How to customize icons near the scrollbar in the Eclipse Java editor?

The Eclipse java editor displays small colored rectangle icons just to the right of the scrollbar to indicate lines with //TODOs, deprecated stat开发者_运维问答ements, etc. One of the most useful shows the other occurrences of a currently selected variable, but the color of this one is practically the same as the background.

What are these icons called and how can I customize the colors?

Like a lot of things in Eclipse, it's easy, once you know what something is called ;-)

In the Preferences tree, that right strip is the "Overview Ruler". Here's some of my notes:

Display of Task and Bookmarks
    Preferences / General / Editors / Text Editors / Annotations
    Show in:
        Vertical Ruler = left edge icons, in sight of current scroll position
        Overview Ruler = right edge colored blocks, relative to overall file
        Text as = markup the actual text