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  • IIS 7 and ASP.NET State Service Configuration

    - by Shawn
    We have 2 web servers load balanced and we wanted to get away from sticky sessions for obvious reasons. Our attempted approach is to use the ASP.NET State service on one of the boxes to store the session state for both. I realize that it's best to have a server dedicated to storing sessions but we don't have the resources for that. I've followed these instructions to no avail. The session still isn't being shared between the two servers. I'm not receiving any errors. I have the same machine key for both servers, and I've set the application ID to a unique value that matches between the two servers. Any suggestions on how I can troubleshoot this issue? Update: I turned on the session state service on my local machine and pointed both servers to the ip address on my local machine and it worked as expected. The session was shared between both servers. This leads me to believe that the problem might be that I'm not using a standalone server as my state service. Perhaps the problem is because I am using the ip address 127.0.0.1 on one server and then using a different ip address on the other server. Unfortunately when I try to use the network ip address as opposed to localhost the connection doesn't seem to work from the host server. Any insight on whether my suspicions are correct would be appreciated.

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  • State management using the Application class in ASP.Net applications

    - by nikolaosk
    I have explained some of the state mechanisms that we have in our disposal for preserving state in ASP.Net applications in various posts in this blog. You can have a look at this post , this post , this post and this one . I have not presented yet an example in using the Application class/object for preserving state within our application. Application state is available globally in an application.The way we access Application State is through the HttpApplication object's Application property. Let...(read more)

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  • Manually start session with specific id / transitioning session cookie between domains

    - by deceze
    My host requires me to use a different domain for SSL secured access (shared SSL), so I need to transition the user session between two domains. One part of the page lives at http://example.com, while the SSL'd part is at https://example.hosting.com. As such I can't set a domain-spanning cookie. What I'm trying to do is to transition the session id over and re-set the cookie like this: http://example.com/normal/page, user clicks link to secure area and goes to: http://example.com/secure/page, which causes a redirect to: https://example.hosting.com/secure/page?sess=ikub..., which resurrects the session and sets a new cookie valid for the domain, then redirects to: https://example.hosting.com/secure/page This works up to the point where the session should be resurrected. I'm doing: function beforeFilter() { ... $this->Session->id($_GET['sess']); $this->Session->activate(); ... } As far as I can tell this should start the session with the given ID. It actually generates a new session ID though and this session is empty, the data is not restored. This is on CakePHP 1.2.4. Do I need to do something else, or is there a better way to do what I'm trying to do?

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  • State pattern: Why doesn't the context class implement or inherit the State abstract interface/class

    - by Ricket
    I'm reading about the State pattern. I have only just begun, so of course I begin by reading the entire Wikipedia article on it. I noticed that both of the examples in the article have some base abstract class or Java interface for a generic State's methods/functions. Then there are some states which inherit from the base and implement those methods/functions in different ways. Then there's a Context class which has a private member of type State and which, at any time, can be equal to an instance of one of the implementations. That context class also implements the same methods, and passes them onto the current state instance, and then has an additional method to change the state (or depending on design I understand the change of state could be a reaction to one of the implemented methods). Why doesn't this context class specifically "extend" or "implement" the generic State base class/interface?

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  • An XEvent a Day (4 of 31) – Querying the Session Definition and Active Session DMV’s

    - by Jonathan Kehayias
    Yesterdays post, Managing Event Sessions , showed how to manage Event Sessions in Extended Events Sessions inside the Extended Events framework in SQL Server. In today's post, we’ll take a look at how to find information about the defined Event Sessions that already exist inside a SQL Server using the Session Definition DMV’s and how to find information about the Active Event Sessions that exist using the Active Session DMV’s. Session Definition DMV’s The Session Definition DMV’s provide information...(read more)

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  • Using both IIS6 and IIS7 with the same SQL State Server

    - by Josef
    We are trying to use new IIS7 (32bit, Classic Mode) webs in addition to our IIS6 webs with one SQL State Server for ASP.NET Session Handling. Unfortunately the number of transactions per seconds in the State Servers spikes (10 times+) as soon as we add the new IIS7 web to the farm. Are there any known issues with the described setup?

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  • In a state machine, is it a good idea to separate states and transitions?

