove the circular references. One thought I had was that the contract would have a Dictionary<Guid, Project> which would contain ALL projects (regardless of their level in hierarchy). The Project would then have a Guid property called "Parent" which could be used to search the contract's dictionary for the parent object. THe same logic could be applied at the Line level. Thanks! Any help is appreciated.

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  • Methodology to understanding JQuery plugin & API's developed by third parties

    - by Taoist
    I have a question about third party created JQuery plug ins and API's and the methodology for understanding them. Recently I downloaded the JQuery Masonry/Infinite scroll plug in and I couldn't figure out how to configure it based on the instructions. So I downloaded a fully developed demo, then manually deleted everything that wouldn't break the functionality. The code that was left allowed me to understand the plug in much greater detail than the documentation. I'm now having a similar issue with a plug in called JQuery knob. http://anthonyterrien.com/knob/ If you look at the JQuery Knob readme file it says this is working code: $(function() { $('.dial') .trigger( 'configure', { "min":10, "max":40, "fgColor":"#FF0000", "skin":"tron", "cursor":true } ); }); But as far as I can tell it isn't at all. The read me also says the Plug in uses Canvas. I am wondering if I am suppose to wrap this code in a canvas context or if this functionality is already part of the plug in. I know this kind of "question" might not fit in here but I'm a bit confused on the assumptions around reading these kinds of documentation and thought I would post the query regardless. Curious to see if this is due to my "newbi" programming experience or if this is something seasoned coders also fight with. Thank you. Edit In response to Tyanna's reply. I modified the code and it still doesn't work. I posted it below. I made sure that I checked the Google Console to insure the basics were taken care of, such as not getting a read-error on the library. <!DOCTYPE html> <meta charset="UTF-8"> <title>knob</title> <link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/themes/hot-sneaks/jquery-ui.css" type="text/css" /> <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.js" charset="utf-8"></script> <script src="https://ajax.googleapis.com/ajax/libs/jqueryui/1.8.21/jquery-ui.min.js"></script> <script src="js/jquery.knob.js"></script> <div id="button1">test </div> <script> $(function() { $("#button1").click(function () { $('.dial').trigger( 'configure', { "min":10, "max":40, "fgColor":"#FF0000", "skin":"tron", "cursor":true } ); }); }); </script>

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  • Ubuntu 10.10 not recognizing external hard drive

    - by sr71
    Installed Ubuntu 10.10 on a hard drive by itself (no windows). All updates are up to date. Everything`works fine except when I plug in a 320 gig Toshiba external hard drive....it is not recognized. When I plug in an 8 gig flash drive it is recognized no problem. What do I mean by "not recognized"? I mean: how do you know it was not recognized. You can check the command "cat /proc/partitions" in a terminal with and without the hdd attached. If you see some difference, it's ok. If the difference is something like "sda1" (sd+letter+number) then you have partition on it, maybe it can't be handled in Ubuntu (no filesystem on it or so). If there is only "sda" in the difference for example (sd+letter, but no number after it) then the drive itself is detected, just no partition is created on it. Also you can check out the messages of the kernel, with the "dmesg" command in the terminal. If there is no disk/partition/anything in /proc/partitions, there can be an USB level problem, you can issue command "lsusb" as it was suggested before my answer. It's really matter of what do you mean about "not recognized". @Marco Ceppi @Oli @Pitto By "not recognized" I meant that when I plug in a 8 gig flash drive an icon immediately appears on the desktop imdicating that there is a flash drive plugged in and I can click on it and view the files on the flash drive. It also shows up on the "Nautilus" default file manager. When I plug in the 320 gig Toshiba external hard drive, I get no indication on the desktop or the file manager (thus "not recogized"). When I run the command "cat/proc/partitions/" I get an error message Could not open location 'file:///home/bob/cat/proc/partitions' with or without the external hard drive installed. With the "dmeg" command I get about 10 pages of info with no mention of disk/partition/anything in /proc/partitions. When I run "lsub" command I get the following: bob@bob-desktop:~$ lsusb Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 003: ID 04b3:3003 IBM Corp. Rapid Access III Keyboard Bus 003 Device 002: ID 04b3:3004 IBM Corp. Media Access Pro Keyboard Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub bob@bob-desktop:~$

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  • Why does the login screen fail to appear?

