public final class Prompt

Questions a command asks the person running it:

String name = Prompt.text("Project name", "demo");
String db = Prompt.select("Database", Arrays.asList("PostgreSQL", "MySQL", "SQLite"));
List<String> features = Prompt.multiSelect("Features", Arrays.asList("auth", "mail", "jobs"));
String token = Prompt.password("API token");
if (!Prompt.confirm("Create it?", true)) {
    return 1;
}

On a terminal each question is answered key by key: a text prompt edits in place (arrows, Home, End, Ctrl-U, Ctrl-W), a selection list moves with the arrows and filters as you type, a multiple selection toggles with Space. The question then collapses to one line showing the answer.

When standard input or output is not a terminal – a script piping answers in, a CI job – the same calls read one line per question, so a tool stays scriptable: a selection takes a number or the label, a multiple selection a comma-separated list of either, a confirmation y or n, and an empty line takes the default. End of input answers the default where there is one.

Ctrl-C, Escape, or end of input with no default throw Cancelled; a command run through CommandLine that lets it propagate exits with CANCELLED_EXIT_CODE, the code a shell gives an interrupted command.