Deploy multiple instances of the same stateless session EJB

I have a stateless session bean.
The methods on the bean operate against DB tables.
Q: Can I deploy multiple instances of the same stateless session bean, but specify a different JNDI/datasource name in the deployment descriptor?
The method calls are all enclosed within a single invocation, just that I need to hit different databases (all with the same schema), and Id like to be able to lookup the EJB via a different JNDI name, and have the exact same functionality, just against different deployed datasources.
Does the spec allow/support this?
If not, any suggestions as to how to achieve this sort of functionality?
Im using JBoss 3.2.1 on Solaris, so Im not sure whether or not this is a JBoss "issue" or a limitation of the EJB Spec (or me being just plain wrong and trying to do something the "wrong way")
Nick

I have a stateless session bean.
The methods on the bean operate against DB tables.
Q: Can I deploy multiple instances of the same
stateless session bean, but specify a different
JNDI/datasource name in the deployment descriptor?
The method calls are all enclosed within a single
invocation, just that I need to hit different
databases (all with the same schema), and Id like to
be able to lookup the EJB via a different JNDI name,
and have the exact same functionality, just against
different deployed datasources.
Does the spec allow/support this?
If not, any suggestions as to how to achieve this sort
of functionality?
Im using JBoss 3.2.1 on Solaris, so Im not sure
whether or not this is a JBoss "issue" or a limitation
of the EJB Spec (or me being just plain wrong and
trying to do something the "wrong way")
NickI haven't done it but judging from the deployment descriptors yes.
For example if I have two bounded datasources java:/Database1 and java:/Database2
Lets say I have a session bean called MySession, then in your ejb-jar.xml you would have (notice that the desc, display, and ejb-name are the only differences)
<session>
<description>MySessionAlpha</description>
<display-name>MySessionAlpha</display-name>
<ejb-name>MySessionAlpha</ejb-name>
<home>com.mycorp.MySessionRemoteHome</home>
<remote>com.mycorp.MySessionRemote</remote>
<local-home>com.mycorp.MySessionLocalHome</local-home>
<local>com.mycorp.MySessionLocal</local>
<ejb-class>com.mycorp.MySessionFacadeBean</ejb-class>
<session-type>Stateless</session-type>
<transaction-type>Container</transaction-type>
<resource-ref>
<res-ref-name>jdbc/DataSource</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
</session>
<session>
<description>MySessionBeta</description>
<display-name>MySessionBeta</display-name>
<ejb-name>MySessionBeta</ejb-name>
<home>com.mycorp.MySessionRemoteHome</home>
<remote>com.mycorp.MySessionRemote</remote>
<local-home>com.mycorp.MySessionLocalHome</local-home>
<local>com.mycorp.MySessionLocal</local>
<ejb-class>com.mycorp.MySessionFacadeBean</ejb-class>
<session-type>Stateless</session-type>
<transaction-type>Container</transaction-type>
<resource-ref>
<res-ref-name>jdbc/DataSource</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
</session>
But now in the jboss.xml, we will have the following elements. What you may notice is that are bound to different remote and local jndi names. But the resource bindings are very different. The res-ref-name stays the same, but the jndi-name are different. I think this will work for you.
<session>
<ejb-name>MySessionAlpha</ejb-name> <jndi-name>ejb/com/mycorp/MySessionAlphaRemoteHome</jndi-name> <local-jndi-name>ejb/com/mycorp/MySessionAlphaLocalHome</local-jndi-name>
<resource-ref>
<res-ref-name>jdbc/datasource</res-ref-name>
<jndi-name>java:/Database1</jndi-name>
</resource-ref>
</session>
<session>
<ejb-name>MySessionBeta</ejb-name> <jndi-name>ejb/com/mycorp/MySessionBetaRemoteHome</jndi-name> <local-jndi-name>ejb/com/mycorp/MySessionBetaLocalHome</local-jndi-name>
<resource-ref>
<res-ref-name>jdbc/datasource</res-ref-name>
<jndi-name>java:/Database2</jndi-name>
</resource-ref>
</session>

Similar Messages

  • Multiple instances of the same bean class in session?