    - by codablank1
    I have implemented a small state machine in this way (in pseudo code): class Input {} class KeyInput inherits Input { public : enum { Key_A, Key_B, ..., } } class GUIInput inherits Input { public : enum { Button_A, Button_B, ..., } } enum Event { NewGame, Quit, OpenOptions, OpenMenu } class BaseState { String name; Event get_event (Input input); void handle (Event e); //event handling function } class Menu inherits BaseState{...} class InGame inherits BaseState{...} class Options inherits BaseState{...} class StateMachine { public : BaseState get_current_state () { return current_state; } void add_state (String name, BaseState state) { statesMap.insert(name, state);} //raise an exception if state not found BaseState get_state (String name) { return statesMap.find(name); } //raise an exception if state or next_state not found void add_transition (Event event, String state_name, String next_state_name) { BaseState state = get_state(state_name); BaseState next_state = get_state(next_state_name); transitionsMap.insert(pair<event, state>, next_state); } //raise exception if couple not found BaseState get_next_state(Event event, BaseState state) { return transitionsMap.find(pair<event, state>); } void handle(Input input) { Event event = current_state.get_event(input) current_state.handle(event); current_state = get_next_state(event, current_state); } private : BaseState current_state; map<String, BaseState> statesMap; //map of all states in the machine //for each couple event/state, this map stores the next state map<pair<Event, BaseState>, BaseState> transitionsMap; } So, before getting the transition, I need to convert the key input or GUI input to the proper event, given the current state; thus the same key 'W' can launch a new game in the 'Menu' state or moving forward a character in the 'InGame' state; Then I get the next state from the transitionsMap and I update the current state Does this configuration seem valid to you ? Is it a good idea to separate states and transitions ? And I have some kind of trouble to represent a 'null state' or a 'null event'; What initial value can I give to the current state and which one should be returned by get_state if it fails ?

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  • NEED your opinion on .net Profile class VS session vars

    - by Ted
    To save trips to sql db in my older apps, I store *dozens of data points about the current user in an array and then store the array in a session. For example, info that might be used repeatedly during user’s session might be stored… Dim a(7) as string a(0) = “FirstName” a(1) = “LastName” a(2) = “Address” a(3) = “Address2” a(4) = “City” a(5) = “State” a(6) = “Zip” session.add(“s_a”, a) *Some apps have an array 100 in size. That is something I learned in my asp classic days. Referencing the correct index can be laborsome and I find it difficult to go back and add another data point in the array grouped with like data. For example, suppose I need to add Middle Initial to the array as a design alteration. Unless I redo the whole index mapping, I have to stick Middle Initial in the next open slot, which might be in the 50s. NOW, I am considering doing something easier to reference each time (eliminating the need to know the index of the value wanted). So I am looking to do this… session.add(“Firstname”, “FirstName”) session.add(“Lastname”, “LastName”) session.add(“Address”, “Address”) etc. BUT, before I do this, I would like some guidance. I am afraid this might be less efficient, even though easier to use. I don’t know if a new session object is created for each data point or if there is only one session object, and I am adding a name/value pair to that object? If I am adding a name/value pair to a single object, that seems like a good idea. Does anyone know? Or is there a more preferred way? Built-in Profile class? Re: Profile class I have an internal debate about scope. It seems that the .net Profile class is good for storing app-SPECIFIC user settings (i.e. style theme, object display properties, user role, etc.) The examples I give are information whose values are selected/edited by the user to customize the application experience. This information is not typically stored/edited elsewhere in the app db. But when you have data that 1) is stored already in the app db and 2) can be altered by other users (in this case: company reps may update client's status, address, etc.), then the persistence of the Profile data may be an issue. In this case, the Profile would need to be reset at the beginning and dropped like a session.abandon at the end of each user's session to prevent reloading info that had since been edited by someone. I believe this is possible, but not sure Currently, I use the session array to store both scopes, app-specific and user-specific data. If my session plan is good, I think I will create a class to set/get values from the session also. I appreciate your thoughts. I would like to know how others have handled this type of situation. Thanks.