    - by a different ben
    My system: Dell Precision T3500 nVidia Quadro NVS 295 Ubuntu 12.04 x86_64 (3.2.0-32) Essential problem: On boot my system won't get past the splash screen. I can switch to another virtual terminal and log in, I can also ssh from another system -- so it appears that the problem might be with the display manager. How can I diagnose and fix this problem? More info: From a VT I can issue sudo lightdm restart, and this will bring up the login screen and and I can continue from there. So I do have access to my system. Update-manager recently updated a number of packages, including a bunch of x11 and xorg packages, some nVidia drivers, rpcbind, etc etc. My boot log (if that is any guidance) says the following: fsck from util-linux 2.20.1 fsck from util-linux 2.20.1 fsck from util-linux 2.20.1 fsck from util-linux 2.20.1 rpcbind: Cannot open '/run/rpcbind/rpcbind.xdr' file for reading, errno 2 (No such file or directory) rpcbind: Cannot open '/run/rpcbind/portmap.xdr' file for reading, errno 2 (No such file or directory) /dev/sda1: clean, 597650/1525920 files, 3963433/6103296 blocks /dev/sda7: clean, 11/6406144 files, 450097/25608703 blocks /dev/sda5: clean, 158323/1525920 files, 1886918/6103296 blocks /dev/sda8: clean, 250089/107929600 files, 111088810/431689728 blocks Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd * Starting AppArmor profiles [80G [74G[ OK ] Loading the saved-state of the serial devices... /dev/ttyS0 at 0x03f8 (irq = 4) is a 16550A * Starting ClamAV virus database updater freshclam [80G [74G[ OK ] * Starting Name Service Cache Daemon nscd [80G [74G[ OK ] * Starting modem connection manager[74G[ OK ] * Starting K Display Manager[74G[ OK ] * Starting mDNS/DNS-SD daemon[74G[ OK ] * Stopping GNOME Display Manager[74G[ OK ] * Stopping K Display Manager[74G[ OK ] * Starting bluetooth daemon[74G[ OK ] * Starting network connection manager[74G[ OK ] * Starting Postfix Mail Transport Agent postfix [80G [74G[ OK ] speech-dispatcher disabled; edit /etc/default/speech-dispatcher * Starting VirtualBox kernel modules [80G [74G[ OK ] * Starting the Winbind daemon winbind [80G [74G[ OK ] saned disabled; edit /etc/default/saned * Starting anac(h)ronistic cron[74G[ OK ] * Stopping anac(h)ronistic cron[74G[ OK ] * Checking battery state... [80G [74G[ OK ] nxsensor is disabled in '/usr/NX/etc/node.cfg' Trying to start NX server: NX 122 Service started. NX 999 Bye. Trying to start NX statistics: NX 723 Cannot start NX statistics: NX 709 NX statistics are disabled for this server. NX 999 Bye. * Stopping System V runlevel compatibility[74G[ OK ] * Starting Mount network filesystems[74G[ OK ] * Stopping Mount network filesystems[74G[ OK ] * Stopping regular background program processing daemon[74G[ OK ] * Starting regular background program processing daemon[74G[ OK ] * Starting anac(h)ronistic cron[74G[ OK ] * Stopping anac(h)ronistic cron[74G[ OK ]

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  • Self-Executing Anonymous Function vs Prototype

    - by Robotsushi
    In Javascript there are a few clearly prominent techniques for create and manage classes/namespaces in javascript. I am curious what situations warrant using one technique vs. the other. I want to pick one and stick with it moving forward. I write enterprise code that is maintained and shared across multiple teams, and I want to know what is the best practice when writing maintainable javascript ? I tend to prefer Self-Executing Anonymous Functions however I am curious what the community vote is on these techniques. Prototype : function obj() { } obj.prototype.test = function() { alert('Hello?'); }; var obj2 = new obj(); obj2.test(); Self-Closing Anonymous Function : //Self-Executing Anonymous Function (function( skillet, $, undefined ) { //Private Property var isHot = true; //Public Property skillet.ingredient = "Bacon Strips"; //Public Method skillet.fry = function() { var oliveOil; addItem( "\t\n Butter \n\t" ); addItem( oliveOil ); console.log( "Frying " + skillet.ingredient ); }; //Private Method function addItem( item ) { if ( item !== undefined ) { console.log( "Adding " + $.trim(item) ); } } }( window.skillet = window.skillet || {}, jQuery )); //Public Properties console.log( skillet.ingredient ); //Bacon Strips //Public Methods skillet.fry(); //Adding Butter & Fraying Bacon Strips //Adding a Public Property skillet.quantity = "12"; console.log( skillet.quantity ); //12 //Adding New Functionality to the Skillet (function( skillet, $, undefined ) { //Private Property var amountOfGrease = "1 Cup"; //Public Method skillet.toString = function() { console.log( skillet.quantity + " " + skillet.ingredient + " & " + amountOfGrease + " of Grease" ); console.log( isHot ? "Hot" : "Cold" ); }; }( window.skillet = window.skillet || {}, jQuery )); //end of skillet definition try { //12 Bacon Strips & 1 Cup of Grease skillet.toString(); //Throws Exception } catch( e ) { console.log( e.message ); //isHot is not defined } I feel that I should mention that the Self-Executing Anonymous Function is the pattern used by the jQuery team. Update When I asked this question I didn't truly see the importance of what I was trying to understand. The real issue at hand is whether or not to use new to create instances of your objects or to use patterns which do not require constructors of the use of the new keyword. I added my own answer, because in my opinion we should make use of patterns which don't use the new keyword. For more information please see my answer.

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  • Can't boot Ubuntu 12.10 graphics problem

    - by Frantumn
    I can't boot since installing Ubuntu 12.10 When I try to run Ubuntu My computer never gets to the Ubuntu screen with the loading dots. I tried to run in recovery mode with safe graphics (failsafex) When I do this a message pops up saying "the system is running in low graphics mode", If I click okay I am asked what would I like to do and am given four options. I tried running low graphics for one session and then a message appears with a progress bar and says standby one minute while the display restarts. The progress bar never moves and if I click okay the whole process just restarts. I Don't know what to do from here I can't get into the OS. I'm not sure whether the problem is related to compatibility with my laptop monitor or my graphic card nvidia360m I had to install using a safe graphics mode. To learn about how I installed see this link. This link also has information on my computer hardware. Can't install Ubuntu since 10.10 ----UPDATE--- I was able to get into a desktop environment By installing Nvidia-current however it is messy. I have a screen and I am able to see my desktop however there is no unity bar and none of the keyboard controls work. I can right click and create a folder on the desktop and then I can see inside that folder in a traditional browser window. There is still no top menu or unity bar. When I boot normally I don't get into the desktop environment and I get this message in tty 'GPU lockup switching to software FBCON' Okay, I've played around with tips the pages from comments. I've been able to consistantly get into a safemode desktop environment using the xorg & nouveau drivers. I've tried switching between the 5 different options in the Additional Drivers tab in Software Sources. The nVidia (proprietary, tested) driver gets beyond the GPU lockup on a normal boot and actually gets into a Desktop. The issue is then that there is no Unity bar, or top screen menu bar and the resolution is very low. I've tried switching to the (prop, tested) driver and then reinstalling Unity and Ubuntu-Desktop but that didn't work either.

