78450001 SOA 11g Interview Questions

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    SOA 11g Interview Questions

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    This Document is only a SAMPLE

    We have published only a few slides on Scribd, out of our 107 total slides You can buy this complete document for $39 by sending an email to [email protected] You can buy this whether you are in US, UK, India, Australia or anywhere else Check out our website http://soatraining.hpage.com for more exciting information onSOA2

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    Contents (total 102 questions)

    SOA Installation New features introduced in 11g What is SCA, its benefits BPEL Multiple Receive Activities BPEL How to Call Java BPEL WSDL Concepts BPEL Type ofvariables BPEL Optional responses BPEL Multiple Operations BPEL Correlation Sets BPEL No Dehydration BPEL Transactions

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    Contents (total 102 questions)

    My Role PartnerRole difference Multiple Service Bindings Various options for Scheduling SOA composites Preferences SOA Infra Key Tables Read files in binary format Fault Policy Framework (16 questions) Java actions in Fault policy Fwk FileAdapter (13 questions) DB Adapter (8 questions) JMS Adapter (1 question) Transaction (9 questions) Scenario Based Questions (12 questions)4

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    SOA General Questions1. 2. 3. 4.

    What is SOA? Why is it so popular Explain SCA. What is the benefit it brings totable How can you deploy a composite without JDeveloper What are some of the newfeatures that have been introduced in SOA 11g

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    SOA General AnswersWhat is SOA. Why is it so popularSOA is a design methodology that advocates exposing of product functionality asservices. This enables to

    Reuse functionality Have loose coupling between functionalities Abstract implementation Allow multiple protocols to talk to each other

    SOA isnt a solution to world hunger ! Nor is it:

    A specific Technology The Ultimate answer to reuse A New name for EAI A New wayto do RPC

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    SOA Installation AnswersWhat is SCA SCA provides a programming model That model allows Creating service components written with a wide range of technologies Assembling the service components into a SOA composite application Please read the presentation on SOAArchitecture for complete details.

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    SCA BenefitsSCA simplified the entire lifecycle DevelopmentJDev can be used to develop all components.

    DeploymentAll components are grouped together in a composite and during compilation, we get a single file called SAR SAR can be versioned as one, deployed as one and managed as one

    MonitoringEM allows to trace the entire flow, giving ability to drill down into componentsof a composite8

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    What are some of the new features that have been introduced in SOA 11g

    SCA Adapter properties can be set easily. Direct support built in JDeveloper Single console to manage everything, the Enterprise Manager End-to-end flow tracking possible using ECID Business rules can be authored in JDeveloper itself Mediator is versionable EDN Config Plans9

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    SCA

    What is the difference between Service component, Service binding and referencebinding Can a composite have multiple service bindings

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    SCAWhat is the difference between Service component, Service binding and referencebinding

    Service components are the building blocks that you use to construct a SOA composite application. Examples - BPEL, Human Task, Business Rules, Mediators, Spring. Binding component establish a connection between a SOA composite and the external world. They are categorized as Service binding component and Reference binding components.Service binding components provide the entry point to the composite Reference binding components provides access to the external service in the outside world. Examples include JCA adapters, HTTP binding, Direct binding etc.

    Can a composite have multiple service bindings

    Yes, there can be multiple service bindings for a composite

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    Fault Policy Framework

    What needs to be done (steps) If a bpel has catch and we also have policies, which will take precedence Can we handle xpath errors. Can we handle errors from Asynchronous PL. Can we throw errors from bpel explicitly (using throw) and expectfwk will handle them OR Can the framework handle custom faults? If no, How we can make it handle custom faults. Is it possible to handle database faults usingfwk What are the various actions possible How can we use the fwk to send email12

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    Fault Policy Framework

    What needs to be done (steps)

    The policies are setup per application. Define a bindings file in the application. Create policy file in the application and define what type of faults we wantto catch and what actions need to get executed

    If a bpel has catch and we also have policies, which will take precedence

    The policies take precedence.

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    Threading Questions

    Explain the threading model in SOA Suite OR What happens when a one way messagecomes to SOA Server and What happens when a sync message comes

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    Threading Questions

    A One-way invocation offers several advantages in terms of scalability, becausethe service engines thread pool (invoker threads) executes when a thread is available. However, the disadvantage is that there is no guarantee that it executes immediately. How to ensure that the one way invocations are synchronous

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    ThreadingAnswers

    If you require a synchronous-type call based on a one-way operation, then you can use the onewayDeliveryPolicy property Specify this in composite.xml The following values are possible.async.persist: Messages are persisted in the database hash map. async.cache: Messages are stored in memory. sync: Direct invocation occurs on the same thread.