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  • iptables rules keep showing up

    - by Omriko
    I just installed an ubuntu precise server, after a few weird communications issues I checked the iptables list and found: Chain INPUT (policy DROP) target prot opt source destination ACCEPT all -- anywhere anywhere ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED ACCEPT tcp -- 10.0.0.0/24 anywhere tcp spts:1024:65535 dpt:ssh state NEW ACCEPT icmp -- anywhere anywhere state NEW ACCEPT icmp -- anywhere anywhere state NEW ACCEPT icmp -- anywhere anywhere state NEW ACCEPT icmp -- anywhere anywhere state NEW DROP tcp -- anywhere anywhere tcp dpt:10520 state NEW DROP udp -- anywhere anywhere udp spts:1:65535 dpt:31337 state NEW DROP udp -- anywhere anywhere udp spts:1:65535 dpt:31338 state NEW DROP udp -- anywhere anywhere udp spts:1:65535 dpt:54320 state NEW DROP udp -- anywhere anywhere udp spts:1:65535 dpt:54321 state NEW DROP tcp -- anywhere anywhere tcp dpt:12345 state NEW DROP tcp -- anywhere anywhere tcp dpt:12346 state NEW DROP tcp -- anywhere anywhere tcp dpt:20034 state NEW DROP tcp -- anywhere anywhere tcp dpt:16600 state NEW DROP tcp -- anywhere anywhere tcp dpt:16660 state NEW DROP tcp -- anywhere anywhere tcp dpt:65000 state NEW DROP udp -- anywhere anywhere udp dpt:34555 state NEW DROP udp -- anywhere anywhere udp dpt:35555 state NEW DROP udp -- anywhere anywhere udp spts:netbios-ns:netbios-dgm dpts:netbios-ns:netbios-dgm state NEW DROP tcp -- anywhere anywhere tcp spts:1024:65535 dpt:netbios-ssn state NEW DROP tcp -- anywhere anywhere tcp spts:1024:65535 dpt:microsoft-ds state NEW DROP udp -- anywhere anywhere udp spt:microsoft-ds dpt:microsoft-ds state NEW DROP udp -- anywhere anywhere udp spts:1024:65535 dpt:microsoft-ds state NEW DROP tcp -- anywhere anywhere tcp spts:1024:65535 dpt:loc-srv state NEW DROP tcp -- anywhere anywhere tcp spts:1024:65535 dpt:5000 state NEW DROP tcp -- anywhere anywhere tcp spts:1024:65535 dpts:1025:1029 state NEW DROP udp -- anywhere anywhere udp spts:1:65535 dpt:loc-srv state NEW ACCEPT tcp -- anywhere anywhere tcp spts:1024:65535 dpt:28082 state NEW DROP all -- anywhere anywhere state NEW Chain FORWARD (policy DROP) target prot opt source destination Chain OUTPUT (policy DROP) target prot opt source destination ACCEPT all -- anywhere anywhere ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED ACCEPT tcp -- anywhere anywhere tcp spts:tcpmux:65535 dpts:tcpmux:65535 state NEW ACCEPT udp -- anywhere anywhere udp dpts:1:65535 state NEW ACCEPT icmp -- anywhere anywhere state NEW ACCEPT tcp -- anywhere anywhere tcp spts:1024:65535 dpt:28082 state NEW DROP all -- anywhere anywhere state NEW I tried to wipe the rules, I disabled UFW, Ive rewritten and saved iptables rules according to this guide, but every minute or so the old rules return.... I checked crontab for scheduled tasks, there is nothing in there but still these rules appear every minute... please help!

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  • Designing a state machine in C++

    - by skyeagle
    I have a little problem that involves modelling a state machine. I have managed to do a little bit of knowledge engineering and 'reverse engineer' a set of primitive deterministic rules that determine state as well as state transitions. I would like to know what the best practises are regarding: How to rigorously test my states and state transitions to make sure that the system cannot end up in an undeetermined state. How to enforce state transition requirements (for example, it should be impossible to go directly from stateFoo to StateFooBar, i.e. to embue each state with 'knowlege' about the states it can transition to. Ideally, I would like to use clean, pattern based design, with templates wherever possible. I do need somewhere to start though and I would be grateful for any pointers (no pun intended), that are sent my way.

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  • How Can I switch the session storage according to the client on Ruby on Rails 2.3.5

    - by mojalin
    Hi! I have a question about sessions on ruby-on-rails. We have a several options about session storage such as cookie, active_record_store, etc.. I primarily use the cookie storage, but, there are some client which doesn't support cookie function. In that case, I have to make that client to use the "active_record_store". My rails version is 2.3.5. I found out that even though I use the active_record_store, the cookie is still available. In my situation, both session storage might be available. So, I want to make the framework to primarily use the cookie, when the cookie is available. On the other hand, the client doesn't support the cookie, secondly to use the active_record_store. I think this function requires some override to the framework, but I don't know how to do it. Do you have any idea for that? Thank you very much in advance.

