Wednesday, 15 February 2017

OSB Interview Questions

1) What is Oracle Service Bus and Key features ?


2) What is difference between Oracle SOA Suite and OSB ?


3) What is Business Service ?

  • Business services are Oracle Service Bus definitions of the enterprise services that exchange messages during business processes.
  • Business service to connect to target system.


4) What is Proxy Service ?

  • It is a service in OSB which is exposed to source system or application.
  • A proxy service can route messages to multiple business services.


5) What is the difference between Business Service and Proxy Services ?


6) What is split join ?


Oracle Service Bus's advanced mediation feature, called Split-Join, helps you improve service performance by concurrently processing individual messages in a request. 

Oracle Service Bus's Split-Join feature lets you split a service payload, such as an order, into individual messages for concurrent processing. Concurrent processing, as opposed to sequential processing, greatly improves service performance. Split-Join achieves this task by splitting an input message payload into sub messages (split), routing them concurrently to their destinations, and aggregating the responses into one overall return message (join). This process of payload splitting and response aggregation is called a Split-Join pattern.



7) Types of Split-Joins?


There are two types of split join

1) Dynamic: It is used when we don't know the number of operation/services at design time. For example we have a online shopping site and don't know the number of orders. In this case we will use dynamic split join.

2) Static: It is used when we know the number of operations/services at design time.


8) What is throttling in OSB ?


  • Throttling, which lets you control the amount of message traffic to a business service, helps improve performance and stability by preventing message overload on high-traffic business services.
  • Throttling means we want to process certain messages in one time, then we need to set some parameters in OSB to do the required task.


9) What is Service pooling in OSB ?


In OSB we can group together more than one service so that whenever one service goes down, request will route to next available service and end user can continue his work without any interruption. 

10) How to call java functions in OSB ?


11) Can we invoke Restful service from OSB ?


Yes we can invoke Restful services in OSB. Follow the blog to know how to achieve this.

13) Can we use more than one route node in message flow ?


No, we can't we use more than one route node in proxy service message flow.

14) Can we use OWSM to secure OSB services ?


Yes we can use OWSM(Oracle Webservice Manager) to secure OSB service. Follow the blog to know how to achieve this.

15) How to perform Service Callout in OSB ?


We can use service callout,publish or Route node activity to call any service in OSB. 

16) What are the transformation resources available in OSB ?


It's always required to transform messages from one format to another. OSB provides XSLT and XQuery for the transformations.

17) How can you jump control from one stage to next stage without using if then else logic ?


You have to use Skip action at the end of the stage.

18) What is Customization File ?


Customization files are XML files and you can open these files in any editor and substitute the required environment values. 

In addition, you can search for specific environment values (that are not complex XML types) in Oracle Service Bus Console or in a customization file and replace them with the new values. You can fine-tune the scope of the search by filtering these environment values based on variable type or project. 


19) What is Message Context ?


All messages sent to and received by the proxy service are defined internally in the proxy service by a set of properties that holds the message data and meta-data related to that message. This set of properties is known as the Message Context (context) and is implemented using Context Variables. 

It is defined by an XML schema. Each Context Variable relates to a different property. Some Context Variables are predefined and others are user defined. The heart of the proxy service is the Message context. 

20) Is there any other way to connect to Database without using JCA adapters?

Yes we can use XQuery execute-sql() function to connect to database. But it is better to use JCA adapters.





No comments:

Post a Comment