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  • Failed to start up after upgrading software in ubuntu 10.10

    - by Landy
    I asked this question in SuperUser one hour ago, then I know this community so I moved the question here... I've been running Ubuntu 10.10 in a physical x86-64 machine. Today Update Manager reminded me that there are some updates to install and I confirmed the action. I should had read the update list but I didn't. I can only remember there is an update about cups. After the upgrading, Update Manager requires a restart and I confirmed too. But after the restart, the computer can't start up. There are errors in the console. Begin: Running /scripts/init-premount ... done. Begin: Mounting root file system ... Begin: Running /scripts/local-top ... done. [xxx]usb 1-8: new high speed USB device using ehci_hcd and address 3 [xxx]usb 2-1: new full speed USB device using ohci_hcd and address 2 [xxx]hub 2-1:1.0: USB hub found [xxx]hub 2-1:1.0: 4 ports detected [xxx]usb 2-1.1: new low speed USB device using ohci_hcd and address 3 Gave up waiting for root device. Common probles: - Boot args (cat /proc/cmdline) - Check rootdelay=(did the system wait long enough) - Check root= (did the system wait for the right device?) - Missing modules (cat /proc/modules; ls /dev) FATAL: Could not load /lib/modules/2.6.35-22-generic/modules.dep: No such file or directory FATAL: Could not load /lib/modules/2.6.35-22-generic/modules.dep: No such file or directory ALERT! /dev/sda1 does not exist. Dropping to a shell! BusyBox v1.15.3 (Ubuntu 1:1.15.3-1ubuntu5) built-in shell(ash) Enter 'help' for a list of built-in commands. (initramfs)[cursor is here] At the moment, I can't input anything in the console. The keyboard doesn't work at all. What's wrong? How can I check boot args or "root=" as suggested? How can I fix this issue? Thanks. =============== PS1: the /dev/sda1 is type ext4 (rw,nosuid,nodev) PS2: the /dev/sda1 can be mounted and accessed successfully under SUSE 11 SP1 x64. PS3: From this link, I think the keyboard doesn't work because the USB driver is not loaded at that time.

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  • Good, simple reasons for having multiple environments

    - by smp7d
    Throughout my career I had worked at companies that had a collection of different environments for different purposes. We always had more or less our desktop environment, a test environment, a QA environment, a staging environment and a production environment. This went for both servers/applications and any data sources we were using. When I started at my current company I found that 90% of the apps were either developed on a desktop environment against production data sources or developed directly on the production server depending on the platform. I wasn't fazed because I was hired in part to make changes to improve the way the development team functioned, which was clear from my interview process. We slowly started to turn the philosophy and pretty soon, most of the apps could be run in either a desktop, test or production environment. Not too long after that staging came around as well. Now most of our developers see the benefit of this methodology and defend it vigilantly. However, we have a number of legacy apps that never got migrated. We also have a number of legacy programmers who think of this as a waste of time. Unfortunately, we got lip service but never full buy-in from management. We got what we thought was a commitment to invest substantially in this about a year ago, but nothing materialized despite the considerable planning that we put into it. Now we are finding that we need more and more environments. We need help from the server/network administration teams for setup and we need participation from the business stakeholders to support the release cycle. We are at a place now where a project can function what I consider "normally" only if you have the right people on the project and the time to set up the proper environments. I'd love to present a complete argument, but management really has no time and interest in hearing me out until there is a critical issue. I can't really articulate the benefits simply as it always just seemed second nature to me. I was wondering if there are any good, simple, irrefutable reasons for the separation of environments that would get managers with no development experience to get behind this idea. Are there any good resources/literature on the topic?

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  • Event Driven Behavior Tree: deterministic traversal order with parallel

    - by Heisenbug
    I've studied several articles and listen some talks about behavior trees (mostly the resources available on AIGameDev by Alex J. Champandard). I'm particularly interested on event driven behavior trees, but I have still some doubts on how to implement them correctly using a scheduler. Just a quick recap: Standard Behavior Tree Each execution tick the tree is traversed from the root in depth-first order The execution order is implicitly expressed by the tree structure. So in the case of behaviors parented to a parallel node, even if both children are executed during the same traversing, the first leaf is always evaluated first. Event Driven BT During the first traversal the nodes (tasks) are enqueued using a scheduler which is responsible for updating only running ones every update The first traversal implicitly produce a depth-first ordered queue in the scheduler Non leaf nodes stays suspended mostly of the time. When a leaf node terminate(either with success or fail status) the parent (observer) is waked up allowing the tree traversing to continue and new tasks will be enqueued in the scheduler Without parallel nodes in the tree there will be up to 1 task running in the scheduler Without parallel nodes, the tasks in the queue(excluding dynamic priority implementation) will be always ordered in a depth-first order (is this right?) Now, from what is my understanding of a possible implementation, there are 2 requirements I think must be respected(I'm not sure though): Now, some requirements I think needs to be guaranteed by a correct implementation are: The result of the traversing should be independent from which implementation strategy is used. The traversing result must be deterministic. I'm struggling trying to guarantee both in the case of parallel nodes. Here's an example: Parallel_1 -->Sequence_1 ---->leaf_A ---->leaf_B -->leaf_C Considering a FIFO policy of the scheduler, before leaf_A node terminates the tasks in the scheduler are: P1(suspended),S1(suspended),leaf_A(running),leaf_C(running) When leaf_A terminate leaf_B will be scheduled (at the end of the queue), so the queue will become: P1(suspended),S1(suspended),leaf_C(running),leaf_B(running) In this case leaf_B will be executed after leaf_C at every update, meanwhile with a non event-driven traversing from the root node, the leaf_B will always be evaluated before leaf_A. So I have a couple of question: do I have understand correctly how event driven BT work? How can I guarantee the depth first order is respected with such an implementation? is this a common issue or am I missing something?

