Module info.picocli
Package picocli

Annotation Type CommandLine.Command


  • @Retention(RUNTIME)
    @Target({TYPE,LOCAL_VARIABLE,FIELD,PACKAGE,METHOD})
    public static @interface CommandLine.Command

    Annotate your class with @Command when you want more control over the format of the generated help message. From 3.6, methods can also be annotated with @Command, where the method parameters define the command options and positional parameters.

     @Command(name              = "Encrypt", mixinStandardHelpOptions = true,
            description         = "Encrypt FILE(s), or standard input, to standard output or to the output file.",
            version             = "Encrypt version 1.0",
            footer              = "Copyright (c) 2017",
            exitCodeListHeading = "Exit Codes:%n",
            exitCodeList        = { " 0:Successful program execution.",
                                    "64:Invalid input: an unknown option or invalid parameter was specified.",
                                    "70:Execution exception: an exception occurred while executing the business logic."}
            )
     public class Encrypt {
         @Parameters(paramLabel = "FILE", description = "Any number of input files")
         private List<File> files = new ArrayList<File>();
    
         @Option(names = { "-o", "--out" }, description = "Output file (default: print to console)")
         private File outputFile;
    
         @Option(names = { "-v", "--verbose"}, description = "Verbose mode. Helpful for troubleshooting. Multiple -v options increase the verbosity.")
         private boolean[] verbose;
     }

    The structure of a help message looks like this:

    • [header]
    • [synopsis]: Usage: <commandName> [OPTIONS] [FILE...]
    • [description]
    • [parameter list]: [FILE...] Any number of input files
    • [option list]: -h, --help prints this help message and exits
    • [exit code list]
    • [footer]
      • aliases

        String[] aliases
        Alternative command names by which this subcommand is recognized on the command line.
        Returns:
        one or more alternative command names
        Since:
        3.1
        Default:
        {}
      • subcommands

        Class<?>[] subcommands
        A list of classes to instantiate and register as subcommands. When registering subcommands declaratively like this, you don't need to call the CommandLine.addSubcommand(String, Object) method. For example, this:
         @Command(subcommands = {
                 GitStatus.class,
                 GitCommit.class,
                 GitBranch.class })
         public class Git { ... }
        
         CommandLine commandLine = new CommandLine(new Git());
         
        is equivalent to this:
         // alternative: programmatically add subcommands.
         // NOTE: in this case there should be no `subcommands` attribute on the @Command annotation.
         @Command public class Git { ... }
        
         CommandLine commandLine = new CommandLine(new Git())
                 .addSubcommand("status",   new GitStatus())
                 .addSubcommand("commit",   new GitCommit())
                 .addSubcommand("branch",   new GitBranch());
         
        Applications may be interested in the following built-in commands in picocli that can be used as subcommands:
        • CommandLine.HelpCommand - a help subcommand that prints help on the following or preceding command
        • AutoComplete.GenerateCompletion - a generate-completion subcommand that prints a Bash/ZSH completion script for its parent command, so that clients can install autocompletion in one line by running source <(parent-command generate-completion) in the shell
        Returns:
        the declaratively registered subcommands of this command, or an empty array if none
        Since:
        0.9.8
        See Also:
        CommandLine.addSubcommand(String, Object), CommandLine.HelpCommand
        Default:
        {}
      • subcommandsRepeatable

        boolean subcommandsRepeatable
        Returns whether the subcommands of this command are repeatable, that is, whether such subcommands can occur multiple times and may be followed by sibling commands instead of only by child commands of the subcommand.
        Since:
        4.2
        Default:
        false
      • addMethodSubcommands

        boolean addMethodSubcommands
        Specify whether methods annotated with @Command should be registered as subcommands of their enclosing @Command class. The default is true. For example:
         @Command
         public class Git {
             @Command
             void status() { ... }
         }
        
         CommandLine git = new CommandLine(new Git());
         
        is equivalent to this:
         // don't add command methods as subcommands automatically
         @Command(addMethodSubcommands = false)
         public class Git {
             @Command
             void status() { ... }
         }
        
         // add command methods as subcommands programmatically
         CommandLine git = new CommandLine(new Git());
         CommandLine status = new CommandLine(CommandLine.getCommandMethods(Git.class, "status").get(0));
         git.addSubcommand("status", status);
         
        Returns:
        whether methods annotated with @Command should be registered as subcommands
        Since:
        3.6.0
        See Also:
        CommandLine.addSubcommand(String, Object), CommandLine.getCommandMethods(Class, String), CommandLine.Model.CommandSpec.addMethodSubcommands()
        Default:
        true
      • separator

        String separator
        String that separates options from option parameters. Default is "=". Spaces are also accepted.
        Returns:
        the string that separates options from option parameters, used both when parsing and when generating usage help
        See Also:
        CommandLine.setSeparator(String)
        Default:
        "="
      • version

        String[] version
        Version information for this command, to print to the console when the user specifies an option to request version help. Each element of the array is rendered on a separate line.

