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• Passed: Exam 70-480: Programming in HTML5 with JavaScript and CSS3

  First off: Mission accomplished successfully. And it was fun! Using the resources listed in my previous article about Learning Content, I'd like to thank Microsoft Technical Evangelists Jeremy Foster and Michael Palermo for their excellent jump start videos on Channel 9, and the various authors at Pluralsight. Local Prometric testing centre Back in November I chose a local testing centre which was the easiest to access from my office despite the horrible traffic you might experience here on the island. Actually, it was not the closest one. But due to their website, their awards as Microsoft Learning Center, and my general curiosity about the premises, I gave FRCI my priority. Boy, how should I regret this decision this morning... The official Prometric exam guide asks any attendee to show up at least 30 minutes prior to the scheduled time of the test. Well, this should have been the easier part but unfortunately due to heavier traffic than usual I arrived only 20 minutes before time. Not too bad but more to come. The building called 'le Hub' is nicely renovated and provides the right environment for an IT group of companies like FRCI. I think they have currently 5 independent IT departments over there. Even the handling at the reception was straight forward, welcoming and at my ease. But then... first shock: "We don't have any exam registration for today." - Hm, that's nice... Here's my mail confirmation from Prometric. First attack successfully handled and the lady went off again to check their records. Next shock: A couple of minutes later, another guy tries to explain me that "the staff of the testing centre is already on vacation and the centre is officially closed." - Are you kidding me? Here's the official confirmation by Prometric, and I don't find it funny that I take a day off today only to hear this kind of blubbering nonsense. I thought that I'll be on the safe side choosing a company with a good reputation here on the island. Another 40 (!) minutes later, they finally come back to the waiting area with a pre-filled form about the test appointment. And finally, after an hour of waiting, discussing, restarting the testing PC, and lots of talk, I am allowed to sit down and take the exam. Exam details Well, you know the rules. Signing an NDA doesn't allow me to provide you any details about the questions or topics that have been covered. Please check out the official exam description, and you're on the right way. Sorry, guys... ;-) The result "Congratulations! You have passed this Microsoft Certification exam." - In general, I have to admit that the parts on HTML5 and CSS3 were the easiest after all, and that I have to get myself a little bit more familiar with certain Javascript features like class definitions, inheritance and data security. Anyway, exam passed - who cares about the details? Next goal Of course, the journey to Microsoft Certifications continues and my next goal is to pass exams 70-481 - Essentials of Developing Windows Store Apps using HTML5 and JavaScript and 70-482 - Advanced Windows Store App Development using HTML5 and JavaScript. This would allow me to achieve the certification of MCSD: Windows Store Apps using HTML5. I guess, during 2013 I'll be busy with various learning and teaching lessons.

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• Notes - Part II - Play with JavaFX

  - by Silviu Turuga

  Open the project from last lesson Double click on NotesUI.fmxl, this will open the JavaFX Scene Builder On the left side you have a area called Hierarchy, from there press Del or Shift+Backspace on Mac to delete the Button and the Label. You'll receive a warning, that some components have been assigned an fx:id, click Delete as we don't need them anymore. Resize the AnchorPane to have enough room for our design, eg. 820x550px From the top left pick the Container called Accordion and drag over the AnchorPane design Chose then from Controls a List View and drag inside the Accordion. You'll notice that by default the Accordion has 2 TitledPane, and you can switch between them by clicking on their name. I'll let you the pleasure to do the rest in order to get the following result  Here is the list of objects used Save it and then return to NetBeans Run the application and it should be run without any issue. If you click on buttons they all are functional, but nothing happens as we didn't link them with any action. We'll see this in the next episode. Now, let's play a little bit with the application and try to resize it… Have you notice the behavior? If the form is too small, some objects aren't visible, if it is too large there is too much space . That's for sure something that your users won't like and you as a programmer have to care about this. From NetBeans double click NotesUI.fmxl so to return back to JavaFX Scene Builder Select the TextField from bottom left of Notes, the one where I put the text Category and then from the right part of JavaFX Scene Builder you'll notice a panel called Inspector. Chose Layout and then click on the dotted lines from left and bottom of the square, like you see in the below image This will make the textfield to have always the same distance from left and bottom no matter the size of the form. Save and run the application. Note that whenever the form is changing the Height, the Category TextField has the same distance from the bottom. Select Accordion and do the same steps but also check the top dotted line, because we want the Accordion to have the same height as the main form has. I'll let you the pleasure to do the same for the rest of components. It's very important to design an application that can be resize by user and in the same time, all the buttons are on place. Last step is to make sure our application is not getting smaller then a certain size, as this will hide parts of our layout. So select the AnchorPane and from Inspector go to Layout and note down the Width and Height. Go back to NetBeans and open the file Main.java and add the following code just after stage.setScene(scene); (around line 26) stage.setMinWidth(820); stage.setMinHeight(550); Use your own width and height. This will prevent user to reduce the width or height of your application to a value that will hide parts of your layout. So now you should have done most of the design part and next time we'll see how can we enter some data into our newly created application… Note: in case you miss something, here are the source files of the project till this point. 

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• Perfect End to a Bad Day

  - by TehGrumpyCoder

  Yesterday's post about A Bad Day at Work actually had an addendum to it. There were apparently a bunch of guys on ice skates last night competing in some sport way the hell and gone over on the other side of the valley, and enough people couldn't live without seeing them that they had all major arteries heading west honked. I mean honked... the traffic guy reported the 101 had 16 miles of backup... yikes. Since I worked downtown for a number of years, my fallback is to cut across the city on surface streets to get to one of my old 'haunts' and just drive it home from there. Of course with the 101 backed up, then I17 would logically be as well, so I kept the news on rather than my Zune and heard where the bad stuff was going North. I popped out on the freeway about 7 miles south of my exit. Got to the exit which is about a mile from the house without killing or maiming me or anyone else. Waited patiently at the light in the inside lane to make a left and go under the freeway proceeding West. The light changed, I had full green, I started through and whoa... I've got someone in a little rat car crossing my bow! A little explanation... I drive a 3/4 ton pickup with a V-10, extended cab and shell on the back. It's not jacked up, but it sits up pretty good and is longer than any parking place I've ever tried to put it into. I consider this truck to be the consolation prize for paying uninsured motorist coverage for 45 years and having Pilar Martinez totally destroy a 3/4 ton Silverado on March 1, 2007 by plowing into me at traffic speed while I was stopped at a light. If you pay for uninsured motorist coverage, ask your insurance agent *exactly* what that means... I bet it's different than what you think it means. But I digress, sorry... So here I am with a car that is shorter from top to road than the hood on my truck, and the driver thought it would be safe to run a red light and see if they could get past me before I got into the lane. The right side of my front bumper was almost into the driver's window when I hit the brakes and wheeled it left. Fortunately for all involved, I saw it soon enough, and pulled into the 2nd lane for making a left to go back South. I looked in my mirror, signalled a move, then moved over behind the yuck in the rat car. I then punched it, and the future hood ornament and I both made it through the next light. I pulled alongside to let her know that she was DEFINITELY Number 1 in my book, and it's a middle-age woman looking at me with a "sorry, it was an accident" show of pouty face and arms held up. Tough $hit lady... that may have worked when you were 18, but it's not working anymore, and it wasn't an accident... you ran a freakin' red light and almost got yourself killed. That just about put a bow on the day... I was home later than usual, pissed off about work stuff, pissed off at traffic, and now that. I ate dinner, watched a little TV, and was asleep about 9:30 exhausted. Hope today is better.

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• Why Are We Here?

  - by Jonathan Mills

  Back in the early 2000s, Toyota had a vision of building the number one best selling minivan in North America. Their current minivan, the Sienna, was small, underpowered, and badly needed help.  Yuji Yokoya was given the job of re-engineering the Sienna. There was just one problem, Yuji, lived in Japan. He did not know the people or places that he would be engineering for. Believe it or not, Japan is nothing like North America. So, what does a chief engineer do in a situation like that? He packed up his team and flew halfway around the world. He made a commitment to drive through every state in the US, every province in Canada, and Mexico. He met the people and drove the roads that the Sienna would be driving. And guess what, what he learned on that trip revolutionized the Sienna. The innovations he made, sent the Sienna to number one. Why? Because he knew who he was building his product for. He knew, why he was there.Let me ask you this, do you know why you are building what you are building? As a member of a product team, can you tell me how your product will be used in the real world? As you are writing code, building test plans, writing stories, or any of the other project tasks, can you picture the face of a person who will be using what you are building? All to often, the answer to those questions is, no. Why is it important? Because, every day, project team members make assumptions. Over a given project, it is safe to say project team members will make thousands of assumptions about what they are doing. And all to often, those assumptions are not quite right. Its not that they are not good at their job, its just that they don’t really know why they are there.So, what to do? First and foremost, stop doing what you are doing. Yes, really. Schedule some time to go visit the people who will be using your product. Don’t invite them to you, go to them. Watch them work. Interact with them. Ask them questions. Maybe even try it out yourself. This serves two purposes. One, It shows them that you care about them. They will be far more engaged in your project if they feel like you care. And nothing says you care more that spending some time. Second, if gives you the proper frame of reference for you work. It gives you something tangible to go back to as you are building your product. As you make the thousands of assumptions that you will make over the life of your project, it gives you something to see in your mind that makes it real to you.Ultimately, setting a proper frame of reference is critical to the overall success of a project. The funny thing is, it really does not even take that long. In most cases, a 2-3 hour session will give you most of what you need to get the right insight. For the project, it will be the best 2 hours you could spend.

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• Inside Red Gate - Exercising Externally

  - by simonc

  Over the next few weeks, we'll be performing experiments on SmartAssembly to confirm or refute various hypotheses we have about how people use the product, what is stopping them from using it to its full extent, and what we can change to make it more useful and easier to use. Some of these experiments can be done within the team, some within Red Gate, and some need to be done on external users. External testing Some external testing can be done by standard usability tests and surveys, however, there are some hypotheses that can only be tested by building a version of SmartAssembly with some things in the UI or implementation changed. We'll then be able to look at how the experimental build is used compared to the 'mainline' build, which forms our baseline or control group, and use this data to confirm or refute the relevant hypotheses. However, there are several issues we need to consider before running experiments using separate builds: Ideally, the user wouldn't know they're running an experimental SmartAssembly. We don't want users to use the experimental build like it's an experimental build, we want them to use it like it's the real mainline build. Only then will we get valid, useful, and informative data concerning our hypotheses. There's no point running the experiments if we can't find out what happens after the download. To confirm or refute some of our hypotheses, we need to find out how the tool is used once it is installed. Fortunately, we've applied feature usage reporting to the SmartAssembly codebase itself to provide us with that information. Of course, this then makes the experimental data conditional on the user agreeing to send that data back to us in the first place. Unfortunately, even though this does limit the amount of useful data we'll be getting back, and possibly skew the data, there's not much we can do about this; we don't collect feature usage data without the user's consent. Looks like we'll simply have to live with this. What if the user tries to buy the experiment? This is something that isn't really covered by the Lean Startup book; how do you support users who give you money for an experiment? If the experiment is a new feature, and the user buys a license for SmartAssembly based on that feature, then what do we do if we later decide to pivot & scrap that feature? We've either got to spend time and money bringing that feature up to production quality and into the mainline anyway, or we've got disgruntled customers. Either way is bad. Again, there's not really any good solution to this. Similarly, what if we've removed some features for an experiment and a potential new user downloads the experimental build? (As I said above, there's no indication the build is an experimental build, as we want to see what users really do with it). The crucial feature they need is missing, causing a bad trial experience, a lost potential customer, and a lost chance to help the customer with their problem. Again, this is something not really covered by the Lean Startup book, and something that doesn't have a good solution. So, some tricky issues there, not all of them with nice easy answers. Turns out the practicalities of running Lean Startup experiments are more complicated than they first seem! Cross posted from Simple Talk.