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  • Metacity malfunction preventing custom Gnome session from launching?

    - by QuietThud
    When I try to run Metacity in Ubuntu2D(12.04), I get the following message: alisa@ubuntu:~$ metacity Window manager warning: Screen 0 on display ":2.0" already has a window manager; try using the --replace option to replace the current window manager. I get the same message when running Compiz from the command line in 3D (it opens fine through the GUI (same thing for AWN)). I understand that these should be the default managers for the respective sessions. I'm trying to create a custom Gnome session using the following instructions: unity launcher-free session. Here is what I've put into my .session file: [GNOME Session] Name=Custom Unity2D Session RequiredComponents=gnome-settings-daemon; RequiredProviders=windowmanager;panel; DefaultProvider-windowmanager=metacity DefaultProvider-panel=unity-2d-panel FallbackSession=ubuntu-2d DesktopName=GNOME Since I'm having problems identifying my default, and the code refers to Metacity, I figured this may be relevant to my inability to load the custom session (it shows up on my login screen, but won't launch). I tried specifying Metacity as my default manager by adding exec metacity to the .xinitrc file, and I tried running metacity --replace, but neither worked. How do I determine my current default window manager, what should the default be, and how do I re-assign it? Also, please let me know if you think there may be other issues affecting my custom session. I am new to Linux, so list anything you think might be helpful. Thank you!

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  • How does this Singleton-like web class persists session data, even though session is not updated in

    - by Micah Burnett
    Ok, I've got this singleton-like web class which uses session to maintain state. I initially thought I was going to have to manipulate the session variables on each "set" so that the new values were updated in the session. However I tried using it as-is, and somehow, it remembers state. For example, if run this code on one page: UserContext.Current.User.FirstName = "Micah"; And run this code in a different browser tab, FirstName is displayed correctly: Response.Write(UserContext.Current.User.FirstName); Can someone tell me (prove) how this data is getting persisted in the session? Here is the class: using System; using System.Collections.Generic; using System.Linq; using System.Web; public class UserContext { private UserContext() { } public static UserContext Current { get { if (System.Web.HttpContext.Current.Session["UserContext"] == null) { UserContext uc = new UserContext(); uc.User = new User(); System.Web.HttpContext.Current.Session["UserContext"] = uc; } return (UserContext)System.Web.HttpContext.Current.Session["UserContext"]; } } private string HospitalField; public string Hospital { get { return HospitalField; } set { HospitalField = value; ContractField = null; ModelType = null; } } private string ContractField; public string Contract { get { return ContractField; } set { ContractField = value; ModelType = string.Empty; } } private string ModelTypeField; public string ModelType { get { return ModelTypeField; } set { ModelTypeField = value; } } private User UserField; public User User { get { return UserField; } set { UserField = value; } } public void DoSomething() { } } public class User { public int UserId { get; set; } public string FirstName { get; set; } } I added this to a watch, and can see that the session variable is definitely being set somewhere: (UserContext)System.Web.HttpContext.Current.Session["UserContext"]; As soon as a setter is called the Session var is immediately updated: set { HospitalField = value; //<--- here ContractField = null; ModelType = null; }

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  • Java: Tracking a user login session - Session EJBs vs HTTPSession

    - by bguiz
    If I want to keep track of a conversational state with each client using my web application, which is the better alternative - a Session Bean or a HTTP Session - to use? Using HTTP Session: //request is a variable of the class javax.servlet.http.HttpServletRequest //UserState is a POJO HttpSession session = request.getSession(true); UserState state = (UserState)(session.getAttribute("UserState")); if (state == null) { //create default value .. } String uid = state.getUID(); //now do things with the user id Using Session EJB: In the implementation of ServletContextListener registered as a Web Application Listener in WEB-INF/web.xml: //UserState NOT a POJO this this time, it is //the interface of the UserStateBean Stateful Session EJB @EJB private UserState userStateBean; public void contextInitialized(ServletContextEvent sce) { ServletContext servletContext = sce.getServletContext(); servletContext.setAttribute("UserState", userStateBean); ... In a JSP: public void jspInit() { UserState state = (UserState)(getServletContext().getAttribute("UserState")); ... } Elsewhere in the body of the same JSP: String uid = state.getUID(); //now do things with the user id It seems to me that the they are almost the same, with the main difference being that the UserState instance is being transported in the HttpRequest.HttpSession in the former, and in a ServletContext in the case of the latter. Which of the two methods is more robust, and why?

