In the upcoming 2.6.0 release of RSyntaxTextArea, I’m adding a feature that I like that’s in IntelliJ IDEA.
When the caret is on a bracket, and the matched bracket is “above” the current one and scrolled off of the screen, RSTA will now render the line containing the parent bracket in a small popup window after a small delay:
This allows you to quickly see the scope of the block your caret is around, without having to scroll up in the editor. If the line containing the matching brace is only whitespace and the curly brace, the line prior to that one will be in the tool tip as well (for code written in K&R style, for example).
This feature is enabled by default, but can be disabled by calling textArea.setShowMatchedBracketPopup(false).