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• Framework for Everything - Where to begin? [Longer post]

  - by SquaredSoft

  Back story of this question, feel free to skip down for the specific question Hello, I've been very interested in the idea of abstract programming the last few years. I've made about 30 attempts at creating a piece of software that is capable of almost anything you throw at it. I've undertook some attempts at this that have taken upwards of a year, while getting close, never releasing it beyond my compiler. This has been something I've always tried wrapping my head around, and something is always missing. With the title, I'm sure you're assuming, "Yes of course you noob! You can't account for everything!" To which I have to reply, "Why not?" To give you some background into what I'm talking about, this all started with doing maybe a shade of gray hat SEO software. I found myself constantly having to create similar, but slightly different sets of code. I've gone through as many iterations of way to communicate on http as the universe has particles. "How many times am I going to have to write this multi-threaded class?" is something I found myself asking a lot. Sure, I could create a class library, and just work with that, but I always felt I could optimize what I had, which often was a large undertaking and typically involved frequent use of the CRTL+A keyboard shortcut, mixed with the delete button. It dawned on me that it was time to invest in a plugin system. This would allow me to simply add snippets of code. as time went on, and I could subversion stuff out, and distribute small chunks of code, rather than something that encompasses only a specific function or design. This comes with its own complexity, of course, and by the time I had finished the software scope for this addition, it hit me that I would want to add to everything in the software, not just a new http method, or automation code for a specific website. Great, we're getting more abstract. However, the software that I have in my mind comes down to a quite a few questions regarding its execution. I have to have some parameters to what I am going to do. After writing what the perfect software would do in my mind, I came up with this as a list of requirements: Should be able to use networking A "Macro" or "Expression system" which would allow people to do something like : =First(=ParseToList(=GetUrl("http://www.google.com?q=helloworld!"), Template.Google)) Multithreaded Able to add UI elements through some type of XML -- People can make their own addons etc. Can use third party API through the plugins, such as Microsoft CRM, Exchange, etc. This would allow the software to essentially be used for everything. Really, any task you wish to automate, in a simple way. Making the UI was as also extremely hard. How do you do all of this? Its very difficult. So my question: With so many attempts at this, I'm out of ideas how to successfully complete this. I have a very specific idea in my mind, but I keep failing to execute it. I'm a self taught programmer. I've been doing it for years, and work professionally in it, but I've never encountered something that would be as complex and in-depth as a system which essentially does everything. Where would you start? What are the best practices for design? How can I avoid constantly having to go back and optimize my software. What can I do to generalize this and draw everything out to completion. These are things I struggle with. P.s., I'm using c# as my main language. I feel like in this example, I might be hitting the outer limit of the language, although, I don't know if that is the case, or if I'm just a bad programmer. Thanks for your time.

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• Fun tips with Analytics

  - by user12620172

  If you read this blog, I am assuming you are at least familiar with the Analytic functions in the ZFSSA. They are basically amazing, very powerful and deep. However, you may not be aware of some great, hidden functions inside the Analytic screen. Once you open a metric, the toolbar looks like this: Now, I’m not going over every tool, as we have done that before, and you can hover your mouse over them and they will tell you what they do. But…. Check this out. Open a metric (CPU Percent Utilization works fine), and click on the “Hour” button, which is the 2nd clock icon. That’s easy, you are now looking at the last hour of data. Now, hold down your ‘Shift’ key, and click it again. Now you are looking at 2 hours of data. Hold down Shift and click it again, and you are looking at 3 hours of data. Are you catching on yet? You can do this with not only the ‘Hour’ button, but also with the ‘Minute’, ‘Day’, ‘Week’, and the ‘Month’ buttons. Very cool. It also works with the ‘Show Minimum’ and ‘Show Maximum’ buttons, allowing you to go to the next iteration of either of those. One last button you can Shift-click is the handy ‘Drill’ button. This button usually drills down on one specific aspect of your metric. If you Shift-click it, it will display a “Rainbow Highlight” of the current metric. This works best if this metric has many ‘Range Average’ items in the left-hand window. Give it a shot. Also, one will sometimes click on a certain second of data in the graph, like this:  In this case, I clicked 4:57 and 21 seconds, and the 'Range Average' on the left went away, and was replaced by the time stamp. It seems at this point to some people that you are now stuck, and can not get back to an average for the whole chart. However, you can actually click on the actual time stamp of "4:57:21" right above the chart. Even though your mouse does not change into the typical browser finger that most links look like, you can click it, and it will change your range back to the full metric. Another trick you may like is to save a certain view or look of a group of graphs. Most of you know you can save a worksheet, but did you know you could Sync them, Pause them, and then Save it? This will save the paused state, allowing you to view it forever the way you see it now.  Heatmaps. Heatmaps are cool, and look like this:  Some metrics use them and some don't. If you have one, and wish to zoom it vertically, try this. Open a heatmap metric like my example above (I believe every metric that deals with latency will show as a heatmap). Select one or two of the ranges on the left. Click the "Change Outlier Elimination" button. Click it again and check out what it does.  Enjoy. Perhaps my next blog entry will be the best Analytic metrics to keep your eyes on, and how you can use the Alerts feature to watch them for you. Steve 

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• Creating a voxel world with 3D arrays using threads

  - by Sean M.

  I am making a voxel game (a bit like Minecraft) in C++(11), and I've come across an issue with creating a world efficiently. In my program, I have a World class, which holds a 3D array of Region class pointers. When I initialize the world, I give it a width, height, and depth so it knows how large of a world to create. Each Region is split up into a 32x32x32 area of blocks, so as you may guess, it takes a while to initialize the world once the world gets to be above 8x4x8 Regions. In order to alleviate this issue, I thought that using threads to generate different levels of the world concurrently would make it go faster. Having not used threads much before this, and being still relatively new to C++, I'm not entirely sure how to go about implementing one thread per level (level being a xz plane with a height of 1), when there is a variable number of levels. I tried this: for(int i = 0; i < height; i++) { std::thread th(std::bind(&World::load, this, width, height, depth)); th.join(); } Where load() just loads all Regions at height "height". But that executes the threads one at a time (which makes sense, looking back), and that of course takes as long as generating all Regions in one loop. I then tried: std::thread t1(std::bind(&World::load, this, w, h1, h2 - 1, d)); std::thread t2(std::bind(&World::load, this, w, h2, h3 - 1, d)); std::thread t3(std::bind(&World::load, this, w, h3, h4 - 1, d)); std::thread t4(std::bind(&World::load, this, w, h4, h - 1, d)); t1.join(); t2.join(); t3.join(); t4.join(); This works in that the world loads about 3-3.5 times faster, but this forces the height to be a multiple of 4, and it also gives the same exact VAO object to every single Region, which need individual VAOs in order to render properly. The VAO of each Region is set in the constructor, so I'm assuming that somehow the VAO number is not thread safe or something (again, unfamiliar with threads). So basically, my question is two one-part: How to I implement a variable number of threads that all execute at the same time, and force the main thread to wait for them using join() without stopping the other threads? How do I make the VAO objects thread safe, so when a bunch of Regions are being created at the same time across multiple threads, they don't all get the exact same VAO? Turns out it has to do with GL contexts not working across multiple threads. I moved the VAO/VBO creation back to the main thread. Fixed! Here is the code for block.h/.cpp, region.h/.cpp, and CVBObject.h/.cpp which controls VBOs and VAOs, in case you need it. If you need to see anything else just ask. EDIT: Also, I'd prefer not to have answers that are like "you should have used boost". I'm trying to do this without boost to get used to threads before moving onto other libraries.

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• Intermittent internet connectivity

  - by Rob Oplawar

  UPDATED: I recently built a new computer and set it up to dual-boot Windows 7 and Ubuntu 11.10. In Windows, using the same hardware, my LAN connectivity is solid. In Ubuntu, however, my network interface periodically dies and resets itself; I'll have a solid connection for 30 seconds, and then it will go out for 30 seconds. When I tail the log: tail -f /var/log/kern.log I see "eth0 link up" messages appear periodically, corresponding with the return of connectivity. I posted the original question months ago, and misinterpreted what was going on. With a working Internet connection in Windows, I ignored the problem for some months. See my answer below for the solution (drivers). ORIGINAL POST In Ubuntu, although I maintain a solid connection to my LAN (pinging the router IP address consistently returns a good result), my internet connectivity drops in and out. When I continuously ping 74.125.227.18 (a google.com server), I get responses for a while, then I start getting "Destination Host Unreachable" for a while, then I get responses again. This happens consistently, dropping the connection for about 30 seconds out of every minute or two. Whether I configure my network via the network manager or via /etc/network/interfaces seems to make no difference. I configure with the following settings: address 192.168.1.101 network 192.168.1.0 gateway 192.168.1.99 (my router's IP address) netmask 255.255.255.0 (confirmed as the right netmask for the router) broadcast 192.168.1.255 (also confirmed with the router). ifconfig confirms that these settings are working: eth0 Link encap:Ethernet HWaddr 50:e5:49:40:da:a6 inet addr:192.168.1.101 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::52e5:49ff:fe40:daa6/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:11557 errors:0 dropped:11557 overruns:0 frame:11557 TX packets:13117 errors:0 dropped:211 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:9551488 (9.5 MB) TX bytes:1930952 (1.9 MB) Interrupt:41 Base address:0xa000 I get the same issue when I use automatic DHCP address settings, although I did confirm that there is no other machine on the network with the static IP address I want to use. As I said, the connection to the local network stays solid - I never have any trouble pinging 192.168.1.* - it's internet addresses that I intermittently cannot reach. It's not a DNS issue because pinging known IP addresses directly shows the same behavior. Also, I don't think it's a hardware issue, as I never have any internet connectivity problems on the same machine in Windows. The network hardware is built into the motherboard: Gigabyte Z68XP-UD3P. I managed to bring the OS fully up to date, according to the update manager, but it didn't fix the issue, and with my limited understanding of network architecture I'm at my wit's end. The only clue I can see is that ifconfig is reporting a lot of dropped packets, but I'm not sure what to do about it. UPDATE: It seems my problem is a little more generic than I described; now when I try pinging my router and google simultaneously, they both go unreachable at the same time. Running ifdown eth0 and then ifup eth0 brings it back temporarily; if I just wait it comes back after a couple of minutes. I'll broaden my search through intermittent network connectivity problems.

