To display line numbers, right-click on the left margin and click on the
checkbox labeled Show Line Numbers .
At this point we are ready to debug our application, which we can do by simply
right-clicking on our project and selecting Debug . Doing this causes our application
to be deployed and executed as in debug mode.
We need to test our application as usual in order to get to the point where it is failing.
In our example application we simply need to execute the code until it attempts to
persist our JPA entity.
Looking at the editor, we will see that the line containing the breakpoint is now
highlighted in green, plus an arrow has been placed on the left side margin.