    I�m trying to think of a way to have multiple instances of the same bean class in session scope using JSF. For example, let�s say that I have two <h:dataTable>s on the same page. They both use the backing bean called genericBean. Now, the content for genericBean will be different for each <h:dataTable>. In fact, the data source that backs genericBean is not known until runtime. It could be a database, web service, etc.
    What I would like is for when JSF needs access genericBean instead of looking for the value with key �genericBean� in the session map it looks for �genericBean_[some runtime ID]�. I could specify this id in EL on a custom component, as a request parameter or whatever.
    I think that I need the bean to be in session scope because the tables are complex and I want them to be editable.
    I have some ideas about how I can do this but I was wondering if someone has already solved this problem or if there is a standard way to do this using tools like Shale, etc.
    Thanks,
    Randy

    Well, I came up with an interesting solution to this so I thought that I would post it here.
    I have a page that looks like this.
    <html>
    <head>
    <title>My Page</title>
    </head>
    <body>
    <f:view>
    <f:subview id="component1">
    <jsp:include page="component.jsp">
    <jsp:param name="id" value="a" />
    </jsp:include>
    </f:subview>
    <hr>
    <f:subview id="component2">
    <jsp:include page="component.jsp">
    <jsp:param name="id" value="b" />
    </jsp:include>
    </f:subview>
    </f:view>
    </body>
    </html>
    And component.jsp looke like this.
    <f:verbatim>
    <p>
    <h1>Component
    </f:verbatim>
    <h:outputText value=" #{param.id}" />
    <f:verbatim>
    </h1>
    </p>
    </f:verbatim>
    <h:form>
    <h:outputText value="#{component.id}" />
    <h:outputText value="#{component.value}" />
    <h:commandButton value="increment" action="#{component.increment}" />
    <h:commandButton value="decrement" action="#{component.decrement}" />
    <f:verbatim>
    <input type="hidden" name="id"
    value="</f:verbatim><h:outputText value="#{param.id}"/><f:verbatim>" />
    </f:verbatim>
    </h:form>
    The idea is that I want component.jsp to be initialized differently based on the id param. The component managed bean is configured to be in session scope but I want the component instance for id a and id b to be different instances in session scope. Therefore, I added a custom variable resolver to handle this.
    public Object resolveVariable(FacesContext context, String name) {
    // This id will be different for the different subviews.
    HttpServletRequest request = (HttpServletRequest) context.getExternalContext() .getRequest();
    String id = request.getParameter("id");
    // If there is an id in the request then check if this is a bean that can have multiple
    // instances in session scope.
    if ((id != null) && (id.length() > 0)) {
    ExternalContext ec = context.getExternalContext();
    // Build the new name for the key of this bean
    String newName = name + "_" + id;
    Object value = null;
    // See if the bean instance already esists.
    if ((null == (value = ec.getRequestMap().get(newName))) &&
    (null == (value = ec.getSessionMap().get(newName))) &&
    (null == (value = ec.getApplicationMap().get(newName)))) {
         // We could not find the bean instance in scope so create the bean
         // using the standard variable resolver.
    value = original.resolveVariable(context, name);
    // Now check if the bean implements that page component interface. If it is
    // a page component then we want to rename the key to access this bean so
    // that the instance is only used when the id is provided in the request.
    // For example, if there are two components (a and b) we will have in session scope
    // component_a and component_b. The will each point to a unique instance of the
    // Component bean class.
    if (value instanceof PageComponent) {
    // Try to get the value again
    if (null != (value = ec.getRequestMap().get(name))) {
         // Initialize the bean using the id
    ((PageComponent) value).initInstance(id);
    ec.getRequestMap().remove(name);
    ec.getRequestMap().put(newName, value);
    } else if (null != (value = ec.getSessionMap().get(name))) {
    ((PageComponent) value).initInstance(id);
    ec.getSessionMap().remove(name);
    ec.getSessionMap().put(newName, value);
    } else if (null != (value = ec.getApplicationMap().get(name))) {
    ((PageComponent) value).initInstance(id);
    ec.getApplicationMap().remove(name);
    ec.getApplicationMap().put(newName, value);
    return value;
    return original.resolveVariable(context, name);
    }

