Service Locator pattern question.

Hi,
We have this kind of service locator which provides the caller a reference to a remote interface instead of to the home interface of the session bean. We're working with weblogic 6.1. My question, is it ok to store a reference to a remote interface in the service locator or is it better to store a reference to the home interface or .... is it better to not store them but every time create one when a client wants one. What is the best way and the pros and cons.
Cheers!

Hi,
typically it is more common to just cache Homes and Factories in the ServiceLocator pattern.
We have a detailed example of the Service Locator pattern applied in an application at http://java.sun.com/blueprints/patterns/ServiceLocator.html
We cache the EJB Homes and other Factories.
http://java.sun.com/blueprints/code/jps131/src/com/sun/j2ee/blueprints/servicelocator/web/ServiceLocator.java.html
This allows the Service Locator to be used as a utility class. We have a Service Locator used by the web tier, and also one used by the EJB tier to lookup other EJBs and resources.
hope that helps,
Sean

Similar Messages

  • Service Locator Pattern

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    If it has to be synchronized, doesnt it introduce performance bottle neck by letting only 1 thread access the method at any time?
    Please see code snippet below...
    Thanks,
    Krish
    public static synchronized EJBHome getHome(Class homeClass) throws NamingExeption {
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    if(home == null) {
    ctx = getInitialContext();
    home = (EJBHome) PortableRemoteObject.narrow(ctx.lookup(homeClass.getName()),homeClass);
    this.homes.put(homeClass,home);
    return home;
    }

    Hi,
    Take a look at the below thread on server side which discusses this issue in details.
    http://www.theserverside.com/discussions/thread.tss?thread_id=14992
    Anil

  • Using service Locator pattern to dynamically access remote EJBs

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    There are a lot of tools out there.
    Here's what I've used:
    On Windows/Linux, OptimizeIt and Jprobe are pretty common.
    If you're using jrockit, try JRA
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    On HP-UX, I like HP's JMeter:
    http://www.hpjmeter.com
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    Krish wrote:
    Is there a Profiling tool that I could use to identify where most of the time is
    being spent?
    Thx,
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    Krish wrote:
    We currently have an application with numerious EJBs. Obviously, thisin turn involves
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    the EJBs run within the same JVM, however not as part of a singe EARapplication
    (the EJBs are deployed as standalone application modules). We do nothave any
    Service Locator (J2EE pattern) implemented. My question is, given thisscenario,
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    cache JNDI look-ups? If so, Will this come into play if we deploy theapp as an
    EAR?
    Thanks,
    Krish

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    Thanks for ur help.

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    /Ashwani

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    Hello,
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    Thanks in advance

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    Hi Yves,
    But i would like to understand at which side should
    that service locator object reside??!!??
    If it is at client side, each client needs his own
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    Conclusion :
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    You may also want to visit the J2EE Pattern interest list
    and see these relevant discussions :
    Topic: Service Locator and passivation
    http://archives.java.sun.com/cgi-bin/wa?A2=ind0106&L=j2eepatterns-interest&F=&S=&P=1026
    Topic: Caching EJBHome interfaces
    http://archives.java.sun.com/cgi-bin/wa?A2=ind0106&L=j2eepatterns-interest&F=&S=&P=9226
    Topic: Using Service Locator for Data Source caching
    http://archives.java.sun.com/cgi-bin/wa?A1=ind0106&L=j2eepatterns-interest#31
    hope this helps,
    thanks,
    -deepak

  • Service Locator and session facade pattern

    What are differences between Service Locator and session facade pattern?
    For me it seems one and the same.
    Please explain me in detail. Expecting kind help.
    Thanks,
    Rahul
    Edited by: rahulb1 on Feb 26, 2008 5:07 PM

    rdoekes wrote:
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    As J2EE components are using JDNI to lookup for ejb interfaces,DataSources, JMS components, connections etc. isntead of writing all the lookup in many code piecess across the project, you write a service locator that gives you a centralized place to handle the lookup's. It's easier to maintain and to control such a setup.
    As you can see there's quite a big difference ;-)
    cya,
    Nail

  • Service Locator implementaion for PetStore

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    thanks

    Hi,
    This question was answered on the patterns interest list recently. The response is at
    http://swjscmail1.java.sun.com/cgi-bin/wa?A2=ind0301&L=j2eepatterns-interest&P=R5864
    hope that helps,
    Sean

  • Service locator

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    cpallab wrote:
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