ESB Interview Questions And Answers

ESB Interview Questions And Answers prepared from Codingcompiler experts. These WSO2 ESB Interview Questions were asked in various interviews conducted by top multinational companies across the globe. We hope that these interview questions on WSO2 ESB will help you in cracking your next job interview. All the best and happy learning.

In this article, you’ll learn

ESB Interview Questions
ESB Interview Questions And Answers
Advanced ESBCognos interview Questions And Answers

ESB Interview Questions

  1. What do you understand by ESB?
  2. List the different primitives that are constantly used in Mediation.
  3. How to find if project needs ESB?
  4. What do you understand by Shared Context?
  5. ESB IS HERE TO STAY, BUT IT WILL EVOLVE?
  6. How to select an ESB?
  7. Different ESBs in the market? You have worked on which?
  8. What can be used to implement a loop in mediation?
  9. What method can be applied to change the runtime using mediation primitive?
  10. What are the advantages of using an ESB ?

ESB Interview Questions And Answers

Q. What do you understand by ESB?

Answer: An Enterprise Service Bus (ESB) is a programming language for engineering especially for middleware that gives major administrations to progressively complex models. For instance, an ESB incorporates the highlights requirements to actualize a service-oriented architecture (SOA). In simple terms, an ESB can be thought of as a component that oversees access to applications and administrations (particularly inheritance variants) to introduce a solitary, straightforward, and steady interface to end-clients through Web-or structures based customer side front end.

Q. List the different primitives that are constantly used in Mediation.


Answer: Some of the commonly used primitives in Mediation include the following:

  • Message Filter
  • Type Filter
  • Endpoint Lookup
  • Service Invoke
  • Fan – out
  • Fan – in
  • XSLT
  • BO Map

Q. How to find if project needs ESB?


Answer: ESB implementation is not suitable for all projects. Proper analysis should be done if the use of ESB will really benefit the project. Some of the points to be considered while analyzing the need of ESB are as follows-

  • If project requires integrating 3 or more applications/services. If the need is to communicate between 2 applications, using point-to-point integration would suffice.
  • If the project would need to be scaled in future where it might be needed to interact with more services in future. Not all projects need this as they may perform not that big a task.
  • If the project needs message routing capabilities such as forking and aggregating message flows. Such features are not required by all projects.
  • Is the architecture of what is to be achieved clear. Its much better to do simple POCs integrating small parts to evaluate the benefits.
  • Most ESBs are a costly affair. Does the project budget allow use of ESB.

Q. What do you understand by Shared Context?

Answer: It is a setting that is a brief territory, which is made alongside the Service Message Object (SMO) in Mediation Flows. Shared Context is a kind of setting which is available in the SMO. It is essentially utilized when we are utilizing Aggregation process where we have to iterate the BO occasions. Shared Context keeps up Meditation information between Meditation (Fan – Out and Fan – In) primitives. The Content that is available in the common setting BO does not hold on crosswise over Request and Response streams. For example, The Data in the Shared Context, which is utilized in Request stream can’t be utilized again in Response stream.

Q. ESB IS HERE TO STAY, BUT IT WILL EVOLVE?

Answer: While there are overlapping functions between ESB and SOA fabric, we believe these technologies are more complements than competitors. Many organizations will use SOA fabric as the backbone for composite application development while connecting to an ESB as the backbone for integration and event-driven/process-driven SOA.

Over the next three to five years, we expect to see coalescing of some of the technology components supporting fabric and ESB. This will be great, because how many messaging infrastructures, registries, repositories, and management tools does an organization really need? Since both technologies have service-oriented underpinnings with standards-based interfaces, any changes to the underlying implementations (if done correctly) should be non-invasive to the consumers.

Advanced ESB interview Questions And Answers

 Q.  How to select an ESB?

A: 

  • Usability: How complicated is the installation process? The learning curve of the ESB should not be long.
  • Maintainability: How to monitor the product? If any GUI terminal is available for monitoring the services.
  • Community- Is there active community for the ESB. Various discussion forums, tutorials etc.
  • Enterprose Support- Is the product support reliable. What services are available.
  • Flexibility- Can the ESB be configured to meet the business requirements.
  • Reliability- The reliablity of the ESB. Its current users and various case studies if available.
  • Cost- The cost of the ESB. Its Licence policies. Support cose. etc

Q. Different ESBs in the market? You have worked on which?

Answer: There are various ESB’s available in the market. Some are opensource, some licenced

1. Talend

2. Mule ESB

3. JBoss Fuse ESB

Q.  What can be used to implement a loop in mediation?

Answer: In order to implement a loop into mediation, one needs to use the “Fan – in” and “Fan – out” primitive.


Q. What method can be applied to change the runtime using mediation primitive?

Answer: In order to apply changes to the runtime during mediation primitive, promotable properties such as in ESB training Bangalore is generally utilized. One can always install it during the process of development as well. After which a runtime change can be applied without the need for restarting the server.

Q. What are the advantages of using an ESB ?

Answer: 

  • It provides a way for endpoints to connect to each other without having to directly talk to each other. It simplifies the communications for the endpoints as they only have to conform to a standard communication interface, the bus.
  • An ESB provides a single place to get some key endpoint metrics: frequency, availability, and performance.
  • An ESB tends to provide more than one communication interface. However, a developer-only needs to choose the easiest one to get and receive the data from the bus.

