Eclipse warning: "contains markers which may be removed by Sort Members" -- markers?

Question

Sometimes when using 'Source > Sort Members' in Eclipse, I get this warning message. I am assuming "markers" are referring to these, but what is making them?

I don't manually make them. Could a plugin, FindBugs or PMD, be making these markers? (I still get the warning even when there are no current FindBugs or PMD warnings.)

I never visually see any indication of these "markers". Is it safe to just ignore this warning?

Answer 1

Markers can be Errors, Warnings, Bookmarks, Todo tasks and anything else that plugins care to create. They are attached to a file and can specify a position in the file - the sort may have to discard them.

You can see all markers in the Markers view (Window > Show View > Other... > General > Markers). Errors and warnings are shown in the Problems view, Bookmarks in the Bookmarks view and Todo in the Tasks view.

Most markers on a file are also indicated in the vertical ruler on the left of the editor for the file.