Writing listeners in JIRA
Listeners are very powerful features in JIRA. JIRA has a mechanism of throwing events whenever something happens on an issue, such as when creating an issue, updating an issue, progressing on the workflows, or in similar events. Using listeners, we can capture these events and do special things based on our requirements.
There are two different ways using which listeners can be implemented in JIRA. The old way of doing it is to extend the AbstractIssueEventListener class which in turn implements the IssueEventListener interface. The AbstractIssueEventListener class captures the event, identifies its type, and delegates the event to the appropriate method where it is handled. To write a new listener, all we need to do is to extend the AbstractIssueEventListener class and override the methods of interest!
The new way of doing it is to use the atlassian-event library. Here, we register the listener in the plugin descriptor and implement the listener with the help of...