    This allows us to trade-off reliability of delivery and coupling with the clientfor speed of delivery. Using the sync option offers the best performance, but the requestor will perceive that it took longer to post the message due to the increased coupling between the requestor and the target. Similarly, using the async.cache option reduces the performance overhead of storing the message in memory. However, if the server fails before the message is processed, it will be lostas it is stored in memory.

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    WSDL

    Can you describe a WSDL file Which element of WSDL gives the location of service

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    Adapters File Adapter

    What is JCA How will you set the filename dynamically for a write file adapter How will you find the size of the file read How will you change the directory atruntime How will you change the directory through EM console (not at runtime, not at design time either, but rather after the process has been deployed) If a message gets rejected, where does it go Can the file/ftp adapter poll multiple directories What is distributed polling wrt the file/ftp adapter18

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    Adapters DB Adapter

    You have three physically different databases, one for each geography APAC, US, Europe. You are getting customer data. Based on the location, you want to insertinto the appropriate database. How can this be achieved. Discuss possible approaches and benefits and drawbacks

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    Adapters DB Adapter: AnswersWe can use the following approaches 1. Use a mediator and do content based routing. Each DB has its JNDI set 2. Use a bpel, and use dynamic partnerlink. The DBparameters are passed as input (or read from some source like DVM) Approach 1 Pros 1. Easy to change rules 2. Easy to add new targets 3. User id passwords dont get exposed as we can use JNDI Approach 1 Cons 1. If we need to add a new target,it cannot be done dynamically. We need to manually go and add a new routing rule Aproach 2 Pros 1. A new target database can be referred to very easily, as we justneed to change the inputs Approach 2 Cons 2. UserId and pwd is exposed, unlessyou write java code that retrieves user id and pwd from jndi 3. If you use the java code, then you need to use

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    Transactions

    If A calls B, both BPEL composites, do they share a transaction How can you makeB share a transaction What happens if A inserts data in DB, then calls B synchronously, B inserts a row in DB and then throws a remote exception What happens if A inserts data in DB, then calls B synchronously, B shares the transaction with A, B inserts a row in DB and then throws a remote exception21

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    Transactions : Answers

    If A calls B, both BPEL composites, do they share a transactionThe default behavior is that they dont. B shall create its own transaction.

    How can you make B share a transactionIt can be changed by putting transaction=required in Bs composite.xml. Default istransaction=requiredNew

    What happens if A inserts data in DB, then calls B synchronously, B inserts a row in DB and then throws a remote exceptionA handles the error. Note, B was in a different transaction than A. So B rolls back as it has a unhandled exception. So insert of A stays, insert of B is rolledback.

    What happens if A inserts data in DB, then calls B synchronously, B shares the transaction with A, B inserts a row in DB and then throws a remote exceptionA handles the error. Note, B was in a different transaction than A. So B rolls back as it has a unhandled exception. So insert of A stays, insert of B is rolledback.

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    Transactions

    What happens if A inserts data in DB, then calls B synchronously, B inserts a row in DB and then throws a rollback exception What happens if A inserts data in DB, then calls B synchronously, B shares the transaction with A, B inserts a rowin DB and then throws a rollback exception If a DB adapter inserts into DB, thenan unhandled error is thrown, does the DB insert rollback? If a DB adapter inserts into DB, then there is a dehydration point, then an unhandled error is thrown, does the DB insert rollback?

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    More Questions

    Where do you see logs How to see messages in JMS You have a java class. How canyou use it in bpel program

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    Scenario Question - 1

    I have 5 departments who want to communicate Customer data. Each team is interested in some common attributes and some attributes that are specific to their application. The provider application serves only the relevant fields to the departments. What kind of problems do you foresee and what can be a solution.

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    Scenario Question - 1

    As each system requires a different set of data, there would be a problem of developing large number of transformations if we start connecting each system to every other system. There would be n(n-1)/2 transformations required Using a canonical data model to convert an application specific message to a common message can solve the issue. See http://www.soapatterns.org/canonical_schema.php for details about this SOA design pattern26

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    Scenario Question - 2

    I want to design a system that would process orders during the night and despatch them to the suppliers. However, I want the system to be capable of accepting orders all throughout the day. What kind of architecture do you propose

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    Scenario Question - 2

    We need to design a system with asynchronousity built into it. We can go for storing the messages in queues. However EDN would be an even better alternative

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    This Document is only a SAMPLE

    We have published only a few slides out of our 107 total slides You can buy thiscomplete document for $39 by sending an email to [email protected] You can buythis whether you are in US, UK, India, Australia or anywhere else Check out ourwebsite http://soatraining.hpage.com for more exciting information on SOA29

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