org.limitless.nmc.Prototype1
Class CommandProcessor

java.lang.Object
  org.limitless.nmc.Prototype1.CommandProcessor

public class CommandProcessor
extends java.lang.Object

This provides the command dispatcher. It doesn't actually parse commands, but rather, it maps keywords to command objects that will do the job. To add a command, put a map entry in this class's constructor.

Version:

1.0

Author:

Brian Jones

Nested Class Summary

static class

CommandProcessor.UnknownCommandException A command was given that isn't defined.

Field Summary

Command	Command
private java.util.Map	commandMap This holds (String,Command).
private CommandParser	commandParser The command-parser worker (stateless object).
private static CommandProcessor	instance Singleton instance variable.
private static org.apache.log4j.Logger	logger
private boolean	shutdownRequested This goes to true when a shutdown/exit request is given.

Constructor Summary

private

CommandProcessor() This populates the map of commands to command-objects.

Method Summary

Command	fetchCommand(java.lang.String command) This is used to gain access to the command that would be dispatched.
(package private) java.util.Collection	fetchDefinedCommands()
static CommandProcessor	Instance() Fetch the object to do the work.
void	invoke(java.lang.String rawInput) This is given an input command and causes it to be called.
boolean	isShutdownRequested() This returns true if a shutdown request was made.
(package private) void	requestShutdown()

Methods inherited from class java.lang.Object

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

Field Detail

logger

private static org.apache.log4j.Logger logger

commandParser

private CommandParser commandParser

The command-parser worker (stateless object).

commandMap

private java.util.Map commandMap

This holds (String,Command).

instance

private static CommandProcessor instance

Singleton instance variable.

shutdownRequested

private boolean shutdownRequested

This goes to true when a shutdown/exit request is given.

Command

public Command Command

Constructor Detail

CommandProcessor

private CommandProcessor()

This populates the map of commands to command-objects.

Method Detail

requestShutdown

void requestShutdown()

isShutdownRequested

public boolean isShutdownRequested()

This returns true if a shutdown request was made.

Returns:

true if shutdown is requested

Instance

public static CommandProcessor Instance()

Fetch the object to do the work.

Returns:

The one and only one object.

fetchCommand

public Command fetchCommand(java.lang.String command)
                     throws CommandProcessor.UnknownCommandException

This is used to gain access to the command that would be dispatched. This is an excellent way to fetch an object to get its help text for instance. This is legal for use to bypass the built-in dispatcher, but it would require a lot more work to use.

Parameters:

command - Raw string of a single command line

Returns:

A Command object.

Throws:

CommandProcessor.UnknownCommandException

invoke

public void invoke(java.lang.String rawInput)
            throws CommandProcessor.UnknownCommandException

This is given an input command and causes it to be called. This can be given a command from any source.

Parameters:

rawInput - String for the command.

Throws:

CommandProcessor.UnknownCommandException

fetchDefinedCommands

java.util.Collection fetchDefinedCommands()