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• Review: Windows 8 - Initial Experience

  - by Tim Murphy

  I originally started this post when I had the Windows 8 preview setup on VirtualBox image.  I have since put the RTM bits on a Dell E6530 that is my new work laptop.  It isn’t a table so I am not getting the touch experience, but as a developer this makes the most sense for the moment. This is the first Windows OS that I have had to spend much time exploring to even get started.  The first thing I ran into was when I clicked on the desktop icon I was lost.  Where is the Start menu? Where are my programs?  How do I get back to the Metro environment?  I finally tried hitting the Windows button and it popped back out to the Metro screen. Once I got past that I found that the look of the Metro interface is clean and well organized.  It should be familiar to anyone who is already using a Zune or Windows Phone 7.  In the Desktop, aside from the lack of the Start button to bring up programs the desktop is just like the Windows 7 environment we are all used to.  I do have to say though that I don’t like popping out to the Metro screen to find program.  I think installers for programs like ones that developers usually work in for a desktop mode will need to give an option for creating a desktop icon and pinning to the task bar of the desktop. One of the things I do really enjoy is having live tiles in the Metro environment.  It is a nice way of feeding my need for constant information.  The one drawback though is that the task bar at the bottom of my screen used to be where I got this information without leaving what I was working on.  It allowed me to see current temperatures and when there were messages waiting.  I have since found that these still work as expected in the Desktop and Toast message keep you up on what is going on in the Metro apps. Thankfully familiar functionality like Alt-Tab and Windows-Tab still work regardless of if apps are in the Metro or the Desktop environment.  Add to this the ability to find any application on the Metro screen by simply typing and things get very comfortable. I also started exploring some of the apps.  If you want see a ton of stats on your team at a glance check out the Sports app.  What games are coming up? Who are the leaders in a number of stats?  The Weather and Finance apps have good features as well and I am sure they will improve as users supply feedback. I have had to install Visual Studio 2010 side-by-side with VS2012 because the Windows Phone 7 SDK would only install on VS2010.  This isn’t a Windows 8 issue per se, but something that you need to be aware of if you are a developer moving to the new ecosystem. The overall experience is a joy despite a few hiccups.  For anyone moving to Windows 8 in on a non-touch laptop or desktop I do suggest this list of keyboard shortcuts.  Enjoy. del.icio.us Tags: Windows 8,Win8,Metro,Review

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• Patterns for a tree of persistent data with multiple storage options?

  - by Robin Winslow

  I have a real-world problem which I'll try to abstract into an illustrative example. So imagine I have data objects in a tree, where parent objects can access children, and children can access parents: // Interfaces interface IParent<TChild> { List<TChild> Children; } interface IChild<TParent> { TParent Parent; } // Classes class Top : IParent<Middle> {} class Middle : IParent<Bottom>, IChild<Top> {} class Bottom : IChild<Middle> {} // Usage var top = new Top(); var middles = top.Children; // List<Middle> foreach (var middle in middles) { var bottoms = middle.Children; // List<Bottom> foreach (var bottom in bottoms) { var middle = bottom.Parent; // Access the parent var top = middle.Parent; // Access the grandparent } } All three data objects have properties that are persisted in two data stores (e.g. a database and a web service), and they need to reflect and synchronise with the stores. Some objects only request from the web service, some only write to it. Data Mapper My favourite pattern for data access is Data Mapper, because it completely separates the data objects themselves from the communication with the data store: class TopMapper { public Top FetchById(int id) { var top = new Top(DataStore.TopDataById(id)); top.Children = MiddleMapper.FetchForTop(Top); return Top; } } class MiddleMapper { public Middle FetchById(int id) { var middle = new Middle(DataStore.MiddleDataById(id)); middle.Parent = TopMapper.FetchForMiddle(middle); middle.Children = BottomMapper.FetchForMiddle(bottom); return middle; } } This way I can have one mapper per data store, and build the object from the mapper I want, and then save it back using the mapper I want. There is a circular reference here, but I guess that's not a problem because most languages can just store memory references to the objects, so there won't actually be infinite data. The problem with this is that every time I want to construct a new Top, Middle or Bottom, it needs to build the entire object tree within that object's Parent or Children property, with all the data store requests and memory usage that that entails. And in real life my tree is much bigger than the one represented here, so that's a problem. Requests in the object In this the objects request their Parents and Children themselves: class Middle { private List<Bottom> _children = null; // cache public List<Bottom> Children { get { _children = _children ?? BottomMapper.FetchForMiddle(this); return _children; } set { BottomMapper.UpdateForMiddle(this, value); _children = value; } } } I think this is an example of the repository pattern. Is that correct? This solution seems neat - the data only gets requested from the data store when you need it, and thereafter it's stored in the object if you want to request it again, avoiding a further request. However, I have two different data sources. There's a database, but there's also a web service, and I need to be able to create an object from the web service and save it back to the database and then request it again from the database and update the web service. This also makes me uneasy because the data objects themselves are no longer ignorant of the data source. We've introduced a new dependency, not to mention a circular dependency, making it harder to test. And the objects now mask their communication with the database. Other solutions Are there any other solutions which could take care of the multiple stores problem but also mean that I don't need to build / request all the data every time?

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• Get More Value From Your Oracle Premier Support Investment

  - by Get Proactive Customer Adoption Team

  Untitled Document The Return on Investment in Support Training I’m a typical software user. I’ve been using spreadsheets almost daily for the past 10 years or so. I know how to enter simple formulas, format cells, import files, and I can sort and filter. Sometimes I even use a pivot table. I never attended training. I learnt everything I know on the fly. Sometimes it was intuitive and easy, other times I had to spend minutes and even hours searching for a solution. Yet when I see what some other people can do with their spreadsheets, I know I’m utilizing maybe 15% of the functionality. Pity, one day I really have to sign up for training. Why haven’t I done it yet? Ah, you know, I’m a busy person, I have work to do. And if I need to use a feature that I am unfamiliar with, I’ll spend time on it only when I really need it. Now wait. When I recall how much time I spent trying to figure how things work compared to time I spent doing the productive work, I realize it was not insignificant. I’m unable to sum up all the time I spent ‘learning’ on the fly, but I’m sure it’s been days or even weeks. And after all this time, I’ve mastered 15% of its features. If only I had attended training years ago. That investment would have paid back 10 times! Working with My Oracle Support is no different. Our customers typically use simple search, create service requests, and download patches. They think they know how to use My Oracle Support. And they’re right. They know something but often they’re utilizing only a fragment of My Oracle Support’s potential. For the investment that has been made, using only a small subset of the capabilities offered in My Oracle Support leaves value on the table. There is much more available in My Oracle Support. Dozens of diagnostic tools and proactive health checks will keep verifying your Oracle environments against best practices that Oracle gathers every day thanks to our comprehensive knowledge management process. Automated patch recommendations will help prevent known issues, and upgrade planning and more is included in My Oracle Support. Why are you not utilizing all of these best practices, capabilities and tools? Is it because you don’t have time to invest 2-3 hours of your time to learn about the features? Simply because you think you can learn on the fly like I thought I could? Does learning on the fly how to properly use the Service Request escalation process when you already have critical issue sound like a good idea? My advice is: Invest your time now to learn how My Oracle Support can help you prevent issues on your systems. Learn how to find answers faster and resolve problems more efficiently. Understand how to properly complete a service request. Invest in Support training, offered at no additional cost to Oracle Premier Support customers. It will pay back quicker than you think. It will bring you more value than you think. Discover your advantage with Oracle Premier Support's Proactive Portfolio.

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• ADO and Two Way Storage Tiering

  - by Andy-Oracle

  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 We get asked the following question about Automatic Data Optimization (ADO) storage tiering quite a bit. Can you tier back to the original location if the data gets hot again? The answer is yes but not with standard Automatic Data Optimization policies, at least not reliably. That's not how ADO is meant to operate. ADO is meant to mirror a traditional view of Information Lifecycle Management (ILM) where data will be very volatile when first created, will become less active or cool, and then will eventually cease to be accessed at all (i.e. cold). I think the reason this question gets asked is because customers realize that many of their business processes are cyclical and the thinking goes that those segments that only get used during month end or year-end cycles could sit on lower cost storage when not being used. Unfortunately this doesn't fit very well with the ADO storage tiering model. ADO storage tiering is based on the amount of free and used space in the source tablespace. There are two parameters that control this behavior, TBS_PERCENT_USED and TBS_PERCENT_FREE. When the space in the tablespace exceeds the TBS_PERCENT_USED value then segments specified in storage tiering clause(s) can be moved until the percent of free space reaches the TBS_PERCENT_FREE value. It is worth mentioning that no checks are made for available space in the target tablespace. Now, it is certainly possible to create custom functions to control storage tiering, but this can get complicated. The biggest problem is insuring that there is enough space to move the segment back to tier 1 storage, assuming that that's the goal. This isn't as much of a problem when moving from tier 1 to tier 2 storage because there is typically more tier 2 storage available. At least that's the premise since it is supposed to be less costly, lower performing and higher capacity storage. In either case though, if there isn't enough space then the operation fails. In the case of a customized function, the question becomes do you attempt to free the space so the move can be made or do you just stop and return false so that the move cannot take place? This is really the crux of the issue. Once you cross into this territory you're really going to have to implement two-way hierarchical storage and the whole point of ADO was to provide automatic storage tiering. You're probably better off using heat map and/or business access requirements and building your own hierarchical storage management infrastructure if you really want two way storage tiering. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

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• Editing files without race conditions?

