Fold String.format to interpolated strings.
At present time plugin fold to interpolated strings only the string concatenations. It's will be impress to fold String.format too.
For example this:
return String.format("Start in %d days", days);
to this:
return "Start in $days days";
Didn't realize this wasn't available yet. String.format would definitely be a nice addition; however, there is a popular Android logging library called Timber that is a fusion between Logcat and String.format. If you support String.format, it seems that support of Timber would be plausible.
However, this might bring up the question of if there should be an AdvancedAndroidFolding library that would work together as this is specific to Android code and not necessarily Java.
https://github.com/JakeWharton/timber
Original Timber code example:
Timber.i("A button with ID %s was clicked to say %s.", button.getId(), button.getText());
Could be shortened to...
Timber.i("A button with ID ${button.id} was clicked to say ${button.text}.");
Some Java (as in 'non-Android') logging frameworks also support "format pattern" feature.
For example, in SLF4J: logger.error("one two three: {} {} {}", "a", "b", "c", new Exception("something went wrong"));
So folding support for logging would be useful for "plain Java" code too.