Package org.jline.shell.impl

Class DefaultCommandDispatcher

java.lang.Object

org.jline.shell.impl.DefaultCommandDispatcher

All Implemented Interfaces:

AutoCloseable, CommandDispatcher

public class DefaultCommandDispatcher
extends Object
implements CommandDispatcher

Default implementation of CommandDispatcher that supports pipeline execution.

This dispatcher parses command lines using PipelineParser, resolves commands from registered CommandGroups, and executes pipeline stages with proper pipe/redirect/conditional handling.

When a JobManager is configured, the dispatcher supports:

• Background execution via trailing &
• Foreground job tracking
• Built-in jobs, fg, bg commands

When an AliasManager is configured, the dispatcher expands aliases before pipeline parsing and automatically registers alias/unalias commands.

Since:

4.0

See Also:

• CommandDispatcher
• PipelineParser

Constructor Summary

Constructors

Constructor	Description
DefaultCommandDispatcher(LineReader reader)	Creates a new dispatcher for the given reader.
DefaultCommandDispatcher(Terminal terminal)	Creates a new dispatcher for the given terminal.
DefaultCommandDispatcher(Terminal terminal, JobManager jobManager)	Creates a new dispatcher for the given terminal with optional job management.
DefaultCommandDispatcher(Terminal terminal, JobManager jobManager, PipelineParser pipelineParser, AliasManager aliasManager)	Creates a new dispatcher with all configuration options.
DefaultCommandDispatcher(Terminal terminal, JobManager jobManager, PipelineParser pipelineParser, AliasManager aliasManager, LineExpander lineExpander, ScriptRunner scriptRunner)	Creates a new dispatcher with all configuration options including line expansion and script execution.
DefaultCommandDispatcher(Terminal terminal, JobManager jobManager, PipelineParser pipelineParser, AliasManager aliasManager, LineExpander lineExpander, ScriptRunner scriptRunner, Parser parser)	Creates a new dispatcher with all configuration options including line expansion, script execution and parser.

Method Summary

Modifier and Type	Method	Description
void	addGroup(CommandGroup group)	Adds a command group to this dispatcher.
void	close()	No-op default implementation; does nothing.
Completer	completer()	Creates a completer that provides completions for every registered command name and its aliases.
CommandDescription	describe(CommandLine commandLine)	Returns a description for the command at the current command line position.
Object	execute(String line)	Executes a command line string.
Object	execute(Pipeline pipeline)	Executes a pre-parsed pipeline.
List<CommandGroup>	groups()	Returns all registered command groups.
void	initialize(File script)	Initializes the dispatcher, optionally executing a startup script.
void	interruptCurrentCommand()	Interrupts the currently executing command, if any.
CommandSession	session()	Returns the command session used by this dispatcher.
Terminal	terminal()	Returns the terminal associated with this dispatcher.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.jline.shell.CommandDispatcher

cleanUp, errorStyle, findCommand, trace

Constructor Details

DefaultCommandDispatcher

public DefaultCommandDispatcher(Terminal terminal)

Creates a new dispatcher for the given terminal.

Parameters:

terminal - the terminal

DefaultCommandDispatcher

public DefaultCommandDispatcher(LineReader reader)

Creates a new dispatcher for the given reader.

Parameters:

reader - the reader

DefaultCommandDispatcher

public DefaultCommandDispatcher(Terminal terminal,
 JobManager jobManager)

Creates a new dispatcher for the given terminal with optional job management.

Parameters:

terminal - the terminal

jobManager - the job manager, or null for no job control

DefaultCommandDispatcher

public DefaultCommandDispatcher(Terminal terminal,
 JobManager jobManager,
 PipelineParser pipelineParser,
 AliasManager aliasManager)

Creates a new dispatcher with all configuration options.

When a non-null JobManager is provided, the dispatcher automatically registers JobCommands and supports background execution via trailing &.

When a non-null AliasManager is provided, the dispatcher expands aliases before pipeline parsing and automatically registers AliasCommands.

When a non-null PipelineParser is provided, it is used instead of the default parser. This allows custom operator registration and subclass overrides.