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  • Different types of Session state management options available with ASP.NET

    - by Aamir Hasan
    ASP.NET provides In-Process and Out-of-Process state management.In-Process stores the session in memory on the web server.This requires the a "sticky-server" (or no load-balancing) so that the user is always reconnected to the same web server.Out-of-Process Session state management stores data in an external data source.The external data source may be either a SQL Server or a State Server service.Out-of-Process state management requires that all objects stored in session are serializable.Linkhttp://msdn.microsoft.com/en-us/library/ms178586%28VS.80%29.aspx

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  • Save chromium browser's session

    - by Anwar Shah
    How to manually save session in chromium-brower. I have a Notebook with damaged battery (only gives 5~6 minutes of backup, planning to buy a new one), and in our country "Load Shedding" (power outages) is quite common. So, I had to close my session before shutting down my laptop. When I re-open chromium, there is no tab with previous session. The question is: How can i manually save my session before closing the laptop?

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  • XFCE session with GNOME in background

    - by 100rabh
    Hi askUbuntu I recently installed XFCE on my Ubuntu 10.04 and it runs finely but with an issue. Everytime I login into my XFCE session I see the background image of GNOME session and after few seconds it disappears which gives me the impression that XFCE session is running over an already running GNOME session. If that is really the case then it might also be eating into my system's RAM which could be a bug. All helps and suggestions are welcome.

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  • Session Bean returning another Remote Session Bean reference [JBOSS]

    - by mrlinx
    Hi all, I have a Stateless Session Bean in my JBoss Server that contains a function returning an instance of another Session Bean (this one is stateful). My problem arises because this returned object doesn't seem to keep its persistence model (the EntityManager is null). What is the right way to return from a Session Bean another Session Bean, keeping its remote "connection"?

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  • Communication between state machines with hidden transitions

    - by slartibartfast
    The question emerged for me in embedded programming but I think it can be applied to quite a number of general networking situations e.g. when a communication partner fails. Assume we have an application logic (a program) running on a computer and a gadget connected to that computer via e.g. a serial interface like RS232. The gadget has a red/green/blue LED and a button which disables the LED. The LEDs color can be driven by software commands over the serial interface and the state (red/green/blue/off) is read back and causes a reaction in the application logic. Asynchronous behaviour of the application logic with regard to the LED color down to a certain delay (depending on the execution cycle of the application) is tolerated. What we essentially have is a resource (the LED) which can not be reserved and handled atomically by software because the (organic) user can at any time press the button to interfere/break the software attempt to switch the LED color. Stripping this example from its physical outfit I dare to say that we have two communicating state machines A (application logic) and G (gadget) where G executes state changes unbeknownst to A (and also the other way round, but this is not significant in our example) and only A can be modified at a reasonable price. A needs to see the reaction and state of G in one piece of information which may be (slightly) outdated but not inconsistent with respect to the short time window when this information was generated on the side of G. What I am looking for is a concise method to handle such a situation in embedded software (i.e. no layer/framework like CORBA etc. available). A programming technique which is able to map the complete behaviour of both participants on classical interfaces of a classical programming language (C in this case). To complicate matters (or rather, to generalize), a simple high frequency communication cycle of A to G and back (IOW: A is rapidly polling G) is out of focus because of technical restrictions (delay of serial com, A not always active, etc.). What I currently see as a general solution is: the application logic A as one thread of execution an adapter object (proxy) PG (presenting G inside the computer), together with the serial driver as another thread a communication object between the two (A and PG) which is transactionally safe to exchange The two execution contexts (threads) on the computer may be multi-core or just interrupt driven or tasks in an RTOS. The com object contains the following data: suspected state (written by A): effectively a member of the power set of states in G (in our case: red, green, blue, off, red_or_green, red_or_blue, red_or_off...etc.) command data (written by A): test_if_off, switch_to_red, switch_to_green, switch_to_blue operation status (written by PG): operation_pending, success, wrong_state, link_broken new state (written by PG): red, green, blue, off The idea of the com object is that A writes whichever (set of) state it thinks G is in, together with a command. (Example: suspected state="red_or_green", command: "switch_to_blue") Notice that the commands issued by A will not work if the user has switched off the LED and A needs to know this. PG will pick up such a com object and try to send the command to G, receive its answer (or a timeout) and set the operation status and new state accordingly. A will take back the oject once it is no longer at operation_pending and can react to the outcome. The com object could be separated of course (into two objects, one for each direction) but I think it is convenient in nearly all instances to have the command close to the result. I would like to have major flaws pointed out or hear an entirely different view on such a situation.