Q. What configurations are required for the implementation of JDBC Adapter?

Answer: In order to implement JDBC Adapter, a data source is created that needs to be configured alone with DB. Once the security check is completed then the initialized security is finally authenticated.

Q. Differentiate between SDO and SMO

Answer: SDO is an acronym for Service Data Object, which is a representation of any variable or an object. While on the other hand, SMO is a model that follows a particular pattern for utilizing the SDO objects in order to represent data messages.

Q. What methodology is adapted to add jars/ classes into the Mule classpath?

Answer: In order to add jars or classes into the Mule classpath, the following procedure is followed:

  • Use the MULE_LIB variable (for the most part set in the run content)
  • To incorporate JAR file(s) in a Mule class way, announce every needy container document in the MULE_LIB section.
  • For spring asset, if the XML bean announcement is put inside a venture, incorporate the task JAR record in the class way as well (i.e., if excluded, Mule will toss a **.xml not found on the class way)

Q. What do you understand by the term Mule Data Integrator?

Answer: Mule has discharged an information integrator apparatus, it is a visual mapping device that underpins level document, java object, XML mappings, and so forth. Coding complex mappings can be dull and hard to keep up; the Mule information integrator with intuitive offices makes constructing and keeping up mappings basic. The mapping is done in overshadowing (modules required) and executed on an information integrator runtime which sits over Mule ESB – this requires a permit.

Q. What are ESB Integration core principles?

Answer: 

  •  Orchestration-Composing several existing fine-grained components into a single higher order composite service. This can be done to achieve appropriate “granularity” of services and promote reuse and manageability of the underlying components. Transformation-Data transformation between canonical data formats and specific data formats required by each ESB connector.
  • Transportation-Transport protocol negotiation between multiple formats (such as HTTP, JMS, JDBC).
  • Mediation-Providing multiple interfaces for the purpose of a) supporting multiple versions of a service for backwards compatibility or alternatively, b) to allow for multiple channels to the same underlying component implementation. This second requirement may involve providing multiple interfaces to the same component, one legacy interface (flat file) and one standards compliant (SOAP/XML) interface.
  • Non-functional consistency-For a typical ESB initiative, this can include consistency around the way security and monitoring policies are applied and implemented.

Q.  What do you understand by Web service API?

Answer: API is an acronym for Application Programming Interface. It is generally used to write codes by third parties in order to interface with other systems. While, a Web Service is a type of API that constantly operates over HTTP like SOAP, SMTP, etc.


Q, What are the different strategies involved in Flow Processing?


Answer: The different strategies involved in flow processing include:

  • Queued Flow Processing Strategy
  • Synchronous Flow Processing Strategy
  • Thread Per Processing Strategy
  • Custom Processing Strategy

Q. Is an ESB an Architecture or a Product?

Answer: A big question in the ESB space is, “Is an ESB an architecture or a product?” On the surface, this question seems a little strange, because we would contend that all products, especially ones as critical as application infrastructure, should be designed and implemented from an architectural blueprint. So, at a first pass, we say “both.” But the underlying point here is that some large vendors (IBM for one) that have integration and application infrastructure solutions (but not distinct enterprise service bus solutions) are saying that the ESB is an architecture, or design pattern, from which an end user can assemble an ESB, using his current application infrastructure and integration products.

While this is true an end user can roll his own, the question then becomes, “Does that make sense?” Only the individual organization can answer that, considering its current investments, initiatives, skills, and risk tolerances. For the majority of organizations, the answer will be “no,” especially if production-quality ESB solutions are readily available.So, as a general statement, we say that an ESB is a product, which evolves from an architecture.

Q. What are the different strategies involved in Flow Processing?

Answer: The different strategies involved in flow processing include:

  • Queued Flow Processing Strategy
  • Synchronous Flow Processing Strategy
  • Thread Per Processing Strategy
  • Custom Processing Strate

Q. What are the features of ESB?

Answer: Features of ESB

  • Message Transformation Service
  • Web security services
  • Services regarding message routing
  • Service containers

Q. What do you understand by the term Mule Data Integrator?

Answer: Mule has discharged an information integrator apparatus, it is a visual mapping device that underpins level document, java object, XML mappings, and so forth. Coding complex mappings can be dull and hard to keep up; the Mule information integrator with intuitive offices makes constructing and keeping up mappings basic. The mapping is done in overshadowing (modules required) and executed on an information integrator runtime which sits over Mule ESB – this requires a permit.

Related Interview Questions

  1. Core Java Interview Questions
  2. JSF Interview Questions
  3. JSP Interview Questions
  4. JPA Interview Questions
  5. Spring Framework Interview Questions
  6. Spring Boot Interview Questions
  7. Core Java Multiple Choice Questions
  8. 60 Java MCQ Questions And Answers
  9. Aricent Java Interview Questions
  10. Accenture Java Interview Questions
  11. Advanced Java Interview Questions For 5 8 10 Years Experienced
  12. Core Java Interview Questions For Experienced
  13. GIT Interview Questions And Answers
  14. Network Security Interview Questions
  15. CheckPoint Interview Questions
  16. Page Object Model Interview Questions
  17. Apache Pig Interview Questions
  18. Python Interview Questions And Answers
  19. Peoplesoft Integration Broker Interview Questions
  20. PeopleSoft Application Engine Interview Questions

Leave a Comment