  • Multiple instances of the same APEX application under SSO

    Currently we have several applications that are authenticated through Oracle SSO. The apps are authenticating correctly, but I can't be in multiple instances of the same application without having to re-validate through SSO when I move between instances.
    Scenario: I'm successfully signed into my "parent" application, app_id 1 through SSO. I click a custom link that opens the "child" application (app_id 2) to view widget "A". When the page is launched I see the usual "Redirecting to the Login Server for authentication" message (verifying that I'm signed in through SSO) and then it succeeds and takes me into app 2, displaying widget A. I click the next link to launch another instance of app 2 with a different APEX session id for viewing widget "B". This also passes through SSO and redirects me into app 2, displaying widget B as expected. But now if I go back to navigate anywhere on widget A in my first instance, it has to go back through the "Redirecting to Login Server." This now means the widget A window is valid, but the widget B window will have to redirect next time I use it (back & forth & so on...)
    So my question I suppose is: Is it possible/good practice to allow a single user to open multiple separate instances of the same APEX application using different APEX session_ids viewing different data under Oracle Enterprise SSO?
    Guesstimation: It seems like there must be a switch somewhere in SSO that says "allow multiple application instances yes/no"...but my problem may be APEX itself, or how SSO is tied into APEX... Sorry for the super-generic example, I'm not exactly sure where I should be looking to resolve this, and the closest similar problem I found on the forums was here: login to application twice in two seperate IE  windows clears other login

    reset your dock preferences. delete the file homedirectory/library/preferences/com.apple.dock.plist and log out/in. your dock, spaces and exposé will be reset to the defaults. see if the problem goes away.

  • Is there any version of Indesign that allows to open multiple instance at the same time

    I am using Indesign CS3 to generate the bulk reports automatically(programmatically) using Adobe indesign library . One of the key limitation to this tool is it allows to open only one instance at a time unlike word where multiple instances can be opened at the same time. Is there any adobe indesign too version desktop/server which allows to open multiple instances at the same time. Any help on is appreciated. Thanks.

    @PeterG
    You said "You might want to examine the End User Licensing Agreement (EULA) for  any prohibition against using these two instances at the same time with  the same license; the license does permit two installs for the same user  that are not used simultaneously." I thought that meant you had read the EULA. It's pretty unambiguous on that point.
    For everyone's edification about multiple installations and server use with a standard license here's the relevant text:
    2. Software License.
    If you obtained the Software and any required serial number(s) from Adobe or one of its authorized
    licensees and as long as you comply with the terms of this agreement, Adobe grants you a non-exclusive
    license to install and use the Software in a manner consistent with its design and Documentation and as
    further set forth below. See Section 16 for specific provisions related to the use of certain products and
    components, for example font software, Acrobat, After Effects, Adobe Presenter, Contribute, Adobe
    Device Central, Flash Player, Flash Builder, and Adobe Runtimes.
    2.1 Limited Use. The Software, or portions of the Software, may allow installation and use without a serial
    number. If so, you may install but not use such non-serialized Software on any number of Computers as
    part of an organizational deployment plan. Further, you may install and use such non-serialized Software
    on any number of Computers for demonstration, evaluation and training purposes only and only if any
    Output Files or other materials produced through such use are used only for internal, non-commercial and
    non-production purposes. You may not use such non-serialized Software after any applicable time-out
    period has ended, unless you input a valid serial number under Section 2.2. ACCESS TO AND USE OF
    ANY OUTPUT FILES CREATED WITH SUCH NON-SERIALIZED SOFTWARE IS ENTIRELY AT
    YOUR OWN RISK.
    2.2 General Use. You may install and use one copy of the Software only on the Permitted Number of your
    compatible Computers into which you enter a valid serial number.
    2.3 Distribution from Server. You may copy an image of the Software onto Computer file server(s) within
    your Internal Network for the purpose of downloading and installing the Software onto Computers within
    the same Internal Network for use as permitted by Section 2.1 and 2.2.
    2.4 Server Use. You may install the Software on Computer file server(s) within your Internal Network only
    for use of the Software initiated by an individual from a Computer within the same Internal Network only
    as permitted by Section 2.2. The total number of users (not the concurrent number of users) able to use the
    Software on such Computer file server(s) may not exceed the Permitted Number.
    By way of example, the foregoing does not permit you to install or access (either directly or through
    commands, data or instructions) the Software: (a) from or to a Computer not part of your Internal Network,
    (b) for enabling Web hosted workgroups or services available to the public, (c) by any individual or entity
    to use, download, copy or otherwise benefit from the functionality of the Software unless licensed to do so
    by Adobe, (d) as a component of a system, workflow or service accessible by more than the Permitted
    Number of users, or (e) for operations not initiated by an individual user (e.g., automated server
    processing).
    2.5 Portable or Home Computer Use. Subject to the important restrictions set forth in Section 2.6, the
    primary user of the Computer on which the Software is installed under Section 2.2 (“Primary User”) may
    install a second copy of the Software for his or her exclusive use on either a portable Computer or a
    Computer located at his or her home, provided that the Software on the portable or home Computer is not
    used at the same time as the Software on the primary Computer.
    2.6 Restrictions on Secondary Use by Volume Licensees. If the Software was obtained under an Adobe
    volume license program (currently known as Adobe Open Options) by any licensee other than an
    educational volume licensee, the second copy of the Software made under Section 2.5 must be used solely
    for the benefit and business of that volume licensee. For more information about secondary use by volume
    licensees, please visit our Web Site at http://www.adobe.com/go/open_options.
    There is also language stating that if you have a dual boot or other system capable of running more than one OS you will need a separate license for each platform if you want to run the software on more than one.

