Package picocli

Class CommandLine.HelpCommand

  • All Implemented Interfaces:
    Runnable, CommandLine.IHelpCommandInitializable
    Enclosing class:
    CommandLine

    public static final class CommandLine.HelpCommand
    extends Object
    implements CommandLine.IHelpCommandInitializable, Runnable
    Help command that can be installed as a subcommand on all application commands. When invoked with a subcommand argument, it prints usage help for the specified subcommand. For example:
    
     // print help for subcommand
     command help subcommand
     

    When invoked without additional parameters, it prints usage help for the parent command. For example:

    
     // print help for command
     command help
     
    For internationalization: this command has a --help option with descriptionKey = "helpCommand.help", and a COMMAND positional parameter with descriptionKey = "helpCommand.command".
    Since:
    3.0
    • Constructor Detail

      • HelpCommand

        public HelpCommand()
    • Method Detail

      • run

        public void run()
        Invokes usage for the specified command, or for the parent command.
        Specified by:
        run in interface Runnable
      • init

        public void init​(CommandLine helpCommandLine,
                         CommandLine.Help.Ansi ansi,
                         PrintStream out,
                         PrintStream err)
        Initializes this object with the information needed to implement a help command that provides usage help for other commands.
        Specified by:
        init in interface CommandLine.IHelpCommandInitializable
        Parameters:
        helpCommandLine - the CommandLine object associated with this help command. Implementors can use this to walk the command hierarchy and get access to the help command's parent and sibling commands.
        ansi - whether to use Ansi colors or not
        out - the stream to print the usage help message to
        err - the error stream to print any diagnostic messages to, in addition to the output from the exception handler