IntelliJ - No sources found

When I implement a method in a class, and I implement all methods to override, I get things like:

@Override public void setMinAndMaxCornerValues(int i, int i2, int i3, int i4, int i5, int i6, int i7, int i8)

These argument names don't help. I expect: int minXIndex, int minX, int minYIndex, int minY, int maxXIndex, int maxX, int maxYIndex, int maxY)

.

If I choose not very useful and do go to> super method , then I see the following (with all methods with "missing" argument names):

When I click Attach Sources ... it goes to the jar file. But selecting it and hitting ok doesn't change anything.

How to solve this problem?

In case it matters, I created this jar file. ...