  • How can I open multiple instances of the same version of FF?

    I understand that if I have multiple profiles, I can run different versions of FF side-by-side (like 3.6 and 4).
    However, what I'm interested in is how I can launch multiple instances of the same version of FF (4, for instance) using the same profile. In other words, I want to be able to double-click the desktop icon for FF, and open a new instance, and keep doing that as many times as I want. I don't want to have a different icon and profile for each instance (too much overhead to keep a dozen+ profiles in sync).
    I can always launch one FF window instance, and then keep clicking ctrl+N to launch new instances from inside it, which they all share the same profile (as I want). So, basically, I want to be able to do that from my desktop icon, rather than by having to do it with the keyboard ctrl+N sequence.

    But I don't understand why whatever Firefox does when you click ctrl+N can't also be done (with some sort of command-line switch) from a desktop icon?
    In other words, I clearly can create many FF instances (even if they are the same FF.exe process) by doing ctrl+n a bunch of times. Why then can't this behavior be done from a desktop icon with some parameters?
    As far as I know, FF is the only browser that doesn't directly allow multiple browser instances from desktop icons. IE, Chrome, Safari, Opera, etc... all let me launch a new instance (even if they are all single process and the instances are shared within the process).

  • Cant open external links and multiple instances of the same profile.

    I have multiple firefox profiles.
    I constantly have two profiles running at the same time.
    I use microsoft outlook and see an external link, I click it wishing firefox to open it in the default or new browser. It does not and says "FIrefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system."
    Firefox is running fine.
    How can I open external links with a profile based setup?
    Also, how can I open multiple instances of the same profile? I find that if I click and drag a tab to another monitor, it opens a new "instance" or browser window.

    You say
    ''I have multiple firefox profiles. <br />
    I constantly have two profiles running at the same time. ''
    So you will have discovered ''-no-remote'' Note NOT to use that on the default browser; profile, only on secondary profiles.
    * http://kb.mozillazine.org/Profile_in_use#Common_causes
    You will NOT be able to open multiple instances of the same profile, clone the profile if necessary.
    If you are trying to run multiple Webmail accounts in one profile then you may well find the webmail is identifying and setting the user account that is opened. Use a Private Browsing window to get round that and open a second account.
    * [[Private Browsing - Browse the web without saving information about the sites you visit]]

  • Best practice for multiple instances of the same BEX query

    Hi there,
    I'm wondering what's the best way to use multiple instances of the same BEX query. Let me explain what I mean:
    I have a dashboard with different queries feeding different period of time such as: week to date, month to date and so on. One query for each since it is based on a user exit.
    For each query I want to show different data in different sections of my dashboard. Per example: sales per directors or sales per customer group, sales per day, sales per week and the like.I tried to connect a simple bar chart via a direct connection but with no success due to the multiple lines generated by the addition of the sales director, customer group, week number and so on.
    My question is about the way to connect the different queries efficiently in order to show the different data while avoiding multiple useless lines.
    The image above shows the query browser where, per example, for a Month to date query there will be mutiple line for each week as well as one line for each director. If, for two different components, I want to show data per week and data per director or other representation what is the best practice:
    Add another instance of the same query and only put the week information and another one will only the director info?
    Should I bind those to the excel file and use formulas to make final calculations?
    Will there be a performance issues for adding different instances of the same query
    I have 6 different queries (read 6 user exit that filters time via user exit).
    Depending on the best practices there might be 4 instances for each for a total of 24 instances in the query browser.
    I hope my question is clear enough, if not please do not hesitate I'll clarify as much as possible.
    Regards,
    Steve