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  • Reuse another ASP.NET session (set Session ID)

    - by queen3
    My problem is that when I open web application from Outlook in a separate IE window, the ASP.NET session is lost. This is (as described in several places) because in-memory cookie is lost. So it goes like this: User works with ASP.NET web application in Outlook, and this stores some info in ASP.NET session User clicks Print to open new IE window with print-ready data The new window has different ASP.NET session ID and can't access old data. I think, maybe, if I pass ASP.NET session ID to new IE window, I can somehow "attach" to that session? Tell ASP.NET that this is the one that I need to be current?

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  • ASP.Net Session data lost between pages

    - by Ananth
    Hi, i came across a weird behavior today w/ my web application. When I navigate from a page to another, I lose one particular session variable data. I'm able to launch the app in firefox and able to see that the session data is not lost. I use Response.Redirect(page2, false) to redirect to another page. Below code was used to track session variables System.IO.StreamWriter sw = new System.IO.StreamWriter(@"c:\test.txt", true); for (int i = 0; i < Session.Count; i++) { sw.WriteLine(Session.Keys[i] + " " + Session.Contents[i]); } sw.Close(); Can anyone help me in this? Any help is appreciated. ~/Ananth

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  • Session Mania: Content Catalog & Suggest-a-Session

    - by Justin Kestelyn
    As ably reported in the Oracle Technology Network blog, the Oracle Develop Conference's content catalog is now public (as are the catalogs for JavaOne and Oracle OpenWorld), meaning you can now explore technical sessions scheduled for the conf to your heart's content."But something's missing", you may tell yourself. "Where is my favorite subject, the one I happen to also be an expert on?" Well, there's good news for you, too: The Suggest-A-Session project has returned. It works thus: Submit a session idea via Oracle Mix and ask your colleagues, Oracle Mix community, friends and anyone else you know to vote for your session. (You must be an Oracle Mix member to vote.) Voting is open through June 20. For the most part, the top voted sessions will be selected for the Oracle Develop Conf (or Oracle OpenWorld) official agenda. See the FAQ for fine print.Apparently some people have already jumped into this loophole, including Oracle ACE Director Marco Gralike, who has "gone video" on us: Why wait? Suggest-a-session!

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  • Sending state diffs (deltas) and unreliable connections

    - by spaceOwl
    We're building a realtime multiplayer game, in which each player is responsible for reporting its state on every iteration of the game loop. The state updates are broadcasted using unreliable UDP. To minimize state data sending, we've come up with a system that will send only deltas (whatever state data that was changed). This method however is flawed, since a lost packet will mean that other players will not receive the delta, making the game behave in an unexpected way. For example: Assume that state is comprised of: { positionX, positionY, health } Frame 1 - positionX changed --> send a packet with positionX only. Frame 2 - health changed // lost ! Frame 3 - positionY changed --> send a packet with positionY only. // Other players don't know about health change. How can one overcome this issue then? sending the entire data is not always feasible.

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  • Constructs for wrapping a hardware state machine

    - by Henry Gomersall
    I am using a piece of hardware with a well defined C API. The hardware is stateful, with the relevant API calls needing to be in the correct order for the hardware to work properly. The API calls themselves will always return, passing back a flag that advises whether the call was successful, or if not, why not. The hardware will not be left in some ill defined state. In effect, the API calls advise indirectly of the current state of the hardware if the state is not correct to perform a given operation. It seems to be a pretty common hardware API style. My question is this: Is there a well established design pattern for wrapping such a hardware state machine in a high level language, such that consistency is maintained? My development is in Python. I ideally wish the hardware state machine to be abstracted to a much simpler state machine and wrapped in an object that represents the hardware. I'm not sure what should happen if an attempt is made to create multiple objects representing the same piece of hardware. I apologies for the slight vagueness, I'm not very knowledgeable in this area and so am fishing for assistance of the description as well!

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