Parameters:

terminal - the terminal

jobManager - the job manager, or null for no job control

pipelineParser - the pipeline parser, or null for the default parser

aliasManager - the alias manager, or null for no alias support

DefaultCommandDispatcher

public DefaultCommandDispatcher(Terminal terminal,
 JobManager jobManager,
 PipelineParser pipelineParser,
 AliasManager aliasManager,
 LineExpander lineExpander,
 ScriptRunner scriptRunner)

Creates a new dispatcher with all configuration options including line expansion and script execution.

Parameters:

terminal - the terminal

jobManager - the job manager, or null for no job control

pipelineParser - the pipeline parser, or null for the default parser

aliasManager - the alias manager, or null for no alias support

lineExpander - the line expander, or null for no variable expansion

scriptRunner - the script runner, or null for no script support

DefaultCommandDispatcher

public DefaultCommandDispatcher(Terminal terminal,
 JobManager jobManager,
 PipelineParser pipelineParser,
 AliasManager aliasManager,
 LineExpander lineExpander,
 ScriptRunner scriptRunner,
 Parser parser)

Creates a new dispatcher with all configuration options including line expansion, script execution and parser.

Parameters:

terminal - the terminal

jobManager - the job manager, or null for no job control

pipelineParser - the pipeline parser, or null for the default parser

aliasManager - the alias manager, or null for no alias support

lineExpander - the line expander, or null for no variable expansion

scriptRunner - the script runner, or null for no script support

parser - the argument parser, or null for the default parser

Method Details

addGroup

public void addGroup(CommandGroup group)

Description copied from interface: CommandDispatcher

Adds a command group to this dispatcher.

Specified by:

addGroup in interface CommandDispatcher

Parameters:

group - the command group to add

groups

public List<CommandGroup> groups()

Description copied from interface: CommandDispatcher

Returns all registered command groups.

Specified by:

groups in interface CommandDispatcher

Returns:

the list of command groups

execute

public Object execute(String line)
               throws Exception

Description copied from interface: CommandDispatcher

Executes a command line string.

The dispatcher parses the line (potentially into a pipeline) and executes the commands.

Specified by:

execute in interface CommandDispatcher

Parameters:

line - the command line to execute

Returns:

the result of execution

Throws:

Exception - if execution fails

execute

public Object execute(Pipeline pipeline)
               throws Exception

Description copied from interface: CommandDispatcher

Executes a pre-parsed pipeline.

Specified by:

execute in interface CommandDispatcher

Parameters:

pipeline - the pipeline to execute

Returns:

the result of execution

Throws:

Exception - if execution fails

completer

public Completer completer()

Creates a completer that provides completions for every registered command name and its aliases. Builds a SystemCompleter, registers a completer for each command and each of its alias strings, and finalizes it into a candidate-producing completer.

Specified by:

completer in interface CommandDispatcher

Returns:

a Completer that offers argument and command-name completions for all registered commands and aliases

describe

public CommandDescription describe(CommandLine commandLine)

Description copied from interface: CommandDispatcher

Returns a description for the command at the current command line position.

Used by widgets for context-sensitive help.

Specified by:

describe in interface CommandDispatcher

Parameters:

commandLine - the parsed command line

Returns:

the command description, or null

terminal

public Terminal terminal()

Description copied from interface: CommandDispatcher

Returns the terminal associated with this dispatcher.

Specified by:

terminal in interface CommandDispatcher

Returns:

the terminal

session

public CommandSession session()

Returns the command session used by this dispatcher.

Returns:

the command session

interruptCurrentCommand

public void interruptCurrentCommand()

Interrupts the currently executing command, if any.

This is typically called from a signal handler (e.g., SIGINT) to interrupt the foreground command without killing the shell.

initialize

public void initialize(File script)
                throws Exception

Description copied from interface: CommandDispatcher

Initializes the dispatcher, optionally executing a startup script.

Specified by:

initialize in interface CommandDispatcher

Parameters:

script - the initialization script, or null

Throws:

Exception - if initialization fails

close

public void close()

No-op default implementation; does nothing. Subclasses may override to release or close allocated resources.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface CommandDispatcher