    Hi Steve,
    Might be trying for solution for a long time, If i understood your question clear let me clarify you few points.
    You are trying to access the bex query which is designed with the exit's in the background based on the logic and trying to call the entire dimensions and key-figures in a single connection. Then you are trying to map those data in the charts.
    Steve, try to make more connections based upon the logic and split them. use the same query but split them by sales per customer group, sales per day, sales per week by making three different connections and try. You can merge the prompts from all connections.
    Hope this Helps!!!
    Sorry if i misunderstood your question.
    --SumanT

  • Stop opening multiple instances of the same application

    I am used to having graphic files on my desktop, when editing one I would simply right-click and pick "open with" > Photoshop (which is always open in its own desktop in my computer). Now out of the blue, if I do that, it loads another instance of Photoshop, which is certainly what I don't want. I can have 2, 3, 4 Photoshops running at the same time and editing the same image!
    Any idea how to solve this? I searched but all I could find is people wanting the opposite i.e. opening multiple instances of the same app.

    Your best bet to prevent this is to detach or unmount this drive; however, you can also try resetting your Mac's launch services, to have it re-scan only the Applications folders on your boot drive for programs to associate with documents and services you are using. Running the following command in the OS X Terminal will kill the current launch services database (its long, but copy and paste the entire line):
    /System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill
    Following this, run the following command to seed the database with the apps you currently have installed:
    /System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -seed
    Note that these changes will only apply when opening documents that have not been specifically assigned to a program. If you find a specific document continues to open the program on the external drive, then you can get info on it and change the associated program in the "Open With" section of the info window. After doing this, you might need to re-run these commands above, as opening the program will register it with OS X's launch services and have it now be available for automatically handling other documents.

  • Opening multiple instances of the same vi

    Hi,
    I am having trouble opening multiple instances of the same vi.
    This vi that I am trying to create can be used like a message display window to display numbers, strings etc (just like labVIEW's display message control except that this vi will update the displayed controls every scan). So for example, I will like to have a subvi, lets call it popup.vi, where I wire in three inputs from my main vi (2 strings and 1 number). Now in my main.vi I have 2 numeric controls Num1 and Num2 with their KeyFocus property nodes.
    The intention is that when I select Num1 or Num2 numeric control with my mouse the KeyFocus boolean becomes true and the popup.vi logic kicks in. Meaning that the popup.vi runs and opens its front pane
    l displaying the two strings and one numeric value from the main.vi.
    The problem arises when I want to open and run multiple instances of the popup.vi.
    So when I click on Num1 with my mouse I want the popup.vi to open its front panel with a set of strings and number displayed. At the same time I would want to click on Num2 control and open another instance of the popup.vi with another set of strings and numeric value.
    Also, I saved the popup.vi as popup.vit but for some reason vi server will not open the popup.vit. I get a message that popup.vit is already in memory - cannot load.
    I have attached a sample of the main.vi and popup.vi program.
    Please let me know if you need further clarifications.
    I appreciate your help in this matter.
    Thanks
    Nish
    Attachments:
    popupVI.zip ‏37 KB

    You have to clone the VI. You say you have tried to use the .vit way of cloning...but in the example there is no use of VIT and the VI is called statically. If you want to open multiple instances of the same VI and the VI has a user interface (or needs to be a unique instance of the VI every time even though it's called the same place in the diagram, not the case here though) you need to do it dynamically, i.e. with an invoke node.
    There is actually a problem doing just that, it causes a memory leak...but that won't be a problem unless the VI is called frequently / the software will be running over very long periods of time. You can see an example of it here (attached to my reply to the question):
    http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&
    RPAGEID=135&HOID=506500000008000000A07D0000&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0&USEARCHCONTEXT_QUESTION_0=VI+cloning&USEARCHCONTEXT_QUESTION_S=0
    About the memory leak problem:
    http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=506500000008000000B7A40000&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0&USEARCHCONTEXT_QUESTION_0=VI+cloning&USEARCHCONTEXT_QUESTION_S=0
    MTO

  • Problem:Multiple instances of the same applet on a webpage...

