Package picocli

Class CommandLine.HelpCommand

  • All Implemented Interfaces:
    java.lang.Runnable, java.util.concurrent.Callable<java.lang.Integer>, CommandLine.IHelpCommandInitializable, CommandLine.IHelpCommandInitializable2
    Enclosing class:
    CommandLine

    public static final class CommandLine.HelpCommand
    extends java.lang.Object
    implements CommandLine.IHelpCommandInitializable, CommandLine.IHelpCommandInitializable2, java.lang.Runnable, java.util.concurrent.Callable<java.lang.Integer>
    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 Summary

      Constructors 
      Constructor Description
      HelpCommand()  
    • Method Summary

      All Methods Instance Methods Concrete Methods Deprecated Methods 
      Modifier and Type Method Description
      java.lang.Integer call()  
      void init​(CommandLine helpCommandLine, CommandLine.Help.Ansi ansi, java.io.PrintStream out, java.io.PrintStream err)
      Deprecated.
      void init​(CommandLine helpCommandLine, CommandLine.Help.ColorScheme colorScheme, java.io.PrintWriter out, java.io.PrintWriter err)
      Initializes this object with the information needed to implement a help command that provides usage help for other commands.
      void run()
      Invokes usage for the specified command, or for the parent command.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • 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 java.lang.Runnable
      • call

        public java.lang.Integer call()
        Specified by:
        call in interface java.util.concurrent.Callable<java.lang.Integer>
      • init

        @Deprecated
        public void init​(CommandLine helpCommandLine,
                         CommandLine.Help.Ansi ansi,
                         java.io.PrintStream out,
                         java.io.PrintStream err)
        Deprecated.
        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
      • init

        public void init​(CommandLine helpCommandLine,
                         CommandLine.Help.ColorScheme colorScheme,
                         java.io.PrintWriter out,
                         java.io.PrintWriter 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.IHelpCommandInitializable2
        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.
        colorScheme - the color scheme to use when printing help, including whether to use Ansi colors or not
        out - the output writer to print the usage help message to
        err - the error writer to print any diagnostic messages to, in addition to the output from the exception handler