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  • Bump mapping Problem GLSL

    - by jmfel1926
    I am having a slight problem with my Bump Mapping project. Although everything works OK (at least from what I know) there is a slight mistake somewhere and I get incorrect shading on the brick wall when the light goes to the one side or the other as seen in the picture below: The light is on the right side so the shading on the wall should be the other way. I have provided the shaders to help find the issue (I do not have much experience with shaders). Shaders: varying vec3 viewVec; varying vec3 position; varying vec3 lightvec; attribute vec3 tangent; attribute vec3 binormal; uniform vec3 lightpos; uniform mat4 cameraMat; void main() { gl_TexCoord[0] = gl_MultiTexCoord0; gl_Position = ftransform(); position = vec3(gl_ModelViewMatrix * gl_Vertex); lightvec = vec3(cameraMat * vec4(lightpos,1.0)) - position ; vec3 eyeVec = vec3(gl_ModelViewMatrix * gl_Vertex); viewVec = normalize(-eyeVec); } uniform sampler2D colormap; uniform sampler2D normalmap; varying vec3 viewVec; varying vec3 position; varying vec3 lightvec; vec3 vv; uniform float diffuset; uniform float specularterm; uniform float ambientterm; void main() { vv=viewVec; vec3 normals = normalize(texture2D(normalmap,gl_TexCoord[0].st).rgb * 2.0 - 1.0); normals.y = -normals.y; //normals = (normals * gl_NormalMatrix).xyz ; vec3 distance = lightvec; float dist_number =length(distance); float final_dist_number = 2.0/pow(dist_number,diffuset); vec3 light_dir=normalize(lightvec); vec3 Halfvector = normalize(light_dir+vv); float angle=max(dot(Halfvector,normals),0.0); angle= pow(angle,specularterm); vec3 specular=vec3(angle,angle,angle); float diffuseterm=max(dot(light_dir,normals),0.0); vec3 diffuse = diffuseterm * texture2D(colormap,gl_TexCoord[0].st).rgb; vec3 ambient = ambientterm *texture2D(colormap,gl_TexCoord[0].st).rgb; vec3 diffusefinal = diffuse * final_dist_number; vec3 finalcolor=diffusefinal+specular+ambient; gl_FragColor = vec4(finalcolor, 1.0); }

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  • What is the best way to implement collision detection using Bullet physics engine and a track generated from a curve?

    - by tigrou
    I am developing a small racing game were the track is generated from a curve. As said above, the track is generated, but not infinite. The track of one level could fit with no problem in memory and will contain a reasonably small amount of triangles. For collisions, I would like to use Bullet physics engine and know what is the best way to handle collisions with the track efficiently. NOTE : The track will be stored as a static rigid body (mass = 0). The player will be represented by a sphere shape for collisions. Here is some possibilities i have in mind : Create one rigid body, then, put all triangles of the track (except non collidable stuff) into it. Result : 1 body with many triangles (eg : 30000 triangles) Split the track into several sections (eg: 10 sections). Then, for each section, create a rigid body and put corresponding triangles in it. Result : small amount of bodies with relatively small amount of triangles (eg : 1500 triangles per section). Split the track into many sub-sections (eg : 1200 sections). Here one subsection = very small step when generating the curve. Again for each sub-section, create a body and put triangles in it. Result : many bodies with very small amount of triangles (eg : 20 triangles). Advantage : it could be possible to "extra data" to each of the subsection, that could be used when handling collisions. Same as 2, but only put sections N and N+1 in physics engine (where N = current section where the player is). When player reach section N+1, unload section N and load section N+2 and so on... Issue : harder to implement, problems if the player suddenly "jump" from one section to another (eg : player fly away from section N, and fall on section N + 4 that was underneath : no collision handled, player will fall into void ) Same as 4, but with many sub-sections. Issues : since subsections are very small there will be constantly new bodies added and removed to physics engine at runtime. Possibilities for player to accidently skip some sections and fall into the void are higher than 4.

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  • prism and multiple screens

    - by Avi
    OK - I am studying Prism a little because of a "free weekend" offer on Pluralsight. As this is proving too complex for me, I went to the Prism book and looked at the forward, and this is what it said: What comes after “Hello, World?” WPF and Silverlight developers are blessed with an abundance of excellent books... There’s no lack of tutorials on Model-View-ViewModel ... But they stop short of the guidance you need to deliver a non-trivial application in full. Your first screen goes well. You add a second screen and a third. Because you started your solution with the built-in “Navigation Application Template,” adding new screens feels like hanging shirts on a closet rod. You are on a roll. Until the harsh reality of real application requirements sets in. As it happens, your application has 30 screens not three. There’s no room on that closet rod for 30 screens. Some screens are modal pop-ups; you don’t navigate to a pop-up. Screens become interdependent such that user activity in one screen triggers changes that propagate throughout the UI. Some screens are optional; others are visible only to authorized users. Some screens are permanent, while other screens can be opened and closed at will. You discover that navigating back to a previously displayed screen creates a new instance. That’s not what you expected and, to your horror, the prior instance is gone along with the user’s unsaved changes. Now the issue is, I don't relate to this description. I've never been a UI programmer, but same as everyone else I'm using Windows apps such as MS-Office, and web sites such as Amazon, Facebook and StackExchange. And I look at these and I don't see many "so many screens" issues! Indeed, the only applications having many windows I can think of is Visual Studio. Maybe also Visio, a little. But take Word - You have a ribbon and a main window. Or take Facebook: You have those lists on the left (Favorites, Lists, Groups etc.), the status middle, the adds and then the Contacts sidebar. But it's only one page. Of course, I understand that in enterprise scenarios there are dashboad applications where multiple segments of the screen are updated from multiple non-related services. This I dig. But other scenarios? So - What am I missing? What is the "multiple screens" monster Pirsm is supposed to be the silver bullet solution for? Shoud I invest in studying Prism in addition to learning WPF or ASP.NET MVC?