        May contain embedded format specifiers like %n line separators. Literal percent '%' characters must be escaped with another %.

        This is not part of the usage help message.

        Returns:
        a string or an array of strings with version information about this command (each string in the array is displayed on a separate line).
        Since:
        0.9.8
        See Also:
        CommandLine.printVersionHelp(PrintStream)
        Default:
        {}
      • versionProvider

        Class<? extends CommandLine.IVersionProvider> versionProvider
        Class that can provide version information dynamically at runtime. An implementation may return version information obtained from the JAR manifest, a properties file or some other source.
        Returns:
        a Class that can provide version information dynamically at runtime
        Since:
        2.2
        Default:
        picocli.CommandLine.NoVersionProvider.class
      • mixinStandardHelpOptions

        boolean mixinStandardHelpOptions
        Adds the standard -h and --help usageHelp options and -V and --version versionHelp options to the options of this command.

        Note that if no version() or versionProvider() is specified, the --version option will not print anything.

        For internationalization: the help option has descriptionKey = "mixinStandardHelpOptions.help", and the version option has descriptionKey = "mixinStandardHelpOptions.version".

        Returns:
        whether the auto-help mixin should be added to this command
        Since:
        3.0
        Default:
        false
      • helpCommand

        boolean helpCommand
        Set this attribute to true if this subcommand is a help command, and required options and positional parameters of the parent command should not be validated. If a subcommand marked as helpCommand is specified on the command line, picocli will not validate the parent arguments (so no "missing required option" errors) and the CommandLine.printHelpIfRequested(List, PrintStream, PrintStream, Help.Ansi) method will return true.
        Returns:
        true if this subcommand is a help command and picocli should not check for missing required options and positional parameters on the parent command
        Since:
        3.0
        Default:
        false
      • synopsisHeading

        String synopsisHeading
        Set the heading preceding the synopsis text. The default heading is "Usage: " (without a line break between the heading and the synopsis text).

        May contain embedded format specifiers like %n line separators. Literal percent '%' characters must be escaped with another %.

        Returns:
        the heading preceding the synopsis text
        See Also:
        CommandLine.Help.synopsisHeading(Object...)
        Default:
        "Usage: "
      • customSynopsis

        String[] customSynopsis
        Specify one or more custom synopsis lines to display instead of an auto-generated synopsis. Each element of the array is rendered on a separate line.

        May contain embedded format specifiers like %n line separators. Literal percent '%' characters must be escaped with another %.

        Returns:
        custom synopsis text to replace the auto-generated synopsis
        See Also:
        CommandLine.Help.customSynopsis(Object...)
        Default:
        {}
      • synopsisSubcommandLabel

        String synopsisSubcommandLabel
        Specify the String to show in the synopsis for the subcommands of this command. The default is "[COMMAND]". Ignored if this command has no subcommands.
        Since:
        4.0
        Default:
        "[COMMAND]"
      • description

        String[] description
        Optional text to display between the synopsis line(s) and the list of options. Each element of the array is rendered on a separate line.

        May contain embedded format specifiers like %n line separators. Literal percent '%' characters must be escaped with another %.

        Returns:
        description of this command
        See Also:
        CommandLine.Help.description(Object...)
        Default:
        {}
      • sortOptions

        boolean sortOptions
        Specify false to show Options in declaration order in the option list of the usage help message (or to sort options by their order index if set). Note that picocli cannot reliably detect declaration order in commands that have both @Option-annotated methods and @Option-annotated fields. The default (true) is to sort alphabetically.
        Returns:
        whether options should be shown in alphabetic order.
        Default:
        true
      • sortSynopsis

        boolean sortSynopsis
        Specify false to show options in declaration order in the synopsis of the usage help message (or to sort options by their order index if set). Note that picocli cannot reliably detect declaration order in commands that have both @Option-annotated methods and @Option-annotated fields. The default (true) is to sort alphabetically.
        Returns:
        whether options in the synopsis should be shown in alphabetic order.
        Since:
        4.7.6
        Default:
        true
      • requiredOptionMarker

        char requiredOptionMarker
        Prefix required options with this character in the options list. The default is no marker: the synopsis indicates which options and parameters are required.
        Returns:
        the character to show in the options list to mark required options
        Default:
        ' '
      • defaultValueProvider

        Class<? extends CommandLine.IDefaultValueProvider> defaultValueProvider
        Class that can provide default values dynamically at runtime. An implementation may return default value obtained from a configuration file like a properties file or some other source.