    I have an applet which connects to a server to read an XML-file.
    I use Doucument to parse the XML-file like this:
    String xmlurl="http://www.somesite.com/somexmlpage.php";
    Document d =DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(xmlurl);
    (...read the XML-file...)
    This works fine.
    However, I need multiple instances of the same applet running at the same time on the same webpage.
    Now, with multiple applets running at the same time the parsing no loger works. If one applet is doing some parsing and a taskswitch takes place to let another applet run, the applet which is interrupted is not able to continue the parsing as it looses its "incoming data" when another applet reads from the server.
    How can different applets affect each other like this?
    And how can I fix the problem?
    Thanks in advance for any help!!

    However, I need multiple instances of the same applet running at the same time on the same webpage.
    Why? But okay.Because the the different applets show information about different items.
    Now, with multiple applets running at the same time the parsing no loger works. If one applet is doing some parsing and a
    taskswitch takes place to let another applet run, the applet which is interrupted is not able to continue the
    parsing as it looses its "incoming data" when another applet reads from the server.
    How did you determine that's what's happening?By printing out debuginformation.
    Each applet prints out a message (System.out.println) when it creates an instance of Document (ie. connects to the server) and the applet also prints out XML-information as the XML-file is processed.
    But, actually, I was a bit quick in my first post; The applet doesen't neccesarily loose its "incoming data", but the parser looses the data it is parsing. I can download the data from the server first, and then start parsing it. If a taskswitch happens while one applet is parsing, it looses its data, even if the data is allready downloaded.
    I see this since I see another applet making a printout, and when first applet starts again, the parser has lost track of its data.
    It works fine if only one applet is running. And everything is fine until the next applets starts; I can see this from the printout.
    Again, the appet prints out data as it parses the document. I see the next applet starting to work, and when the first one continues parsing again the printout shows that data is no longer there. It happens everytime the runtime switches to another applet, and it never happens if just one applet is running.
    Googeling a little tells me that DocumentBuilder.parse() isn't thread-safe, but this shouldn't have anything to do with it, should it?
    Each applet is a separate process, and not different threads in the same process, aren't they? (Not sure how the runtime treats multiple applets...)And secondly, the applets create their own instance of Document anyways.

  • Multiple instances of the same VI running in parallel

    Hi,
    I have a timestamping subVI that looks at a counter channel and applies timestamps. I want to create multiple instances of this subVI (8 to be exact) and have them all run in parallel (looking at 8 different channels). Someone gave me the following advice:
    >>
    Also, in case you want to call multiple instances of the same SubVI, and you want these multiple instances to execute in parallel, you will have to set the SubVI to execute in reentrant mode. Do this by opening the SubVI and going to "Edit >> VI Properties >> Execution" and enable "Reentrant execution".
    <<
    I've tried this but only my second instance (I started simple with only 2 instances) seems to monitor its channel and pass data along to the queue. I've included my code below, I have two signal simulators which simulate singles coming in on channels 2 and 3. I'm using a PCQI 6602 counter/timer card.
    Any help would be greatly appreciated, thanks in advance,
    Chris
    Attachments:
    LabView App (June 28, 2005).zip ‏158 KB

    good news! Your reentrant VI is working and all three instances are running (as execution highlighting clearly shows). The problem is going to be an error that is occuring but you don't see because you are ignoring the error clusters internally in the timer. It looks like at one point it was set to quit if an error occurred. That still needs to be there.
    Always hookup error clusters...
    Mike...
    Certified Professional Instructor
    Certified LabVIEW Architect
    LabVIEW Champion
    "... after all, He's not a tame lion..."
    Be thinking ahead and mark your dance card for NI Week 2015 now: TS 6139 - Object Oriented First Steps

  • Disallow running multiple instances of the same web start application..

    on the client? I have an application that is launched on the client by clicking on the link to the JNLP file. The problem is that I don't want the application to launch twice if the user clicks the link twice. Is there a way to keep web start from running multiple instances of the same app?
    I don't want to just disable the button after it is clicked because then the user won't be able to get back in if they need to.
    Any help out there?
    Thanks,
    Melanie

    The way I do this is to try connect to an obscure port number on the localhost at startup.
    if this connection succeeds I assume the app is already running. otherwise the program continues and registers as a server at that port number.
    I actually take this a little bit further by registering a web server at this port (I use the Brazil server), That way if the program finds an instance of itself running it can send a message to the web server and ask the program to do something (like start another window if,for instance you wanted to allow this but only within the same VM).

  • Error 1127 occurred when open multiple instances of the same LabVIEW top level VI?