  - by user2569445

  I have a CSV file that needs to be edited by multiple processes at the same time. My question is, how can I do this without introducing race conditions? It's easy to write to the end of the file without race conditions by open(2)ing it in "a" (O_APPEND) mode and simply write to it. Things get more difficult when removing lines from the file. The easiest solution is to read the file into memory, make changes to it, and overwrite it back to the file. If another process writes to it after it is in memory, however, that new data will be lost upon overwriting. To further complicate matters, my platform does not support POSIX record locks, checking for file existence is a race condition waiting to happen, rename(2) replaces the destination file if it exists instead of failing, and editing files in-place leaves empty bytes in it unless the remaining bytes are shifted towards the beginning of the file. My idea for removing a line is this (in pseudocode): filename = "/home/user/somefile"; file = open(filename, "r"); tmp = open(filename+".tmp", "ax") || die("could not create tmp file"); //"a" is O_APPEND, "x" is O_EXCL|O_CREAT while(write(tmp, read(file)); //copy the $file to $file+".new" close(file); //edit tmp file unlink(filename) || die("could not unlink file"); file = open(filename, "wx") || die("another process must have written to the file after we copied it."); //"w" is overwrite, "x" is force file creation while(write(file, read(tmp))); //copy ".tmp" back to the original file unlink(filename+".tmp") || die("could not unlink tmp file"); Or would I be better off with a simple lock file? Appender process: lock = open(filename+".lock", "wx") || die("could not lock file"); file = open(filename, "a"); write(file, "stuff"); close(file); close(lock); unlink(filename+".lock"); Editor process: lock = open(filename+".lock", "wx") || die("could not lock file"); file = open(filename, "rw"); while(contents += read(file)); //edit "contents" write(file, contents); close(file); close(lock); unlink(filename+".lock"); Both of these rely on an additional file that will be left over if a process terminates before unlinking it, causing other processes to refuse to write to the original file. In my opinion, these problems are brought on by the fact that the OS allows multiple writable file descriptors to be opened on the same file at the same time, instead of failing if a writable file descriptor is already open. It seems that O_CREAT|O_EXCL is the closest thing to a real solution for preventing filesystem race conditions, aside from POSIX record locks. Another possible solution is to separate the file into multiple files and directories, so that more granular control can be gained over components (lines, fields) of the file using O_CREAT|O_EXCL. For example, "file/$id/$field" would contain the value of column $field of the line $id. It wouldn't be a CSV file anymore, but it might just work. Yes, I know I should be using a database for this as databases are built to handle these types of problems, but the program is relatively simple and I was hoping to avoid the overhead. So, would any of these patterns work? Is there a better way? Any insight into these kinds of problems would be appreciated.

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• XNA WP7 Texture memory and ContentManager

  - by jlongstreet

  I'm trying to get my WP7 XNA game's memory under control and under the 90MB limit for submission. One target I identified was UI textures, especially fullscreen ones, that would never get unloaded. So I moved UI texture loads to their own ContentManager so I can unload them. However, this doesn't seem to affect the value of Microsoft.Phone.Info.DeviceExtendedProperties.GetValue("ApplicationCurrentMemoryUsage"), so it doesn't look like the memory is actually being released. Example: splash screens. In Game.LoadContent(): Application.Instance.SetContentManager("UI"); // set the current content manager for (int i = 0; i < mSplashTextures.Length; ++i) { // load the splash textures mSplashTextures[i] = Application.Instance.Content.Load<Texture2D>(msSplashTextureNames[i]); } // set the content manager back to the global one Application.Instance.SetContentManager("Global"); When the initial load is done and the title screen starts, I do: Application.Instance.GetContentManager("UI").Unload(); The three textures take about 6.5 MB of memory. Before unloading the UI ContentManager, I see that ApplicationCurrentMemoryUsage is at 34.29 MB. After unloading the ContentManager (and doing a full GC.Collect()), it's still at 34.29 MB. But after that, I load another fullscreen texture (for the title screen background) and memory usage still doesn't change. Could it be keeping the memory for these textures allocated and reusing it? edit: very simple test: protected override void LoadContent() { // Create a new SpriteBatch, which can be used to draw textures. spriteBatch = new SpriteBatch(GraphicsDevice); PrintMemUsage("Before texture load: "); // TODO: use this.Content to load your game content here red = this.Content.Load<Texture2D>("Untitled"); PrintMemUsage("After texture load: "); } private void PrintMemUsage(string tag) { Debug.WriteLine(tag + Microsoft.Phone.Info.DeviceExtendedProperties.GetValue("ApplicationCurrentMemoryUsage")); } protected override void Update(GameTime gameTime) { // Allows the game to exit if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed) this.Exit(); // TODO: Add your update logic here if (count++ == 100) { GC.Collect(); GC.WaitForPendingFinalizers(); PrintMemUsage("Before CM unload: "); this.Content.Dispose(); GC.Collect(); GC.WaitForPendingFinalizers(); PrintMemUsage("After CM unload: "); red = null; spriteBatch.Dispose(); GC.Collect(); GC.WaitForPendingFinalizers(); PrintMemUsage("After SpriteBatch Dispose(): "); } base.Update(gameTime); } protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.CornflowerBlue); // TODO: Add your drawing code here if (red != null) { spriteBatch.Begin(); spriteBatch.Draw(red, new Vector2(0,0), Color.White); spriteBatch.End(); } base.Draw(gameTime); } This prints something like (it changes every time): Before texture load: 7532544 After texture load: 10727424 Before CM unload: 9875456 After CM unload: 9953280 After SpriteBatch Dispose(): 9953280

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• Delegates: A Practical Understanding

  - by samerpaul

  It's been a while since I have written on this blog, and I'm planning on reviving it this summer, since I have more time to do so again.I've also recently started working on the iPhone platform, so I haven't been as busy in .NET as before.In either case, today's blog post applies to both C# and Objective-C, because it's more about a practical understanding of delegates than it is about code. When I was learning coding, I felt like delegates was one of the hardest things to conceptually understand, and a lot of books don't really do a good job (in my opinion) of explaining it. So here's my stab at it.A Real Life Example of DelegatesLet's say there are three of you. You, your friend, and your brother. You're each in a different room in your house so you can't hear each other, even if you shout. 1)You are playing a computer game2) Friend is building a puzzle3) Brother is nappingNow, you three are going to stay in your room but you want to be informed if anything interesting is happening to the one of you. Let's say you (playing the computer game) want to know when your brother wakes up.You could keep walking to the room, checking to see if he's napping, and then walking back to your room. But that would waste a lot of time / resources, and what if you miss when he's awake before he goes back to sleep? That would be bad.Instead, you hand him a 2-way radio that works between your room and his room. And you inform him that when he wakes up, he should press a button on the radio and say "I'm awake". You are going to be listening to that radio, waiting for him to say he's awake. This, in essence, is how a delegate works.You're creating an "object" (the radio) that allows you to listen in on an event you specify. You don't want him to send any other messages to you right now, except when he wakes up. And you want to know immediately when he does, so you can go over to his room and say hi. (the methods that are called when a delegate event fires). You're also currently specifying that only you are listening on his radio.Let's say you want your friend to come into the room at the same time as you, and do something else entirely, like fluff your brother's pillow. You will then give him an identical radio, that also hooks into your brother's radio, and inform him to wait and listen for the "i'm awake" signal.Then, when your brother wakes up, he says "I'm awake!" and both you and your friend walk into the room. You say hi, and your friend fluffs the pillow, then you both exit.Later, if you decide you don't care to say hi anymore, you turn off your radio. Now, you have no idea when your brother is awake or not, because you aren't listening anymore.So again, you are each classes in this example, and each of you have your own methods. You're playing a computer game (PlayComputerGame()), your friend is building a puzzle (BuildPuzzle()) and your brother is napping (Napping()). You create a delegate (ImAwake) that you set your brother to do, when he wakes up. You listen in on that delegate (giving yourself a radio and turning it on), and when you receive the message, you fire a new method called SayHi()). Your friend is also wired up to the same delegate (using an identical radio) and fires the method FluffPillow().Hopefully this makes sense, and helps shed some light on how delegates operate. Let me know! Feel free to drop me a line at Twitter (preferred method of contact) here: samerabousalbi

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• Getting 2D Platformer entity collision Response Correct (side-to-side + jumping/landing on heads)

  - by jbrennan

  I've been working on a 2D (tile based) 2D platformer for iOS and I've got basic entity collision detection working, but there's just something not right about it and I can't quite figure out how to solve it. There are 2 forms of collision between player entities as I can tell, either the two players (human controlled) are hitting each other side-to-side (i. e. pushing against one another), or one player has jumped on the head of the other player (naturally, if I wanted to expand this to player vs enemy, the effects would be different, but the types of collisions would be identical, just the reaction should be a little different). In my code I believe I've got the side-to-side code working: If two entities press against one another, then they are both moved back on either side of the intersection rectangle so that they are just pushing on each other. I also have the "landed on the other player's head" part working. The real problem is, if the two players are currently pushing up against each other, and one player jumps, then at one point as they're jumping, the height-difference threshold that counts as a "land on head" is passed and then it registers as a jump. As a life-long player of 2D Mario Bros style games, this feels incorrect to me, but I can't quite figure out how to solve it. My code: (it's really Objective-C but I've put it in pseudo C-style code just to be simpler for non ObjC readers) void checkCollisions() { // For each entity in the scene, compare it with all other entities (but not with one it's already compared against) for (int i = 0; i < _allGameObjects.count(); i++) { // GameObject is an Entity GEGameObject *firstGameObject = _allGameObjects.objectAtIndex(i); // Don't check against yourself or any previous entity for (int j = i+1; j < _allGameObjects.count(); j++) { GEGameObject *secondGameObject = _allGameObjects.objectAtIndex(j); // Get the collision bounds for both entities, then see if they intersect // CGRect is a C-struct with an origin Point (x, y) and a Size (w, h) CGRect firstRect = firstGameObject.collisionBounds(); CGRect secondRect = secondGameObject.collisionBounds(); // Collision of any sort if (CGRectIntersectsRect(firstRect, secondRect)) { //////////////////////////////// // // // Check for jumping first (???) // // //////////////////////////////// if (firstRect.origin.y > (secondRect.origin.y + (secondRect.size.height * 0.7))) { // the top entity could be pretty far down/in to the bottom entity.... firstGameObject.didLandOnEntity(secondGameObject); } else if (secondRect.origin.y > (firstRect.origin.y + (firstRect.size.height * 0.7))) { // second entity was actually on top.... secondGameObject.didLandOnEntity.(firstGameObject); } else if (firstRect.origin.x > secondRect.origin.x && firstRect.origin.x < (secondRect.origin.x + secondRect.size.width)) { // Hit from the RIGHT CGRect intersection = CGRectIntersection(firstRect, secondRect); // The NUDGE just offsets either object back to the left or right // After the nudging, they are exactly pressing against each other with no intersection firstGameObject.nudgeToRightOfIntersection(intersection); secondGameObject.nudgeToLeftOfIntersection(intersection); } else if ((firstRect.origin.x + firstRect.size.width) > secondRect.origin.x) { // hit from the LEFT CGRect intersection = CGRectIntersection(firstRect, secondRect); secondGameObject.nudgeToRightOfIntersection(intersection); firstGameObject.nudgeToLeftOfIntersection(intersection); } } } } } I think my collision detection code is pretty close, but obviously I'm doing something a little wrong. I really think it's to do with the way my jumps are checked (I wanted to make sure that a jump could happen from an angle (instead of if the falling player had been at a right angle to the player below). Can someone please help me here? I haven't been able to find many resources on how to do this properly (and thinking like a game developer is new for me). Thanks in advance!

