### Question:
ExitCommand implements Command { @Override public Usage usage() { return new Usage("exit"); } ExitCommand(Shell shell); @Override String name(); @Override Usage usage(); @Override void run(Line line);  }### Answer:
@Test public void testUsage() { ExitCommand command = new ExitCommand(new Shell()); Usage usage = command.usage(); assertThat(usage.synopsis(), is("exit")); assertThat(usage.options().size(), is(0)); }