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  • Getting a virus is *very* annoying

    - by bconlon
    I spent most of yesterday removing an annoying virus from my PC. I feel slightly foolish for getting one in the first place, but after so many years I guess I was always going to eventually succumb. I was also a little surprised at the failure of various tools at removing it. The virus would redirect the browser to websites including ‘licosearch’, ‘hugosearch’ and ‘facebook’, and the disk would be thrashing away infecting dlls in some way. I had the full up to date version of McAfee installed. This identified that there was an issue in some dlls on the system and was able to ‘fix’ them. But they kept getting re-infected. So I installed Microsoft Security Essentials and this too was able to identify and ‘fix’ the infected dlls. The system scans take forever and I really expected better results. I also tried Malwarebytes, Hitman Pro, AVG and Sophos to no avail. Eventually I thought I’d investigate myself. It turned out that on reboot, the virus would start 3 instances of Firefox.exe which I’m guessing would do bad things including infecting as many dlls on the system as possible. I removed Firefox and the virus cleverly then launched 3 instances of Chrome! So I uninstalled Chrome and yes, it then started to launch 3 instances of iexplore.exe. If I’m honest, by this stage I was just seeing if it would be able to use any of the browsers! As it was starting these on reboot, I looked in my User Startup folder and there was a <randomly named>.exe and several log files. I deleted these and rebooted. When I looked they had been recreated. So I then looked in the registry Run and RunOnce entries: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run. Sure enough there were entries to run a file in C:\Program Files\<random name folder>\<random name file>.exe. I deleted this and rebooted and it was fixed. I also looked in the event log and found a warning that Winlogon had failed to start the file C:\Program Files\<random name folder>\<random name file>.exe So I also checked HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon and this entry had also been changed. Finally I ran a full system scan to clean up any infected dlls. I hope it’s gone for good!  #

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  • 2D Collision in Canvas - Balls Overlapping When Velocity is High

    - by kushsolitary
    I am doing a simple experiment in canvas using Javascript in which some balls will be thrown on the screen with some initial velocity and then they will bounce on colliding with each other or with the walls. I managed to do the collision with walls perfectly but now the problem is with the collision with other balls. I am using the following code for it: //Check collision between two bodies function collides(b1, b2) { //Find the distance between their mid-points var dx = b1.x - b2.x, dy = b1.y - b2.y, dist = Math.round(Math.sqrt(dx*dx + dy*dy)); //Check if it is a collision if(dist <= (b1.r + b2.r)) { //Calculate the angles var angle = Math.atan2(dy, dx), sin = Math.sin(angle), cos = Math.cos(angle); //Calculate the old velocity components var v1x = b1.vx * cos, v2x = b2.vx * cos, v1y = b1.vy * sin, v2y = b2.vy * sin; //Calculate the new velocity components var vel1x = ((b1.m - b2.m) / (b1.m + b2.m)) * v1x + (2 * b2.m / (b1.m + b2.m)) * v2x, vel2x = (2 * b1.m / (b1.m + b2.m)) * v1x + ((b2.m - b1.m) / (b2.m + b1.m)) * v2x, vel1y = v1y, vel2y = v2y; //Set the new velocities b1.vx = vel1x; b2.vx = vel2x; b1.vy = vel1y; b2.vy = vel2y; } } You can see the experiment here. The problem is, some balls overlap each other and stick together while some of them rebound perfectly. I don't know what is causing this issue. Here's my balls object if that matters: function Ball() { //Random Positions this.x = 50 + Math.random() * W; this.y = 50 + Math.random() * H; //Random radii this.r = 15 + Math.random() * 30; this.m = this.r; //Random velocity components this.vx = 1 + Math.random() * 4; this.vy = 1 + Math.random() * 4; //Random shade of grey color this.c = Math.round(Math.random() * 200); this.draw = function() { ctx.beginPath(); ctx.fillStyle = "rgb(" + this.c + ", " + this.c + ", " + this.c + ")"; ctx.arc(this.x, this.y, this.r, 0, Math.PI*2, false); ctx.fill(); ctx.closePath(); } }

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  • How do I know if I am using Scrum methodologies?