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• What do you need to know to be a world-class master software developer? [closed]

  - by glitch

  I wanted to bring up this question to you folks and see what you think, hopefully advise me on the matter: let's say you had 30 years of learning and practicing software development in front of you, how would you dedicate your time so that you'd get the biggest bang for your buck. What would you both learn and work on to be a world-class software developer that would make a large impact on the industry and leave behind a legacy? I think that most great developers end up being both broad generalists and specialists in one-two areas of interest. I'm thinking Bill Joy, John Carmack, Linus Torvalds, K&R and so on. I'm thinking that perhaps one approach would be to break things down by categories and establish a base minimum of "software development" greatness. I'm thinking: Operating Systems: completely internalize the core concepts of OS, perhaps gain a lot of familiarity with an OSS one such as Linux. Anything from memory management to device drivers has to be complete second nature. Programming Languages: this is one of those topics that imho has to be fully grokked even if it might take many years. I don't think there's quite anything like going through the process of developing your own compiler, understanding language design trade-offs and so on. Programming Language Pragmatics is one of my favorite books actually, I think you want to have that internalized back to back, and that's just the start. You could go significantly deeper, but I think it's time well spent, because it's such a crucial building block. As a subset of that, you want to really understand the different programming paradigms out there. Imperative, declarative, logic, functional and so on. Anything from assembly to LISP should be at the very least comfortable to write in. Contexts: I believe one should have experience working in different contexts to truly be able to appreciate the trade-offs that are being made every day. Embedded, web development, mobile development, UX development, distributed, cloud computing and so on. Hardware: I'm somewhat conflicted about this one. I think you want some understanding of computer architecture at a low level, but I feel like the concepts that will truly matter will be slightly higher level, such as CPU caching / memory hierarchy, ILP, and so on. Networking: we live in a completely network-dependent era. Having a good understanding of the OSI model, knowing how the Web works, how HTTP works and so on is pretty much a pre-requisite these days. Distributed systems: once again, everything's distributed these days, it's getting progressively harder to ignore this reality. Slightly related, perhaps add solid understanding of how browsers work to that, since the world seems to be moving so much to interfacing with everything through a browser. Tools: Have a really broad toolset that you're familiar with, one that continuously expands throughout the years. Communication: I think being a great writer, effective communicator and a phenomenal team player is pretty much a prerequisite for a lot of a software developer's greatness. It can't be overstated. Software engineering: understanding the process of building software, team dynamics, the requirements of the business-side, all the pitfalls. You want to deeply understand where what you're writing fits from the market perspective. The better you understand all of this, the more of your work will actually see the daylight. This is really just a starting list, I'm confident that there's a ton of other material that you need to master. As I mentioned, you most likely end up specializing in a bunch of these areas as you go along, but I was trying to come up with a baseline. Any thoughts, suggestions and words of wisdom from the grizzled veterans out there who would like to share their thoughts and experiences with this? I'd really love to know what you think!

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• Javascript Inheritance Part 2

  - by PhubarBaz

  A while back I wrote about Javascript inheritance, trying to figure out the best and easiest way to do it (http://geekswithblogs.net/PhubarBaz/archive/2010/07/08/javascript-inheritance.aspx). That was 2 years ago and I've learned a lot since then. But only recently have I decided to just leave classical inheritance behind and embrace prototypal inheritance. For most of us, we were trained in classical inheritance, using class hierarchies in a typed language. Unfortunately Javascript doesn't follow that model. It is both classless and typeless, which is hard to fathom for someone who's been using classes the last 20 years. For the last two or three years since I've got into Javascript I've been trying to find the best way to force it into the class model without much success. It's clunky and verbose and hard to understand. I think my biggest problem was that it felt so wrong to add or change object members at run time. Every time I did it I felt like I needed a shower. That's the 20 years of classical inheritance in me. Finally I decided to embrace change and do something different. I decided to use the factory pattern to build objects instead of trying to use inheritance. Javascript was made for the factory pattern because of the way you can construct objects at runtime. In the factory pattern you have a factory function that you call and tell it to give you a certain type of object back. The factory function takes care of constructing the object to your specification. Here's an example. Say we want to have some shape objects and they have common attributes like id and area that we want to depend on in other parts of your application. So first thing to do is create a factory object and give it a factory method to create an abstract shape object. The factory method builds the object then returns it. var shapeFactory = { getShape: function(id){ var shape = { id: id, area: function() { throw "Not implemented"; } }; return shape; }}; Now we can add another factory method to get a rectangle. It calls the getShape() method first and then adds an implementation to it. getRectangle: function(id, width, height){ var rect = this.getShape(id); rect.width = width; rect.height = height; rect.area = function() { return this.width * this.height; }; return rect;} That's pretty simple right? No worrying about hooking up prototypes and calling base constructors or any of that crap I used to do. Now let's create a factory method to get a cuboid (rectangular cube). The cuboid object will extend the rectangle object. To get the area we will call into the base object's area method and then multiply that by the depth. getCuboid: function(id, width, height, depth){ var cuboid = this.getRectangle(id, width, height); cuboid.depth = depth; var baseArea = cuboid.area; cuboid.area = function() { var a = baseArea.call(this); return a * this.depth; } return cuboid;} See how we called the area method in the base object? First we save it off in a variable then we implement our own area method and use call() to call the base function. For me this is a lot cleaner and easier than trying to emulate class hierarchies in Javascript.

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• Changing the Operating System with only Ubuntu installed

  - by Games Brainiac

  I really wanted to dive into the world of Open Source operating systems, so I downloaded the latest version of Ubuntu (13.10), and installed it on a clean(no operating system installed, absolutely nothing) Lenovo ThinkPad machine. After a few days, I wanted to try out a different Operating System (Elementary OS). I downloaded the ISO file, burned it to a USB, tested that the USB booted from a different computer (I have 2, one is the Lenovo, the other a HP). I was able to get the bootscreen, and everything worked like a charm after I set the BIOS to boot from USB Disk Drive instead of HD. After this, I went back to Lenovo, and tried to open up the boot menu, by pressing F12, so that I could load from a temporary device. To my surprise, nothing but the HD was listed. There was no Optical Drive, No USB Drive, absolutely nothing. So, I thought that these devices were probably disabled. So I went into my BIOS and checked to see what was the case. I saw that all my devices were enabled. USB and all the other devices such as network cable and the rest were all enabled. So, I thought this probably had something to do wit UEFI and Legacy Boot options. So, I made sure that both were enabled. This did not solve the problem either. Again, I got nothing but the option to boot from my Hard Disk. I thought the USB had to be at fault. I tried different ports, but to no avail. Next, I tried with a Live CD, which had Ubuntu on it. This failed too. I simply could not boot from anything other than my hard disk. Okay, so at this point, I was pretty desperate, so I installed Boot-Repair through: sudo add-apt-repository ppa:yannubuntu/boot-repair sudo apt-get update sudo apt-get install boot-repair What this did is lead me to GRUB. Ideally, its just a screen that gives me the option to load from Ubuntu or Advanced Settings. The Advanced settings had nothing but Ubuntu options in it. So, I kept on pressing ESC and that led me to the the grub console, and thats where I am right now with my Lenovo. I've also tried updating the BIOS, but Lenovo only has packages for Red Hat and Windows. So, a dead end there too. Right now, I need to know if there is any way that I can just delete everything from my Lenovo? I want to revert it back to its blank factory condition. How can I achieve this? I have tried to elaborate my problem as best I could. If there is any important information that I've missed out, please do not hesitate to leave a comment. I would have included some screen shots, but BIOS screen shots are a little hard to manage. However, I can provide a camera Image of the boot screen if needed (doing that as we speak).

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• Hosted Monitoring

  - by Grant Fritchey

  The concept of using services to take the place of writing a lot of your own code goes way, way back in computing history. The fundamentals of the concept go back to the dawn of computing with places like IBM hosting time-shares for computing power that you could rent for short periods of time. But things really took off with the building of the Web. Now, all the growth with virtual machines, hosted machines, hosted services from vendors like Amazon and Microsoft, the need to keep all of your software locally on physical boxes is just going the way of the dodo. There will likely always be some pieces of software that you keep on machines on your property or on your person, but the concept of keeping fundamental services locally is going away. As someone put it to me once, if you were starting a business right now, would you bother setting up an Exchange server to manage your email or would you just go to one of the external mail services for everything? For most of us (who are not Exchange admins) the answer is pretty easy. With all this momentum to having external services manage more and more of the infrastructure that’s not business unique, why would you burn up a server and license instance setting up monitoring for your SQL Servers? Of course, some of you are dealing with hyper-sensitive data that might require, through law or treaty, that you lock it down and never expose it to the intertubes, but most of us are not. So, what if someone else took on the basic hassle of setting up monitoring on your systems? That’s what we’re working on here at Red Gate. Right now it’s a private test, but we’re growing it and developing it and it’ll be going to a public beta, probably (hopefully) this year. I’m running it on my machines right now. The concept is pretty simple. You put a relay on your server, poke a hole in your firewall for it, and we start monitoring your server using SQL Monitor. It’s actually shocking how easy it is to get going. You still have to adjust your alerting thresholds, but that’s a standard part of alerting. Your pain threshold and my pain threshold for any given alert may be different. But from there, we do all the heavy lifting, keeping your data online and available, providing you with access to the information about how your servers are behaving, everything. Maybe it’s just me, but I’m really excited by this. I think we’re getting to a place where we can really help the small and medium sized businesses get a monitoring solution in place, quickly and easily. All you crazy busy, and possibly accidental, DBAs and system admins finally can set up monitoring without taking all the time to configure systems, run installs, and all the rest. You just have to tweak your alerts and you’re ready to run. If you are interested in checking it out, you can apply for the closed beta through the Monitor web page.

