Mulesoft Interview Questions

 Q1: What is Mule ?

A:Mule ESB (a.k.a. Mule) is a lightweight Java-based enterprise service bus (ESB) and integration platform that allows developers to connect applications together quickly and easily, enabling them to exchange data. Mule ESB enables easy integration of existing systems, regardless of the different technologies that the applications use, including JMS, Web Services, JDBC, HTTP, and more. Mulesoft online training

Q2: What is ESB ?
A: An enterprise service bus (ESB) is software architecture for middleware that provides fundamental services for more complex architectures. For example, an ESB incorporates the features required to implement a service-oriented architecture (SOA). In a general sense, an ESB can be thought of as a mechanism that manages access to applications and services (especially legacy versions) to present a single, simple, and consistent interface to end-users via Web- or forms-based client-side front ends.

Q3: What is Shared Context ?
A:Shared Context: Context is a temporary area which is created along with Service Message Object (SMO) in the Mediation Flows. Shared Context is a type of context which is present in the SMO. Shared Context is mainly used when we are using Aggregation process where we need to Iterate the BO for Certain times. Shared Context maintains Aggregation data between Aggregation (FanOut and FanIn) primitives. The Content (data) which is present in the shared context BO does not persist across Request and Response flows i.e The Data in the Shared Context which is used in Request flow can not be used again in Response flow.

Q4: What are Batch Jobs in Mule ESB ?
A: A batch job is a top-level element in Mule which exists outside all Mule flows. Batch jobs split large messages into records which Mule processes asynchronously in a batch job; just as flows process messages, batch jobs process records.
A batch job contains one or more batch steps which, in turn, contain any number of message processors that act upon records as they move through the batch job. During batch processing, you can use record-level variables (recordVars) and MEL expressions to enrich, route or otherwise act upon records. know more at Mulesoft training

Q5: What is Transient Context ?
A:Transient Context: Used for passing values between Mediation primitives within the current flow — either the request flow or the responses flow. The transient context cannot link requests and responses and hence cannot be used across. Used when you want to save an input message before a service invokes call (within a request or response flow). After the services invoke call, the next primitive can create another message by combining the service invoke response and the original message stored in the transient context.

6. What are the different endpoints available in Mule ESB?
Answer: Different types of Endpoints that are available in Mule are HTTP, JMS, IMAP, SMTP, and AJAX.

7. What are Inbound endpoints and Outbound endpoints in Mule ESB?
Answer: Inbound endpoints are defined as the message sources

8. What is the difference between Mule Connectors and Transports Mule ESB?
Answer: Transports are targeted towards a way of transporting data, i.e. a protocol like HTTP or reading/writing files. These are also defined as the general concepts and the other party that is behind such as a data channel and can be anything, a party with whom data can be exchanged, pure data sink or an own company.

9. What is the functionality of Fan-in and Fan-out?
Answer:
Fan-Out: We can use the Fan out primitive for firing the output terminal once (with the input message) or firing the output terminal multiple times. You can be using the Fan out in isolation or as part of a Fan-out and Fan in combination.
Fan-In: Fan In is always partnered with Fan-out in the same flow and acts as a decision point for when to continue for flow execution. It will receive a number of messages until a decision point is reached, at which the last message to be received is propagated to the output terminal. The Fan in primitive may only be used in combination with Fan-out.

10. What is the Difference between SDO and SMO?
Answer:
SDO: Service Data Object is simply defined as the representation of the Objects or variables.
SMO: The SMO model is defined as a pattern for using SDO Data Objects for representing the messages.

11. Why the Name Mule?
Answer: We should know that there is a lot of infrastructural work to be done before we can really start thinking about the implementation of any logic. So this infrastructural work is regarded or termed as “donkey work” as it is needed to be done for almost every project. A Mule is also simply referred to as a carrier of loading that is moving it from one place to another. The load here specialized in moving is our information of enterprise. know more at Mulesoft online course

12. What are the different types of Flow Processing Strategies?
Answer: There are various types of Flow Processing Strategies and they are as follows:

1. Asynchronous Flow Processing Strategy.
2. Custom Processing Strategy.
3. Thread Per Processing Strategy.
4. Queued Asynchronous Flow Processing Strategy.
5. Synchronous Flow Processing Strategy.
6. Non-blocking Flow Processing Strategy.
7. Queued Flow Processing Strategy.

13. What Are Available Esbs Apart From Mule?
Answer: The available Esbs apart from Mule are the entire major JEE vendors (BEA, IBM, Oracle, Sun) which are having an ESB in their catalog. It unremarkably has its basis on their middleware technologies and is generally the core of a much broader SOA product suite. There are also some of the commercial ESBs that have been built by the vendors not in the field of JEE application servers but like the ones from IONA Technologies, Progress Software, and Software AG.

14. Why is Mulesoft preferred than other ESB implementations?
Answer: Mule is referred to as lightweight but highly scalable which allows you to start small and connect more applications over the time. The ESB is capable of managing all the interactions between the applications and components transparently, regardless of whether they are existing in the same virtual machine or over the Internet regardless of the underlying transport protocol which is getting used.
Several commercial ESB implementations are used for providing the limited functionality or built on the top of an existing application server or messaging server, locking you into that specific vendor. Mule is vendor-neutral. So different vendor implementations can be plugged into it. You are never getting locked into a specific vendor when you are making use of the Mule.

15. What Is Filter In Mule?
Answer: Filters are defined as a powerful complement to the routers. Filters are providing the brains to routers needed for making the smart decisions about what to do with messages in transit. Some filters go as far as deeply analyzing the message content for a particular value on which their outcome will usually be based. know more at Mulesoft online training from India

16. Name the different types of Web services?
Answer: There are basically two types of web services which are as follows:

• SOAP web services.
• RESTful web services.

17. What is the difference between Stop and fail?
Answer:
Stop: Stop is used to stop a particular path in the flow, without generating an exception.
Fail: It is used to generate a failure in the flow.

18. How to add classes/jars to the Mule classpath?
Answer: By making use of the MULE_LIB variable (generally set in the run script).
To include JAR file(s) in a mule classpath, declare each dependent jar file in the MULE_LIB entry.

19. What is Mule Data Integrator?
Answer: Mule has released a data integrator tool; it is referred to as a visual mapping tool which supports XML mappings, flat-file, java object, etc. Coding complex mappings are the mappings that can be very tedious and additionally difficult for maintaining, the mule data integrator with the help of the drag and drop facilities makes the building and maintaining of the mappings very simple and easy.
The mapping is done in the eclipse (plugins are required) and getting executed on a data integrator runtime which sits on the top of Mule ESB – this is a required license. know more at Mulesoft online training in Hyderabad

20. What is a Mule UMO?
Answer: A Mule UMO is referred to as a Universal Message Object.
UMO is now a legacy term. These are the Components which are now termed or referred to as Service Components.