    - by Jake
    When I first started at my current job, my purpose was to rewrite a massive excel-VBA workbook-application to C# Winforms because it was thought that the new C# app will fix all existing problems and have all the new features for a perfect world. If it were a direct port, in theory it would be easy as i just need to go through all the formulas, conditional formatting, validations, VBA etc. to understand it. However, that was not the case. Many of the new features are tightly dependant on business logic which I am unfamiliar with. As a solo programmer, the first year was spent solely on deciphering the excel workbook and writing the C# app. In theory, I had the business people to "help" me specify requirements, how GUI looks and work, and testing of the app etc; but in practice it is like a contant tsunami of feature creep. At the beginning of the second year I managed to convince the management that this is not going anywhere. I made them start from scratch with the excel-VBA. I have this "issue log" saved on the network, each time they found something they didn't like about the excel-VBA app, they will write it in there. I check the log daily and consolidate issues (in my mind) mainly into 2 groups: (1) requires massive change. (2) can be fixed in current version. For massive change issues, I make a copy of the latest excel-VBA and give it a new version number, then work on it whenever I can. For current version fixes, I make the changes in a few days to a week, and then immediately release it. I also ensure I update the same change in any in-progress massive change future versions. This has gone on for about 4 months and I feel it works great. I made many releases and solved many real issues, also understood the business logic more and more. However, my boss (non-IT trained) thinks what I am doing are just adhoc changes and that i am not looking at the "bigger picture". I am struggling to convince my boss that this works. So I hope to formalise my approach and maybe borrow a buzzword to confuse him. Incidentally, I read about Agile and SCRUM, about backlog and sprints. But it's all very vague to me still. QUESTION (finally): I want to tell him that this is SCRUM! But I want to hold my breath first and ask whether my current approach is considered SCRUM or SCRUM-like? How can I make it more SCRUM-like? Note that I have only myself, there's no project leader or teams.

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  • SEO effects of intermix of WP blog, custom PHP site and FB app game

    - by melbournetechlover
    We're a melbourne tech company in the process of building a custom site in PHP. We plan to launch a "pre-launch" page which is also custom coded (CSS3 on twitter bootstrap framework + HTML5 front end and PHP back end). On that site will be a link to a blog - the idea behind this is to build up ranking for a variety of relevant keywords prior to the full site going live (given the majority of the site is a member only community anyway so the blog is really the main way we'll be able to execute on-site SEO. Ideally, we would like to install wordpress in a subdirectory on our servers and just customise the header to look the same as the landing page of the website. But some questions and concerns... Is there any detrimental effect on SEO efforts in having two separate systems (one custom PHP, the other an installation of wordpress) to manage the blog vs the rest of the site? Are there any benefits or detriments to installing on a sub domain such as blog.sitename.com vs. sitename.com/blog. My preference would be sitename.com/blog as it feels neater - but open to suggestions based on knowledge of Google preferences. Separately, we are building a Facebook app which is under another site name. Again because we are launching this app first, from an SEO perspective, would it actually be better to run it from a sub domain on the main site - e.g. gamename.mainsitename.com instead of on app.gamename.com? Currently we have it on app.gamename.com, but if there are SEO benefits to moving it to the other domain and server then we'll do it. Basically we don't want to have our SEO efforts divided - will Google algorithms prefer two sites heavily referring traffic, or is it better to focus our efforts on one. I guess that's the crux of the issue. But the other one is - does Google care about traffic accessing a page built for the Facebook app iFrame - does that count toward rankings? Sorry I hope these questions aren't too complex - but we're in the tech world every day and still can't seem to find a good answer to these ones...hence I'm taking to the forums!! Free beer for whoever can give me a solid answer!

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  • SQL Saturday 194 - Exeter

    - by Dave Ballantyne
    Many kudos goes to Jonathan and Annette Allen and the others on the team for confirming SQL Saturday 194 in Exeter on the 8th and 9th of March.  The event home page is here http://www.sqlsaturday.com/194/eventhome.aspx and I delighted that myself and Dave Morrison will be presenting a full day pre-con on the 8th on favourite subjects “TSQL and Internals”. Here is the full abstract : TSQL and internals - When faced with performance issues there are many lines of attack. Tuning the engine itself can get you so far, however for maximum effect you need to understand how the engine and how it translates SQL statements into performable actions. This is not a simple task, it is a massive task to deal with a multi-table join and the number of permutations can be immense. To back up this knowledge, we can create better performing TSQL and understand the impact that is has upon the engine and recognize the pitfalls and gotcha’s that exist in SQLServer. Ultimately, there is no ‘best way’ to perform a single task only many variations of ‘it depends’ , but now we can pick the most appropriate option for the required dataload. Over the years, there have been many myths and misconceptions have grown around the product, some have basis in older versions and some are just wrong. Continuing to build on the knowledge given so far these issue will be explored and broken down and proved or disproved. Finally we will look to the future and explore SQL Server 2012 and the new functionality that that brings and some of the common uses that we will be able to address. After completion of this days pre-con, attendees will have a more complete knowledge of execution plans, and how they relate to the physical and logical actions that SQLServer will be executing on their behalf. The attendees will also have a more rounded and fuller knowledge of TSQL and the implications of incorrectly defining a query. Dave is a fountain of knowledge on execution plans and optimizer internals and ,though i may flatter myself, I’m no shrinking violet when it comes to TSQL and such matters.  I hope that if you cant join us, then there are other pre-cons available from other experts in their fields that may ‘float you boat’ too.  The pre-con page is http://sqlsouthwest.co.uk/SQLSaturday_precon.htm Also, excitingly, this pre-con day is sponsored by Fusion-IO which is a great boon for the day. If you want a more of this then i am offering a 2 day TSQL course starting on the 19th of March. More details on this are available here

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  • SSH from external network refused