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• High Resolution Timeouts

  - by user12607257

  The default resolution of application timers and timeouts is now 1 msec in Solaris 11.1, down from 10 msec in previous releases. This improves out-of-the-box performance of polling and event based applications, such as ticker applications, and even the Oracle rdbms log writer. More on that in a moment. As a simple example, the poll() system call takes a timeout argument in units of msec: System Calls poll(2) NAME poll - input/output multiplexing SYNOPSIS int poll(struct pollfd fds[], nfds_t nfds, int timeout); In Solaris 11, a call to poll(NULL,0,1) returns in 10 msec, because even though a 1 msec interval is requested, the implementation rounds to the system clock resolution of 10 msec. In Solaris 11.1, this call returns in 1 msec. In specification lawyer terms, the resolution of CLOCK_REALTIME, introduced by POSIX.1b real time extensions, is now 1 msec. The function clock_getres(CLOCK_REALTIME,&res) returns 1 msec, and any library calls whose man page explicitly mention CLOCK_REALTIME, such as nanosleep(), are subject to the new resolution. Additionally, many legacy functions that pre-date POSIX.1b and do not explicitly mention a clock domain, such as poll(), are subject to the new resolution. Here is a fairly comprehensive list: nanosleep pthread_mutex_timedlock pthread_mutex_reltimedlock_np pthread_rwlock_timedrdlock pthread_rwlock_reltimedrdlock_np pthread_rwlock_timedwrlock pthread_rwlock_reltimedwrlock_np mq_timedreceive mq_reltimedreceive_np mq_timedsend mq_reltimedsend_np sem_timedwait sem_reltimedwait_np poll select pselect _lwp_cond_timedwait _lwp_cond_reltimedwait semtimedop sigtimedwait aiowait aio_waitn aio_suspend port_get port_getn cond_timedwait cond_reltimedwait setitimer (ITIMER_REAL) misc rpc calls, misc ldap calls This change in resolution was made feasible because we made the implementation of timeouts more efficient a few years back when we re-architected the callout subsystem of Solaris. Previously, timeouts were tested and expired by the kernel's clock thread which ran 100 times per second, yielding a resolution of 10 msec. This did not scale, as timeouts could be posted by every CPU, but were expired by only a single thread. The resolution could be changed by setting hires_tick=1 in /etc/system, but this caused the clock thread to run at 1000 Hz, which made the potential scalability problem worse. Given enough CPUs posting enough timeouts, the clock thread could be a performance bottleneck. We fixed that by re-implementing the timeout as a per-CPU timer interrupt (using the cyclic subsystem, for those familiar with Solaris internals). This decoupled the clock thread frequency from timeout resolution, and allowed us to improve default timeout resolution without adding CPU overhead in the clock thread. Here are some exceptions for which the default resolution is still 10 msec. The thread scheduler's time quantum is 10 msec by default, because preemption is driven by the clock thread (plus helper threads for scalability). See for example dispadmin, priocntl, fx_dptbl, rt_dptbl, and ts_dptbl. This may be changed using hires_tick. The resolution of the clock_t data type, primarily used in DDI functions, is 10 msec. It may be changed using hires_tick. These functions are only used by developers writing kernel modules. A few functions that pre-date POSIX CLOCK_REALTIME mention _SC_CLK_TCK, CLK_TCK, "system clock", or no clock domain. These functions are still driven by the clock thread, and their resolution is 10 msec. They include alarm, pcsample, times, clock, and setitimer for ITIMER_VIRTUAL and ITIMER_PROF. Their resolution may be changed using hires_tick. Now back to the database. How does this help the Oracle log writer? Foreground processes post a redo record to the log writer, which releases them after the redo has committed. When a large number of foregrounds are waiting, the release step can slow down the log writer, so under heavy load, the foregrounds switch to a mode where they poll for completion. This scales better because every foreground can poll independently, but at the cost of waiting the minimum polling interval. That was 10 msec, but is now 1 msec in Solaris 11.1, so the foregrounds process transactions faster under load. Pretty cool.

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• How to reduce iOS AVPlayer start delay

  - by Bernt Habermeier

  Note, for the below question: All assets are local on the device -- no network streaming is taking place. The videos contain audio tracks. I'm working on an iOS application that requires playing video files with minimum delay to start the video clip in question. Unfortunately we do not know what specific video clip is next until we actually need to start it up. Specifically: When one video clip is playing, we will know what the next set of (roughly) 10 video clips are, but we don't know which one exactly, until it comes time to 'immediately' play the next clip. What I've done to look at actual start delays is to call addBoundaryTimeObserverForTimes on the video player, with a time period of one millisecond to see when the video actually started to play, and I take the difference of that time stamp with the first place in the code that indicates which asset to start playing. From what I've seen thus-far, I have found that using the combination of AVAsset loading, and then creating an AVPlayerItem from that once it's ready, and then waiting for AVPlayerStatusReadyToPlay before I call play, tends to take between 1 and 3 seconds to start the clip. I've since switched to what I think is roughly equivalent: calling [AVPlayerItem playerItemWithURL:] and waiting for AVPlayerItemStatusReadyToPlay to play. Roughly same performance. One thing I'm observing is that the first AVPlayer item load is slower than the rest. Seems one idea is to pre-flight the AVPlayer with a short / empty asset before trying to play the first video might be of good general practice. [http://stackoverflow.com/questions/900461/slow-start-for-avaudioplayer-the-first-time-a-sound-is-played] I'd love to get the video start times down as much as possible, and have some ideas of things to experiment with, but would like some guidance from anyone that might be able to help. Update: idea 7, below, as-implemented yields switching times of around 500 ms. This is an improvement, but it it'd be nice to get this even faster. Idea 1: Use N AVPlayers (won't work) Using ~ 10 AVPPlayer objects and start-and-pause all ~ 10 clips, and once we know which one we really need, switch to, and un-pause the correct AVPlayer, and start all over again for the next cycle. I don't think this works, because I've read there is roughly a limit of 4 active AVPlayer's in iOS. There was someone asking about this on StackOverflow here, and found out about the 4 AVPlayer limit: fast-switching-between-videos-using-avfoundation Idea 2: Use AVQueuePlayer (won't work) I don't believe that shoving 10 AVPlayerItems into an AVQueuePlayer would pre-load them all for seamless start. AVQueuePlayer is a queue, and I think it really only makes the next video in the queue ready for immediate playback. I don't know which one out of ~10 videos we do want to play back, until it's time to start that one. ios-avplayer-video-preloading Idea 3: Load, Play, and retain AVPlayerItems in background (not 100% sure yet -- but not looking good) I'm looking at if there is any benefit to load and play the first second of each video clip in the background (suppress video and audio output), and keep a reference to each AVPlayerItem, and when we know which item needs to be played for real, swap that one in, and swap the background AVPlayer with the active one. Rinse and Repeat. The theory would be that recently played AVPlayer/AVPlayerItem's may still hold some prepared resources which would make subsequent playback faster. So far, I have not seen benefits from this, but I might not have the AVPlayerLayer setup correctly for the background. I doubt this will really improve things from what I've seen. Idea 4: Use a different file format -- maybe one that is faster to load? I'm currently using .m4v's (video-MPEG4) H.264 format. I have not played around with other formats, but it may well be that some formats are faster to decode / get ready than others. Possible still using video-MPEG4 but with a different codec, or maybe quicktime? Maybe a lossless video format where decoding / setup is faster? Idea 5: Combination of lossless video format + AVQueuePlayer If there is a video format that is fast to load, but maybe where the file size is insane, one idea might be to pre-prepare the first 10 seconds of each video clip with a version that is boated but faster to load, but back that up with an asset that is encoded in H.264. Use an AVQueuePlayer, and add the first 10 seconds in the uncompressed file format, and follow that up with one that is in H.264 which gets up to 10 seconds of prepare/preload time. So I'd get 'the best' of both worlds: fast start times, but also benefits from a more compact format. Idea 6: Use a non-standard AVPlayer / write my own / use someone else's Given my needs, maybe I can't use AVPlayer, but have to resort to AVAssetReader, and decode the first few seconds (possibly write raw file to disk), and when it comes to playback, make use of the raw format to play it back fast. Seems like a huge project to me, and if I go about it in a naive way, it's unclear / unlikely to even work better. Each decoded and uncompressed video frame is 2.25 MB. Naively speaking -- if we go with ~ 30 fps for the video, I'd end up with ~60 MB/s read-from-disk requirement, which is probably impossible / pushing it. Obviously we'd have to do some level of image compression (perhaps native openGL/es compression formats via PVRTC)... but that's kind crazy. Maybe there is a library out there that I can use? Idea 7: Combine everything into a single movie asset, and seekToTime One idea that might be easier than some of the above, is to combine everything into a single movie, and use seekToTime. The thing is that we'd be jumping all around the place. Essentially random access into the movie. I think this may actually work out okay: avplayer-movie-playing-lag-in-ios5 Which approach do you think would be best? So far, I've not made that much progress in terms of reducing the lag.

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• Quick guide to Oracle IRM 11g: Configuring SSL

