Annotation Interface CommandLine.Mixin

Fields annotated with @Mixin are "expanded" into the current command: @Option and @Parameters in the mixin class are added to the options and positional parameters of this command. A CommandLine.DuplicateOptionAnnotationsException is thrown if any of the options in the mixin has the same name as an option in this command.

The Mixin annotation provides a way to reuse common options and parameters without subclassing. For example:

  class HelloWorld implements Runnable {

 // adds the --help and --version options to this command
  @Mixin
  private HelpOptions = new HelpOptions();
 
  @Option(names = {"-u", "--userName"}, required = true, description = "The user name")
  String userName;
 
  public void run() { System.out.println("Hello, " + userName); }
 
}
// Common reusable help options.
class HelpOptions {
 @Option(names = { "-h", "--help"}, usageHelp = true, description = "Display this help and exit")
  private boolean help;
 
  @Option(names = { "-V", "--version"}, versionHelp = true, description = "Display version info and exit")
  private boolean versionHelp;
 
}