An OpenJDK language enhancement proposal suggests the use of hyphenated keywords to denote new features, with the goal of ensuring compatibility and readability as suitable keyword tokens become increasingly scarce.
The draft Java enhancement proposal for keyword management notes that new features in the Java language often require new keywords, but new keywords risk breaking existing programs. For balancing readability and compatibility, a new type of keyword could be used, namely a hyphenated keyword that is a compound of identifiers and pre-existing keywords. Examples cited were non-final, break-with, and short-circuit.