    - by wulfsdad
    I've installed open-ssh-server on my home computer(running Lubuntu 12.04.1) in order to connect to it from school. This is how I've set up the sshd_config file: # Package generated configuration file # See the sshd_config(5) manpage for details # What ports, IPs and protocols we listen for #Port 22 Port 2222 # Use these options to restrict which interfaces/protocols sshd will bind to #ListenAddress :: #ListenAddress 0.0.0.0 Protocol 2 # HostKeys for protocol version 2 HostKey /etc/ssh/ssh_host_rsa_key HostKey /etc/ssh/ssh_host_dsa_key HostKey /etc/ssh/ssh_host_ecdsa_key #Privilege Separation is turned on for security UsePrivilegeSeparation yes # Lifetime and size of ephemeral version 1 server key KeyRegenerationInterval 3600 ServerKeyBits 768 # Logging SyslogFacility AUTH #LogLevel INFO LogLevel VERBOSE # Authentication: LoginGraceTime 120 PermitRootLogin no StrictModes yes RSAAuthentication yes PubkeyAuthentication yes #AuthorizedKeysFile %h/.ssh/authorized_keys # Don't read the user's ~/.rhosts and ~/.shosts files IgnoreRhosts yes # For this to work you will also need host keys in /etc/ssh_known_hosts RhostsRSAAuthentication no # similar for protocol version 2 HostbasedAuthentication no # Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication #IgnoreUserKnownHosts yes # To enable empty passwords, change to yes (NOT RECOMMENDED) PermitEmptyPasswords no # Change to yes to enable challenge-response passwords (beware issues with # some PAM modules and threads) ChallengeResponseAuthentication no # Change to no to disable tunnelled clear text passwords #PasswordAuthentication yes # Kerberos options #KerberosAuthentication no #KerberosGetAFSToken no #KerberosOrLocalPasswd yes #KerberosTicketCleanup yes # GSSAPI options #GSSAPIAuthentication no #GSSAPICleanupCredentials yes X11Forwarding no X11DisplayOffset 10 PrintMotd no PrintLastLog yes TCPKeepAlive yes #UseLogin no #MaxStartups 10:30:60 #Banner /etc/issue.net Banner /etc/sshbanner.net # Allow client to pass locale environment variables AcceptEnv LANG LC_* Subsystem sftp /usr/lib/openssh/sftp-server # Set this to 'yes' to enable PAM authentication, account processing, # and session processing. If this is enabled, PAM authentication will # be allowed through the ChallengeResponseAuthentication and # PasswordAuthentication. Depending on your PAM configuration, # PAM authentication via ChallengeResponseAuthentication may bypass # the setting of "PermitRootLogin without-password". # If you just want the PAM account and session checks to run without # PAM authentication, then enable this but set PasswordAuthentication # and ChallengeResponseAuthentication to 'no'. UsePAM yes #specify which accounts can use SSH AllowUsers onlyme I've also configured my router's port forwarding table to include: LAN Ports: 2222-2222 Protocol: TCP LAN IP Address: "IP Address" displayed by viewing "connection information" from right-click menu of system tray Remote Ports[optional]: n/a Remote IP Address[optional]: n/a I've tried various other configurations as well, using primary and secondary dns, and also with specifying remote ports 2222-2222. I've also tried with TCP/UDP (actually two rules because my router requires separate rules for each protocol). With any router port forwarding configuration, I am able to log in with ssh -p 2222 -v localhost But, when I try to log in from school using ssh -p 2222 onlyme@IP_ADDRESS I get a "No route to host" message. Same thing when I use the "Broadcast Address" or "Default Route/Primary DNS". When I use the "subnet mask", ssh just hangs. However, when I use the "secondary DNS" I recieve a "Connection refused" message. :^( Someone please help me figure out how to make this work.

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  • I didn't mean to become a database developer, but now I am. Should I stop or try to get better?

    - by pretlow majette
    20 years ago I couldn't afford even a cheap POS program when I opened my first surf shop in the Virgin Islands. I bought a copy of Paradox (remember that?) in 1990 and spent months in a back room scratching out a POS application. Over many iterations, including a switch to Access (2000)/SQL Server (2003), I built a POS and backoffice solution that runs four stores with multiple cash registers, a warehouse and office. Until recently, all my stores were connected to the same LAN (in a small shopping center) and performance wasn't an issue. Now that we've opened a location in the States that's changed. Connecting to my local server via the internet has slowed that locations application to a crawl. This is partly due to the slow and crappy dsl service we have in the Virgin Islands, and partly due to my less-than-professional code and sql. With other far-away stores in the works, I need a better solution. I like my application. My staff knows it well, and I'm not inclined to take on the expense of a proper commercial solution. So where does that leave me? I should probably host my sql online to sidestep the slow dsl here. I think I can handle cleaning up my SQL querries to speed that up a bit. What about Access? My version seems so old, but I don't like the newer versions with the 'ribbon'. There are so many options... Should I be learning Visual Studio with an eye on moving completely to the web? Will my VBA skills help me at all there? I don't have the luxury of a year at the keyboard to figure it out anymore. What about dotnetnuke, sharepoint, or lightswitch? They all seem like possibilities, but even understanding their capabilities is daunting. I'm pretty deep into it, but maybe I should bail and hire a consultant or programmer. That sounds expensive tho, and there's no guarantee there either... Any advice would be greatly appreciated. Or, if anybody is interested in buying a small chain of surf shops...

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  • Plans for Java 7 and E-Business Suite Certification