  - by Simon Thorpe

  Quick guide to Oracle IRM 11g index So far in this guide we have an IRM Server up and running, however I skipped over SSL configuration in the previous article because I wanted to focus in more detail now. You can, if you wish, not bother with setting up SSL, but considering this is a security technology it is worthwhile doing. Contents Setting up a one way, self signed SSL certificate in WebLogic Setting up an official SSL certificate in Apache 2.x Configuring Apache to proxy traffic to the IRM server There are two common scenarios in which an Oracle IRM server is configured. For a development or evaluation system, people usually communicate directly to the WebLogic Server running the IRM service. However in a production environment and for some proof of concept evaluations that require a setup reflecting a production system, the traffic to the IRM server travels via a web server proxy, commonly Apache. In this guide we are building an Oracle Enterprise Linux based IRM service and this article will go over the configuration of SSL in WebLogic and also in Apache. Like in the past articles, we are going to use two host names in the configuration below,irm.company.com will refer to the public Apache server irm.company.internal will refer to the internal WebLogic IRM server Setting up a one way, self signed SSL certificate in WebLogic First lets look at creating just a simple self signed SSL certificate to be used in WebLogic. This is a quick and easy way to get SSL working in your environment, however the downside is that no browsers are going to trust this certificate you create and you'll need to manually install the certificate onto any machine's communicating with the server. This is fine for development or when you have only a few users evaluating the system, but for any significant use it's usually better to have a fully trusted certificate in use and I explain that in the next section. But for now lets go through creating, installing and testing a self signed certificate. We use a library in Java to create the certificates, open a console and running the following commands. Note you should choose your own secure passwords whenever you see password below. [oracle@irm /] source /oracle/middleware/wlserver_10.3/server/bin/setWLSEnv.sh [oracle@irm /] cd /oracle/middleware/user_projects/domains/irm_domain/config/fmwconfig/ [oracle@irm /] java utils.CertGen -selfsigned -certfile MyOwnSelfCA.cer -keyfile MyOwnSelfKey.key -keyfilepass password -cn "irm.oracle.demo" [oracle@irm /] java utils.ImportPrivateKey -keystore MyOwnIdentityStore.jks -storepass password -keypass password -alias trustself -certfile MyOwnSelfCA.cer.pem -keyfile MyOwnSelfKey.key.pem -keyfilepass password [oracle@irm /] keytool -import -trustcacerts -alias trustself -keystore TrustMyOwnSelf.jks -file MyOwnSelfCA.cer.der -keyalg RSA We now have two Java Key Stores, MyOwnIdentityStore.jks and TrustMyOwnSelf.jks. These contain keys and certificates which we will use in WebLogic Server. Now we need to tell the IRM server to use these stores when setting up SSL connections for incoming requests. Make sure the Admin server is running and login into the WebLogic Console at http://irm.company.intranet:7001/console and do the following; In the menu on the left, select the + next to Environment to expose the submenu, then click on Servers. You will see two servers in the list, AdminServer(admin) and IRM_server1. If the IRM server is running, shut it down either by hitting CONTROL + C in the console window it was started from, or you can switch to the CONTROL tab, select IRM_server1 and then select the Shutdown menu and then Force Shutdown Now. In the Configuration tab select IRM_server1 and switch to the Keystores tab. By default WebLogic Server uses it's own demo identity and trust. We are now going to switch to the self signed one's we've just created. So select the Change button and switch to Custom Identity and Custom Trust and hit save. Now we have to complete the resulting fields, the setting's i've used in my evaluation server are below. IdentityCustom Identity Keystore: /oracle/middleware/user_projects/domains/irm_domain/config/fmwconfig/MyOwnIdentityStore.jks Custom Identity Keystore Type: JKS Custom Identity Keystore Passphrase: password Confirm Custom Identity Keystore Passphrase: password TrustCustom Trust Keystore: /oracle/middleware/user_projects/domains/irm_domain/config/fmwconfig/TrustMyOwnSelf.jks Custom Trust Keystore Type: JKS Custom Trust Keystore Passphrase: password Confirm Custom Trust Keystore Passphrase: password Now click on the SSL tab for the IRM_server1 and enter in the alias and passphrase, in my demo here the details are; IdentityPrivate Key Alias: trustself Private Key Passphrase: password Confirm Private Key Passphrase: password And hit save. Now lets test a connection to the IRM server over HTTPS using SSL. Go back to a console window and start the IRM server, a quick reminder on how to do this is... [oracle@irm /] cd /oracle/middleware/user_projects/domains/irm_domain/bin [oracle@irm /] ./startManagedWeblogic IRM_server1 Once running, open a browser and head to the SSL port of the server. By default the IRM server will be listening on the URL https://irm.company.intranet:16101/irm_rights. Note in the example image on the right the port is 7002 because it's a system that has the IRM services installed on the Admin server, this isn't typical (or advisable). Your system is going to have a separate managed server which will be listening on port 16101. Once you open this address you will notice that your browser is going to complain that the server certificate is untrusted. The images on the right show how Firefox displays this error. You are going to be prompted every time you create a new SSL session with the server, both from the browser and more annoyingly from the IRM Desktop. If you plan on always using a self signed certificate, it is worth adding it to the Windows certificate store so that when you are accessing sealed content you do not keep being informed this certificate is not trusted. Follow these instructions (which are for Internet Explorer 8, they may vary for your version of IE.) Start Internet Explorer and open the URL to your IRM server over SSL, e.g. https://irm.company.intranet:16101/irm_rights. IE will complain that about the certificate, click on Continue to this website (not recommended). From the IE Tools menu select Internet Options and from the resulting dialog select Security and then click on Trusted Sites and then the Sites button. Add to the list of trusted sites a URL which mates the server you are accessing, e.g. https://irm.company.intranet/ and select OK. Now refresh the page you were accessing and next to the URL you should see a red cross and the words Certificate Error. Click on this button and select View Certificates. You will now see a dialog with the details of the self signed certificate and the Install Certificate... button should be enabled. Click on this to start the wizard. Click next and you'll be asked where you should install the certificate. Change the option to Place all certificates in the following store. Select browse and choose the Trusted Root Certification Authorities location and hit OK. You'll then be prompted to install the certificate and answer yes. You also need to import the root signed certificate into the same location, so once again select the red Certificate Error option and this time when viewing the certificate, switch to the Certification Path tab and you should see a CertGenCAB certificate. Select this and then click on View Certificate and go through the same process as above to import the certificate into the store. Finally close all instances of the IE browser and re-access the IRM server URL again, this time you should not receive any errors. Setting up an official SSL certificate in Apache 2.x At this point we now have an IRM server that you can communicate with over SSL. However this certificate isn't trusted by any browser because it's path of trust doesn't end in a recognized certificate authority (CA). Also you are communicating directly to the WebLogic Server over a non standard SSL port, 16101. In a production environment it is common to have another device handle the initial public internet traffic and then proxy this to the WebLogic server. The diagram below shows a very simplified view of this type of deployment. What i'm going to walk through next is configuring Apache to proxy traffic to a WebLogic server and also to use a real SSL certificate from an official CA. First step is to configure Apache to handle incoming requests over SSL. In this guide I am configuring the IRM service in Oracle Enterprise Linux 5 update 3 and Apache 2.2.3 which came with OpenSSL and mod_ssl components. Before I purchase an SSL certificate, I need to generate a certificate request from the server. Oracle.com uses Verisign and for my own personal needs I use cheaper certificates from GoDaddy. The following instructions are specific to Apache, but there are many references out there for other web servers. For Apache I have OpenSSL and the commands are; [oracle@irm /] cd /usr/bin [oracle@irm bin] openssl genrsa -des3 -out irm-apache-server.key 2048 Generating RSA private key, 2048 bit long modulus ............................+++ .........+++ e is 65537 (0x10001) Enter pass phrase for irm-apache-server.key: Verifying - Enter pass phrase for irm-apache-server.key: [oracle@irm bin] openssl req -new -key irm-apache-server.key -out irm-apache-server.csr Enter pass phrase for irm-apache-server.key: You are about to be asked to enter information that will be incorporated into your certificate request. What you are about to enter is what is called a Distinguished Name or a DN. There are quite a few fields but you can leave some blank For some fields there will be a default value, If you enter '.', the field will be left blank. ----- Country Name (2 letter code) [GB]:US State or Province Name (full name) [Berkshire]:CA Locality Name (eg, city) [Newbury]:San Francisco Organization Name (eg, company) [My Company Ltd]:Oracle Organizational Unit Name (eg, section) []:Security Common Name (eg, your name or your server's hostname) []:irm.company.com Email Address []:[email protected] Please enter the following 'extra' attributes to be sent with your certificate request A challenge password []:testing An optional company name []: You must make sure to remember the pass phrase you used in the initial key generation, you will need this when later configuring Apache. In the /usr/bin directory there are now two new files. The irm-apache-server.csr contains our certificate request and is what you cut and paste, or upload, to your certificate authority when you purchase and validate your SSL certificate. In response you will typically get two files. Your server certificate and another certificate file that will likely contain a set of certificates from your CA which validate your certificate's trust. Next we need to configure Apache to use these files. Typically there is an ssl.conf file which is where all the SSL configuration is done. On my Oracle Enterprise Linux server this file is located in /etc/httpd/conf.d/ssl.conf and i've added the following lines. <VirtualHost irm.company.com> # Setup SSL for irm.company.com ServerName irm.company.com SSLEngine On SSLCertificateFile /oracle/secure/irm.company.com.crt SSLCertificateKeyFile /oracle/secure/irm.company.com.key SSLCertificateChainFile /oracle/secure/gd_bundle.crt </VirtualHost> Restarting Apache (apachectl restart) and I can now attempt to connect to the Apache server in a web browser, https://irm.company.com/. If all is configured correctly I should now see an Apache test page delivered to me over HTTPS. Configuring Apache to proxy traffic to the IRM server Final piece in setting up SSL is to have Apache proxy requests for the IRM server but do so securely. So the requests to Apache will be over HTTPS using a legitimate certificate, but we can also configure Apache to proxy these requests internally across to the IRM server using SSL with the self signed certificate we generated at the start of this article. To do this proxying we use the WebLogic Web Server plugin for Apache which you can download here from Oracle. Download the zip file and extract onto the server. The file extraction reveals a set of zip files, each one specific to a supported web server. In my instance I am using Apache 2.2 32bit on an Oracle Enterprise Linux, 64 bit server. If you are not sure what version your Apache server is, run the command /usr/sbin/httpd -V and you'll see version and it its 32 or 64 bit. Mine is a 32bit server so I need to extract the file WLSPlugin1.1-Apache2.2-linux32-x86.zip. The from the resulting lib folder copy the file mod_wl.so into /usr/lib/httpd/modules/. First we want to test that the plug in will work for regular HTTP traffic. Edit the httpd.conf for Apache and add the following section at the bottom. LoadModule weblogic_module modules/mod_wl.so <IfModule mod_weblogic.c>    WebLogicHost irm.company.internal    WebLogicPort 16100    WLLogFile /tmp/wl-proxy.log </IfModule> <Location /irm_rights>    SetHandler weblogic-handler </Location> <Location /irm_desktop>    SetHandler weblogic-handler </Location> <Location /irm_sealing>    SetHandler weblogic-handler </Location> <Location /irm_services>    SetHandler weblogic-handler </Location> Now restart Apache again (apachectl restart) and now open a browser to http://irm.company.com/irm_rights. Apache will proxy the HTTP traffic from the port 80 of your Apache server to the IRM service listening on port 16100 of the WebLogic Managed server. Note above I have included all four of the Locations you might wish to proxy. http://irm.company.internalirm_rights is the URL to the management website, /irm_desktop is the URL used for the IRM Desktop to communicate. irm_sealing is for web services based document sealing and irm_services is for IRM server web services. The last two are typically only used when you have the IRM server integrated with another application and it is unlikely you'd be accessing these resources from the public facing Apache server. However, just in case, i've mentioned them above. Now let's enable SSL communication from Apache to WebLogic. In the ZIP file we extracted were some more modules we need to copy into the Apache folder. Looking back in the lib that we extracted, there are some more files. Copy the following into the /usr/lib/httpd/modules/ folder. libwlssl.so libnnz11.so libclntsh.so.11.1 Now the documentation states that should only need to do this, but I found that I also needed to create an environment variable called LD_LIBRARY_PATH and point this to the folder /usr/lib/httpd/modules/. If I didn't do this, starting Apache with the WebLogic module configured to SSL would throw the error. [crit] (20014)Internal error: WL SSL Init failed for server: (null) on 0 So I had to edit the file /etc/profile and add the following lines at the bottom. You may already have the LD_LIBRARY_PATH variable defined, therefore simply add this path to it. LD_LIBRARY_PATH=/usr/lib/httpd/modules/ export LD_LIBRARY_PATH Now the WebLogic plug in uses an Oracle Wallet to store the required certificates.You'll need to copy the self signed certificate from the IRM server over to the Apache server. Copy over the MyOwnSelfCA.cer.der into the same folder where you are storing your public certificates, in my example this is /oracle/secure. It's worth mentioning these files should ONLY be readable by root (the user Apache runs as). Now lets create an Oracle Wallet and import the self signed certificate from the IRM server. The file orapki was included in the bin folder of the Apache 1.1 plugin zip you extracted. orapki wallet create -wallet /oracle/secure/my-wallet -auto_login_only orapki wallet add -wallet /oracle/secure/my-wallet -trusted_cert -cert MyOwnSelfCA.cer.der -auto_login_only Finally change the httpd.conf to reflect that we want the WebLogic Apache plug-in to use HTTPS/SSL and not just plain HTTP. <IfModule mod_weblogic.c>    WebLogicHost irm.company.internal    WebLogicPort 16101    SecureProxy ON    WLSSLWallet /oracle/secure/my-wallet    WLLogFile /tmp/wl-proxy.log </IfModule> Then restart Apache once more and you can go back to the browser to test the communication. Opening the URL https://irm.company.com/irm_rights will proxy your request to the WebLogic server at https://irm.company.internal:16101/irm_rights. At this point you have a fully functional Oracle IRM service, the next step is to create a sealed document and test the entire system.

