Jenkins - set up multiple pipelines for subprojects with in a project

I have a project structure like this -

Main Project

  • pom.xml
    Sub project A
    - pom.xml
    - Jenkinsfile
    Sub Project B
    - pom.xml
    - Jenkinsfile
    Sub Project C
    - pom.xml
    - Jenkinsfile
    Sub Project D
    - pom.xml
    - Jenkinsfile

Now i have created the pipeline for each sub project in Jenkins and i am pulling the project using pom.xnl from Main project so it is downloading all the sub projects and building them in each pipeline. But I would want to checkout and build each sub project individually through its own pipeline in Jenkins

What is the best way to achieve this? How can i set this kind of pipeline in Jenkins?