    - by Steven Chan (Oracle Development)
    As of June 2012, Java 7 has not been certified yet with Oracle E-Business Suite.  EBS customers should continue to run JRE 6 on their Windows end-user desktops, and JDK 6 on their EBS servers. If a search engine has brought you to this article, please check the Certifications summary for our latest certified Java release. Our plans for certifying Java 7 for the E-Business Suite We plan on releasing the Java 7 certification for E-Business Suite customers in two phases: Phase 1: Certify JRE 7 for Windows end-user desktops Phase 2: Certify JDK 7 for server-based components When will Java 7 be certified with EBS? We're working on the first phase now. As usual, I cannot discuss release dates here, but you can monitor or subscribe to this blog for updates. Current known issues with JRE 7 in EBS environments Our current testing shows that there are known incompatibilities between JRE 7 and the Forms-invocation process in EBS environments.  We have been working directly with the Java division on this for a while now.  In the meantime, EBS customers should not deploy JRE 7 to their end-user Windows desktop clients. You should stick with JRE 1.6 for now.  But wait, you previously said... Older JRE certification announcements stated: Our standard policy is that all E-Business Suite customers can apply all JRE updates to end-user desktops from JRE 1.6.0_03 and higher.  We test all new JRE releases in parallel with the JRE development process, so all JRE releases are considered certified with the E-Business Suite on the same day that they're released by our Java team.  You do not need to wait for a certification announcement before applying new JRE releases to your EBS users' desktops. Yes, this is true.  This standard boilerplate text was written before JRE 7 was released, so there was no possibility of misunderstanding.  With the availability of JRE 7, that boilerplate needs to be revised to read: Our standard policy is that all E-Business Suite customers can apply all JRE updates to end-user desktops from JRE 1.6.0_03 and later updates on the 1.6 codeline.  We test all new JRE 1.6 releases in parallel with the JRE development process, so all new JRE 1.6 releases are considered certified with the E-Business Suite on the same day that they're released by our Java team.  You do not need to wait for a certification announcement before applying new JRE 1.6 releases to your EBS users' desktops. References Recommended Browsers for Oracle Applications 11i (Metalink Note 285218.1) Upgrading Sun JRE (Native Plug-in) with Oracle Applications 11i for Windows Clients (Metalink Note 290807.1) Recommended Browsers for Oracle Applications 12 (MetaLink Note 389422.1) Upgrading JRE Plugin with Oracle Applications R12 (MetaLink Note 393931.1) Related Articles Mismanaged Session Cookie Issue Fixed for EBS in JRE 1.6.0_23 Roundup: Oracle JInitiator 1.3 Desupported for EBS Customers in July 2009

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  • Defining a service layer: the text-based adventure

    - by Stacy Vicknair
    Applications these days have more options than ever for a user interface, and it’s only going to grow. A successful product might require native applications for mobile devices, a regular web implementation, or even a gaming console. These systems often will be centralized and data driven. The solution is one that’s fairly solitary, a service layer! Simply put, take what’s shared and put it behind a physical or abstract layer that defines the boundary between the specific user interface and the shared content.   I know, I know, none of this is complicated. But some times it can be difficult to discern what belongs on which side of the line. For instance, say we’re creating a service that will provide content for both an ASP.NET MVC application and a WP7 application. Although the content served to each application is the same, there are different paradigms and patterns for displaying that data in the different environments. In ASP.NET MVC, you may create a model specific to a page that combines necessary information. In the WP7 application you might require different sets of data that you will connect via MVVM with the view. The general rule of thumb is that any shared content, business rules, or data should exist separately. Any element that is specific to the current UI implementation should be included in a separate library or with the UI implementation itself. The WP7 application doesn’t need my MVC specific model classes. My MVC application doesn’t require those INotifyPropertyChanged viewmodels that the WP7 application depends on. In both cases, there should be additional processing done above the service layer to massage the data to the application’s specific needs.   Service-ocalypse: the text based adventure What helps me the most about deciding whether or not something belongs coupled to the UI implementation or in the shared implementation is thinking of the simplest implementation you could have: a console application. You might have played a game like Peasant’s Quest: The console app is the text based adventure game version of your application. If you’re service was consumed in its simplest form, you would simply have a console based API for it that issues requests. Maybe those requests aren’t SWIM TO BOAT, but they might be CREATE USER JOHN. If I issue a request, I expect that request to be issued to the service. If the service has any exceptions or issues with my input, that business logic should be encapsulated in that service, not implemented in the UI. The service layer should be your functional application in its entirety, and anything above that layer should only assist with the display of that information.

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  • Link instead of Attaching

    - by Daniel Moth
    With email storage not being an issue in many companies (I think I currently have 25GB of storage on my email account, I don’t even think about storage), this encourages bad behaviors such as liberally attaching office documents to emails instead of sharing a link to the document in SharePoint or SkyDrive or some file share etc. Attaching a file admittedly has its usage scenarios too, but it should not be the default. I thought I'd list the reasons why sharing a link can be better than attaching files directly. In no particular order: Better Review. It allows multiple recipients to review the file and their comments are aggregated into a single document. The alternative is everyone having to detach the document, add their comments, then send back to you, and then you have to collate. Wirth the alternative, you also potentially miss out on recipients reading comments from other recipients. Always up to date. The attachment becomes a fork instead of an always up to date document. For example, you send the email on Thursday, I only open it on Tuesday: between those days you could have made updates that now I am missing because you decided to share a link instead of an attachment. Better bookmarking. When I need to find that document you shared, you are forcing me to search through my email (I may not even be running outlook), instead of opening the link which I have bookmarked in my browser or my collection of links in my OneNote or from the recent/pinned links of the office app on my task bar, etc. Can control access. If someone accidentally or naively forwards your link to someone outside your group/org who you’d prefer not to have access to it, the location of the document can be protected with specific access control. Can add more recipients. If someone adds people to the email thread in outlook, your attachment doesn't get re-attached - instead, the person added is left without the attachment unless someone remembers to re-attach it. If it was a link, they are immediately caught up without further actions. Enable Discovery. If you put it on a share, I may be able to discover other cool stuff that lives alongside that document. Save on storage. So this doesn't apply to me given my opening statement, but if in your company you do have such limitations, attaching files eats up storage on all recipients accounts and will also get "lost" when those people archive email (and lose completely at some point if they follow the company retention policy). Like I said, attachments do have their place, but they should be an explicit choice for explicit reasons rather than the default. Comments about this post by Daniel Moth welcome at the original blog.

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