        Applications may be interested in the CommandLine.PropertiesDefaultProvider built-in default provider that allows end users to maintain their own default values for options and positional parameters, which may override the defaults that are hard-coded in the application.

        Returns:
        a Class that can provide default values dynamically at runtime
        Since:
        3.6
        Default:
        picocli.CommandLine.NoDefaultProvider.class
      • showDefaultValues

        boolean showDefaultValues
        Specify true to show default values in the description column of the options list (except for boolean options). False by default.

        Note that picocli 3.2 allows embedding default values anywhere in the option or positional parameter description that ignores this setting.

        Returns:
        whether the default values for options and parameters should be shown in the description column
        Default:
        false
      • showAtFileInUsageHelp

        boolean showAtFileInUsageHelp
        Specify true to show a [@<filename>...] entry in the synopsis and parameter list of the usage help message. (The entry is not shown if expanding parameter files is disabled.)
        Since:
        4.2
        Default:
        false
      • showEndOfOptionsDelimiterInUsageHelp

        boolean showEndOfOptionsDelimiterInUsageHelp
        Specify true to show a [--] "End of options" entry in the synopsis and option list of the usage help message.
        Since:
        4.3
        Default:
        false
      • commandListHeading

        String commandListHeading
        Set the heading preceding the subcommands list. The default heading is "Commands:%n" (with a line break at the end).

        May contain embedded format specifiers like %n line separators. Literal percent '%' characters must be escaped with another %.

        Returns:
        the heading preceding the subcommands list
        See Also:
        CommandLine.Help.commandListHeading(Object...)
        Default:
        "Commands:%n"
      • footer

        String[] footer
        Optional text to display after the list of options. Each element of the array is rendered on a separate line.

        May contain embedded format specifiers like %n line separators. Literal percent '%' characters must be escaped with another %.

        Returns:
        text to display after the list of options
        See Also:
        CommandLine.Help.footer(Object...)
        Default:
        {}
      • hidden

        boolean hidden
        Set hidden=true if this command should not be included in the list of commands in the usage help of the parent command.
        Returns:
        whether this command should be excluded from the usage message
        Since:
        3.0
        Default:
        false
      • usageHelpAutoWidth

        boolean usageHelpAutoWidth
        If true, picocli will attempt to detect the terminal width and adjust the usage help message accordingly. End users may enable this by setting system property "picocli.usage.width" to AUTO, and may disable this by setting this system property to a numeric value. This feature requires Java 7 or greater. The default is false
        Since:
        4.0
        See Also:
        CommandLine.Model.UsageMessageSpec.autoWidth()
        Default:
        false
      • exitCodeOnUsageHelp

        int exitCodeOnUsageHelp
        Exit code for successful termination after printing usage help on user request. 0 by default.
        Since:
        4.0
        See Also:
        CommandLine.execute(String...)
        Default:
        0
      • exitCodeOnVersionHelp

        int exitCodeOnVersionHelp
        Exit code for successful termination after printing version help on user request. 0 by default.
        Since:
        4.0
        See Also:
        CommandLine.execute(String...)
        Default:
        0
      • exitCodeOnInvalidInput

        int exitCodeOnInvalidInput
        Exit code for command line usage error. 2 by default.
        Since:
        4.0
        See Also:
        CommandLine.execute(String...)
        Default:
        2
      • exitCodeOnExecutionException

        int exitCodeOnExecutionException
        Exit code signifying that an exception occurred when invoking the Runnable, Callable or Method user object of a command. 1 by default.
        Since:
        4.0
        See Also:
        CommandLine.execute(String...)
        Default:
        1
      • exitCodeList

        String[] exitCodeList
        Set the values to be displayed in the exit codes section as a list of "key:value" pairs: keys are exit codes, values are descriptions. Descriptions may contain "%n" line separators.

        For example:

         @Command(exitCodeListHeading = "Exit Codes:%n",
                  exitCodeList = { " 0:Successful program execution.",
                                   "64:Invalid input: an unknown option or invalid parameter was specified.",
                                   "70:Execution exception: an exception occurred while executing the business logic."})
         
        Since:
        4.0
        Default:
        {}
      • scope

        CommandLine.ScopeType scope
        Returns whether subcommands inherit their attributes from this parent command.
        Since:
        4.6
        Default:
        picocli.CommandLine.ScopeType.LOCAL
      • modelTransformer

        Class<? extends CommandLine.IModelTransformer> modelTransformer
        Returns the model transformer for this command.
        Since:
        4.6
        Default:
        picocli.CommandLine.NoOpModelTransformer.class