    I try to open multiple instances of the same LabVIEW top level VI, After search some messages in the forum,I know it should use vi template, But error 1127 still occurred when i used template(In my program, Click menu file->new). The information about error 1127 is  "Cannot instantiate template VI because it is already in memory".
    Here is my code. can any one help me? Thanks.
    Attachments:
    test.zip ‏13 KB

    Hi,
    You are trying to obtain a path from the VI location but the VI has no location because its an instance of the VIT and therefore the path is <not a path>.
    Regards
    Ray Farmer
    Regards
    Ray Farmer

  • Contribute multiple instances of the same connection appear on login/start screen

    I am administering a series of sub-websites under one primary umbrella.
    - The Primary Umbrella site does not run under the Contribute Publishing Server
    - The secondary (child) sites are managed by the Contribute Publishing Server
    - We recently added a user to several of these subsites
    - After we added the user, we've had a problem with other user profiles.
    - Multiple instances of the same connection will appear upon login on the start screen ( about:startscreen ). However the user seems to only be able to credential to one of them, not both.
    I have gone into the user profile directory within Windows directory structure and removed both site dirs. However when restarting and reconnecting, both appear again.
    Anyone else have this issue and what is the remedy and fix?

    I tried to add a screenshot, however it would not let me upload.
    I get: An error occurred while trying to submit your post. Please try again.

  • Multiple instances of the same entity bean?

    I am designing a J2EE application that is made up of a number of separate components that each have a well-defined responsibility. Each component is made up of one or more J2EE components (web clients and EJBs). I want to design the application such that it is easy in the future to deploy each component (or a group of components) on different servers. In order to do this I need to make sure that the interfaces between each component are exposed as remote interfaces (but I will use local interfaces inside each component). However, there are a number of entity beans that need to be accessed by more than one component. I am wondering how best to expose these entity beans. I believe there are a number of options:
    1. Expose remote interfaces on each of the shared entity beans. The disadvantage of this approach is that it is inefficient and that I will not be able to take advantage of container managed relationships. (I am intending to use container managed persistence.)
    2. Create a facade object (stateful session bean) for each of the entity beans which exposes a remote interface and in turn accesses the shared entity beans locally. The disadvantage of this approach is that I have to create some extra EJBs and that I cannot directly make use of container managed relationships etc from the client component.
    3. I don't know if this is an option but I am wondering whether I can deploy a copy of each shared entity bean with each application component. The advantage of this approach is that the component would access the entity locally and could make use of container managed relationships. However, I don't know what the issues are with having more than one instance (per primary-key) of an entity in the same application. I don't know whether this would cause errors of whether they would get out of sync (because different instances with the same primary key would be updated by different clients). Initially each component would be deployed in the same server but later they would be deployed in different servers. In both cases with this option each component (JAR) would have copies of the shared entity bean classes.
    Any suggestions as to the best approach and whether the last option is feasible would be much appreciated.
    Thanks.

    I think 2 beats 1. The main reason being to minimise the number of network calls. You're basically asking, are fascades a good idea? and the answer is yes.
    You can obviously do 3 in different app servers. However you'll need to configure your app servers so they can handle the fact that they're not the only ones updating the database. This is to handle concurrency as you mentioned. How you do this will depend on your app server and will affect performance, but shouldn't be a problem.
    I think you should definately decide up front what's going in different app servers, I dunno if 3 would work in the same app server.
    Why do you would want to use multiple app servers?
    Why not have everything in the same app?
    Is is just the 1 database?
    You can use clustering for scalability.

Maybe you are looking for

  • Dymo labels javascript (API) issue

    Hi all. APEX 4.2 11gR2 XE database. I'm trying to print labels directly from APEX via a JS library from DYMO (DYMO label framework for javascript). I would like to fetch the XML for the label layout dynamically from the database instead of fixed assi

  • Extrpoc role in a pl/sql in oracle form

    what role extproc play while calling an external procedure in oracle form

  • How to display image returned from servlet?

    Currently: I am getting an image from a database and displaying it using the below code. Desired: I want to display HTML also, not just the image. response.setContentType("image/jpg"); ServletOutputStream out = response.getOutputStream();        java

  • Help with parsing logs

    Does anybody know of any tools or reference materials i can used to research how to parse log files

  • Uninstall Bridge CS3

    I have both Bridge CS3 and CS4 installed on my system. Neither of them show up in my list of programs from the Control Panel Programs and Features. I want to uninstall CS3. How do I do that?