Most Asked DevOps Interview Questions

151. What are the minimum requirements for POM?

The minimum. requirements for the POM file is Project root , Model Version, group ID, artifact ID and Version.
For example:
   <project>
          <modelVersion>1.0.0</modelVersion>
          <groupId>com.wiculty.app</groupId>
          <artifactId>wiculty-Learning-app</artifactId>
          <version>1</version>
   </project>

152. What are the features of Maven?

Here are some features listed:
Simple to Use: As The Maven is Conventional, it provides a project setting that is based on genuine Projects.
Fast: Create any project/module within a few Seconds.
Easy to Use: Maven commands are pretty straight forward and they are easy to understand.
Multiple Projects: Can manage more than one project at the same time.
Huge Library: As the Maven is a growing repository of libraries and metadata to use out of box. Can easily write plugins in Java or scripting languages.
Dependency Management: Automatic updating dependencies and transitive dependencies.

153. How to install Maven?

Maven is a open source build tool, it can download & install in any platform like ubuntu, windows, The steps are described below

• Download & Extract Maven
• Add JAVA_HOME and MAVEN_HOME to the list of Environment variables.
• Add the Environment Path in Maven Variable. (If OS is windows)
• Verify the maven installation by checking its version.

154. What does the mvn clean do?

The "mvn clean" command removes/cleans the target directory with all the previous build data before starting the new build.

155. Define Repository? What are the types of repositories?

Maven Repository is nothing but a directory where all the Jars and POM.XML files are stored. There are 3 types of repositories:
Local Repository: It is a local repository that will be created by maven, when the maven commands are executed. When you run maven command maven looks for dependencies first in the local repository. Which is your .M2 directory located in your $userhome
Central Repository: Maven community manages one repository on the web which is named as Central Repository. It contains a large number of libraries. When you run maven command maven looks for dependencies first in the local repository, if it is not there then by default maven looks in Central Repository.
Maven’s Central Repository url is "repo.maven.apache.org/maven2/"
Remote Repository: If needed dependency is not available in Manven’s Central Repository then it may be available in any other Remote location managed by some other organizations those repositories are called Remote repository. So manually defining libraries in pom is suggested because some of the Libraries may not be available in the Maven’s central repository.

156. Name the three Build cycles of Maven?

Here are the Three build cycles of maven listed below:
Clean:Cleans the artifacts created by prior builds
Default:Deals with the complete deployment of the application
Site:Generates site document(java document) for the project.

157. When does the maven use the External dependency concept?

Maven dependency management search for dependencies in local, central and remote in sequence, if there is no dependency present in any of these, then in this case it uses External dependency concept.

158. What is SNAPSHOT in Maven?

The SNAPSHOT is nothing but a current development copy of the project. In short, the working version of the project is a snapshot. For example, prior to version "1.0-release" there will be "1.0-Snapshot" version.

159. What is a transitive dependency in Maven?

Transitive dependency is like indirect dependency, suppose A depends on B and B depends on C. Then, A depends on both B & C but A is transitively dependent on C. And the good thing is Maven downloads transitive dependencies automatically.

160. What is all the information POM contains?

The POM contains the following Configuration Details like:

• Project Dependencies
• Plugins
• Goals
• Build Profiles
• Project Version
• Developers info
• Mailing List