How to build jobs in jenkins when a change is pushed to Bitbucket

Bitbucket plugin is designed to offer integration between Bitbucket and Jenkins.
It exposes a single URI endpoint that you can add as a WebHook within each Bitbucket project you wish to integrate with. This single endpoint receives a full data payload from Bitbucket upon push (see their documentation), triggering compatible jobs to build based on changed repository/branch.
Step 1 – Install “Bitbucket Plugin” at your Jenkins
Step 2 – Add a normal Post as Hook to your Bitbucket repository (Settings -> Hooks) and use following url:
https://YOUR.JENKINS.SERVER:PORT/bitbucket-hook/
and if you have setup authentication on jenkins then URL must be like
https://USERNAME:PASSWORD@YOUR.JENKINS.SERVER:PORT/bitbucket-hook/
Step 3 – Configure your Jenkins project as follows:
Step 4 – Under build trigger enable Build when a change is pushed to BitBucket
Step 5 – under Source Code Management select GIT; enter your credentials and define Branches to build (like **feature/*)
Note 1 – Make sure to include the slash (‘/’) on the end of the URL or the hook won’t work.
Note 2 – Please read the BitBucket Plugin info page as well https://wiki.jenkins.io/display/JENKINS/BitBucket+Plugin
Reference 1  
Reference 2 – Login issues with Jenkins url
Rajesh Kumar