Package org.jline.shell

Interface CommandDispatcher

All Superinterfaces:

AutoCloseable

All Known Implementing Classes:

DefaultCommandDispatcher

public interface CommandDispatcher
extends AutoCloseable

Central dispatcher that aggregates CommandGroups and handles command resolution, execution, and completion.

CommandDispatcher separates the aggregation and dispatch role from individual command semantics defined in Command and CommandGroup.

Example:

 CommandDispatcher dispatcher = new DefaultCommandDispatcher(terminal);
 dispatcher.addGroup(myGroup);
 Object result = dispatcher.execute("echo hello | grep h");
 

Since:

4.0

See Also:

• CommandGroup
• Command
• DefaultCommandDispatcher

Method Summary

Modifier and Type	Method	Description
void	addGroup(CommandGroup group)	Adds a command group to this dispatcher.
default void	cleanUp()	Performs cleanup between command executions (e.g., resetting state).
void	close()	Closes this dispatcher and releases resources.
Completer	completer()	Returns a completer that provides tab completion across all registered commands.
CommandDescription	describe(CommandLine commandLine)	Returns a description for the command at the current command line position.
default AttributedStyle	errorStyle()
Object	execute(String line)	Executes a command line string.
Object	execute(Pipeline pipeline)	Executes a pre-parsed pipeline.
default Command	findCommand(String name)	Finds a command by name or alias across all registered groups.
List<CommandGroup>	groups()	Returns all registered command groups.
default void	initialize(File script)	Initializes the dispatcher, optionally executing a startup script.
Terminal	terminal()	Returns the terminal associated with this dispatcher.
default void	trace(Throwable exception)	Traces an exception (e.g., prints it to the terminal).

Method Details

addGroup

void addGroup(CommandGroup group)

Adds a command group to this dispatcher.

Parameters:

group - the command group to add

groups

List<CommandGroup> groups()

Returns all registered command groups.

Returns:

the list of command groups

findCommand

default Command findCommand(String name)

Finds a command by name or alias across all registered groups.

Parameters:

name - the command name or alias

Returns:

the command, or null if not found

execute

Object execute(String line)
        throws Exception

Executes a command line string.

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

Parameters:

line - the command line to execute

Returns:

the result of execution

Throws:

Exception - if execution fails

execute

Object execute(Pipeline pipeline)
        throws Exception

Executes a pre-parsed pipeline.

Parameters:

pipeline - the pipeline to execute

Returns:

the result of execution

Throws:

Exception - if execution fails

completer

Completer completer()

Returns a completer that provides tab completion across all registered commands.

Returns:

the aggregated completer

describe

CommandDescription describe(CommandLine commandLine)

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

Used by widgets for context-sensitive help.

Parameters:

commandLine - the parsed command line

Returns:

the command description, or null

terminal

Terminal terminal()

Returns the terminal associated with this dispatcher.

Returns:

the terminal

initialize

default void initialize(File script)
                 throws Exception

Initializes the dispatcher, optionally executing a startup script.

Parameters:

script - the initialization script, or null

Throws:

Exception - if initialization fails

cleanUp

default void cleanUp()

Performs cleanup between command executions (e.g., resetting state).

errorStyle

default AttributedStyle errorStyle()

Returns:

A AttributedStyle to be used when printing exception messages.

trace

default void trace(Throwable exception)

Traces an exception (e.g., prints it to the terminal).

Parameters:

exception - the exception to trace

close

void close()

Closes this dispatcher and releases resources.

Specified by:

close in interface AutoCloseable