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• Quick guide to Oracle IRM 11g: Server configuration

  - by Simon Thorpe

  Quick guide to Oracle IRM 11g index Welcome to the second article in this quick quide to Oracle IRM 11g. Hopefully you've just finished the first article which takes you through deploying the software onto a Linux server. This article walks you through the configuration of this new service and contains a subset of information from the official documentation and is focused on installing the server on Oracle Enterprise Linux. If you are planning to deploy on a non-Linux platform, you will need to reference the documentation for platform specific information. Contents Introduction Create IRM WebLogic Domain Starting the Admin Server and initial configuration Introduction In the previous article the database was prepared, the WebLogic Application Server installed and the files required for an IRM server installed. But we don't actually have a configured system yet. We need to now create a WebLogic Domain in which the IRM server will run, then configure some of the settings and crypography so that we can create a context and be ready to seal some content and test it all works. This article doesn't cover the configuration of SSL communication from client to server. This is quite a big topic and a separate article has been dedicated for this area. In these articles I also use the hostname, irm.company.internal to reference the IRM server and later on use the hostname irm.company.com in reference to the public facing service. Create IRM WebLogic Domain First step is creating the WebLogic domain, in a console switch to the newly created IRM installation folder as shown below and we will run the domain configuration wizard. [oracle@irm /]$ cd /oracle/middleware/Oracle_IRM/common/bin [oracle@irm bin]$ ./config.sh First thing the wizard will ask is if you wish to create a new or extend an existing domain. This guide is creating a standalone system so you should select to create a new domain. Next step is to choose what technologies from the Oracle ECM Suite you wish this domain to host. You are only interested in selecting the option "Oracle Information Rights Management". When you select this check box you will notice that it also selects "Oracle Enterprise Manager" and "Oracle JRF" as these are dependencies of the IRM server. You then need to specify where you wish to place the domain files. I usually just change the domain name from base_domain or irm_domain and leave the others with their defaults. Now the domain will have a single user initially and by default this user is called "weblogic". I usually change this account name to "sysadmin" or "administrator", but in this guide lets just accept the default. With respects to the next dialog, again for eval or dev reasons, leave the server startup mode as development. The JDK should also be automatically detected. We now need to provide details of the database. This guide is using the Oracle 11gR2 database and the settings I used can be seen in the image to the right. There is a lot of configuration that can now be done for the admin server, any managed servers and where the deployments reside. In this guide I am leaving all of these to their defaults so do not check any of the boxes. However I will on this blog be detailing later how you can go back and setup things such as automated startup of an IRM server which require changes to these default settings. But for now, lets leave it all alone and just click next. Now we are ready to install. Note that from this dialog you can scroll the left window and see there are going to be two servers created from the defaults. The AdminServer which is where you modify settings for the WebLogic Server and also hosts the Oracle Enterprise Manager for IRM which allows to monitor the IRM service performance and also make service related settings (which we shortly do below) and the IRM_server1 which hosts the actual IRM services themselves. So go right ahead and hit create, the process is pretty quick and usually under 10 minutes. When the domain creation ends, it will give you the URL to the admin server. It's worth noting this down and the URL is usually; http://irm.company.internal:7001 Starting the Admin Server and initial configuration First thing to do is to start the WebLogic Admin server and review the initial IRM server settings. In this guide we are going to run the Admin server and IRM server in console windows, in another article I will discuss running these as background services. So for now, start a console and run the Admin server by doing the following. cd /oracle/middleware/user_projects/domains/irm_domain/ ./startWebLogic.sh Wait for the server to start, you are looking for the following line to be reported in the console window. <BEA-00360><Server started in RUNNING mode> First step is configuring the IRM service via Enterprise Manager. Now that the Admin server is running you can point a browser at http://irm.company.internal:7001/em. Login with the username and password you supplied when you created the domain. In Enterprise Manager the IRM service administrator is able to make server wide configuration. However finding where to access the pages with these settings can be a bit of a challenge. After logging in on the left you'll see a tree containing elements of the Enterprise Manager farm Farm_irm_domain. Open up Content Management, then Information Rights Management and finally select the IRM node. On the right then select the IRM menu item, navigate to the Administration section and now we have four options, for now, we are just going to look at General Settings. The image on the right proves that a picture is worth a thousand words (or 113 in this case). The General Settings page allows you to set the cryptographic algorithms used for protecting sealed content. Unless you have a burning need to increase the key lengths or you need to comply to a regulation or government mandate, AES192 is a good start. You can change this later on without worry. The most important setting here we need to make is the Server URL. In this blog article I go over why this URL is so important, basically every single piece of content you protect with Oracle IRM is going to have this URL embedded in it, so if it's wrong or unresolvable, then nobody can open the secured documents. Note that in our environment we have yet to do any SSL configuration of the service. If you intend to build a server without SSL, then use http as the protocol instead of https. But I would recommend using SSL and setting this up is described in the next article. I would also probably up the device count from 1 to 3. This means that any user can retrieve rights to access content onto 3 computers at any one time. The default of 1 doesn't really make sense in development, evaluation nor even production environments and my experience is that 3 is a better number. Next step is to create the keystore for the IRM server. When a classification (called a context) is created, Oracle IRM generates a unique set of symmetric keys which are used to secure the content itself. These keys are then encrypted with a set of "wrapper" asymmetric cryptography keys which are stored externally to the server either in a Java Key Store or a HSM. These keys need to be generated and the following shows my commands and the resulting output. I have greyed out the responses from the commands so you can see the input a little easier. [oracle@irmsrv ~]$ cd /oracle/middleware/wlserver_10.3/server/bin/ [oracle@irmsrv bin]$ ./setWLSEnv.sh CLASSPATH=/oracle/middleware/patch_wls1033/profiles/default/sys_manifest_classpath/weblogic_patch.jar:/oracle/middleware/patch_ocp353/profiles/default/sys_manifest_classpath/weblogic_patch.jar:/usr/java/jdk1.6.0_18/lib/tools.jar:/oracle/middleware/wlserver_10.3/server/lib/weblogic_sp.jar:/oracle/middleware/wlserver_10.3/server/lib/weblogic.jar:/oracle/middleware/modules/features/weblogic.server.modules_10.3.3.0.jar:/oracle/middleware/wlserver_10.3/server/lib/webservices.jar:/oracle/middleware/modules/org.apache.ant_1.7.1/lib/ant-all.jar:/oracle/middleware/modules/net.sf.antcontrib_1.1.0.0_1-0b2/lib/ant-contrib.jar: PATH=/oracle/middleware/wlserver_10.3/server/bin:/oracle/middleware/modules/org.apache.ant_1.7.1/bin:/usr/java/jdk1.6.0_18/jre/bin:/usr/java/jdk1.6.0_18/bin:/usr/kerberos/bin:/usr/local/bin:/bin:/usr/bin:/home/oracle/bin Your environment has been set. [oracle@irmsrv bin]$ cd /oracle/middleware/user_projects/domains/irm_domain/config/fmwconfig/ [oracle@irmsrv fmwconfig]$ keytool -genkeypair -alias oracle.irm.wrap -keyalg RSA -keysize 2048 -keystore irm.jks Enter keystore password: Re-enter new password: What is your first and last name? [Unknown]: Simon Thorpe What is the name of your organizational unit? [Unknown]: Oracle What is the name of your organization? [Unknown]: Oracle What is the name of your City or Locality? [Unknown]: San Francisco What is the name of your State or Province? [Unknown]: CA What is the two-letter country code for this unit? [Unknown]: US Is CN=Simon Thorpe, OU=Oracle, O=Oracle, L=San Francisco, ST=CA, C=US correct? [no]: yes Enter key password for (RETURN if same as keystore password): At this point we now have an irm.jks in the directory /oracle/middleware/user_projects/domains/irm_domain/config/fmwconfig. The reason we store it here is this folder would be backed up as part of a domain backup. As with any cryptographic technology, DO NOT LOSE THESE KEYS OR THIS KEY STORE. Once you've sealed content against a context, the keys will be wrapped with these keys, lose these keys, and you can't get access to any secured content, pretty important. Now we've got the keys created, we need to go back to the IRM Enterprise Manager and set the location of the key store. Going back to the General Settings page in Enterprise Manager scroll down to Keystore Settings. Leave the type as JKS but change the location to; /oracle/Middleware/user_projects/domains/irm_domain/config/fmwconfig/irm.jks and hit Apply. The final step with regards to the key store is we need to tell the server what the password is for the Java Key Store so that it can be opened and the keys accessed. Once more fire up a console window and run these commands (again i've greyed out the clutter to see the commands easier). You will see dummy passed into the commands, this is because the command asks for a username, but in this instance we don't use one, hence the value dummy is passed and it isn't used. [oracle@irmsrv fmwconfig]$ cd /oracle/middleware/Oracle_IRM/common/bin/ [oracle@irmsrv bin]$ ./wlst.sh ... lots of settings fly by... Welcome to WebLogic Server Administration Scripting Shell Type help() for help on available commands wls:/offline>connect('weblogic','password','t3://irmsrv.us.oracle.com:7001') Connecting to t3://irmsrv.us.oracle.com:7001 with userid weblogic ... Successfully connected to Admin Server 'AdminServer' that belongs to domain 'irm_domain'. Warning: An insecure protocol was used to connect to the server. To ensure on-the-wire security, the SSL port or Admin port should be used instead. wls:/irm_domain/serverConfig>createCred("IRM","keystore:irm.jks","dummy","password") Location changed to domainRuntime tree. This is a read-only tree with DomainMBean as the root. For more help, use help(domainRuntime)wls:/irm_domain/serverConfig>createCred("IRM","key:irm.jks:oracle.irm.wrap","dummy","password") Already in Domain Runtime Tree wls:/irm_domain/serverConfig> At last we are now ready to fire up the IRM server itself. The domain creation created a managed server called IRM_server1 and we need to start this, use the following commands in a new console window. cd /oracle/middleware/user_projects/domains/irm_domain/bin/ ./startManagedWebLogic.sh IRM_server1 This will start up the server in the console, unlike the Admin server, you need to provide the username and password for the service to start. Enter in your weblogic username and password when prompted. You can change this behavior by putting the password into a boot.properties file, read more about this in the WebLogic Server documentation. Once running, wait until you see the line; <Notice><WebLogicServer><BEA-000360><Server started in RUNNING mode> At this point we can now login to the Oracle IRM Management Website at the URL. http://irm.company.internal:1600/irm_rights/ The server is just configured for HTTP at the moment, no SSL involved. Just want to ensure we can get a working system up and running. You should now see a login like the image on the right and you can now login using your weblogic username and password. The next article in this guide goes over adding SSL and now testing your server by actually adding a few users, sealing some content and opening this content as a user.

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