import java.util.Scanner;
/**
* This class is part of the "World of Zuul" application.
* "World of Zuul" is a very simple, text based adventure game.
*
* This class holds information about a command that was issued by the user.
* A command currently consists of two parts: a CommandWord and a string
* (for example, if the command was "take map", then the two parts
* are TAKE and "map").
*
* The way this is used is: Commands are already checked for being valid
* command words. If the user entered an invalid command (a word that is not
* known) then the CommandWord is UNKNOWN.
*
* If the command had only one word, then the second word is <null>.
*
* ---------------------------------------------------------------------------
* The getCommand method that was in Parser was moved to this class since
* I really don't see a need for a whole class to do this.
* The method was modified so that it takes a String as an argument.
* This allows us to be able to parse commands no matter where they come from.
* Notice that this method is static because we use it to create an object
* of this type. We have seen this before--e.g. the Matrix class in the
* RayTracer project. These are common
* ---------------------------------------------------------------------------
*
* @author Michael Kolling and David J. Barnes
* @version 2006.03.30
*
* @author Modified by Charles Cusack October, 2008
*
*/
public class Command
{
private CommandWord commandWord;
private String secondWord;
/**
* Create a command object. First and second words must be supplied, but
* the second may be null.
* @param commandWord The CommandWord. UNKNOWN if the command word
* was not recognised.
* @param secondWord The second word of the command. May be null.
*/
public Command(CommandWord commandWord, String secondWord)
{
this.commandWord = commandWord;
this.secondWord = secondWord;
}
/**
* Return the command word (the first word) of this command.
* @return The command word.
*/
public CommandWord getCommandWord()
{
return commandWord;
}
/**
* @return The second word of this command. Returns null if there was no
* second word.
*/
public String getSecondWord()
{
return secondWord;
}
/**
* @return true if this command was not understood.
*/
public boolean isUnknown()
{
return (commandWord == CommandWord.UNKNOWN);
}
/**
* @return true if the command has a second word.
*/
public boolean hasSecondWord()
{
return (secondWord != null);
}
public static Command getCommand(String input)
{
String word1 = null;
String word2 = null;
// Find up to two words on the line.
Scanner tokenizer = new Scanner(input);
if(tokenizer.hasNext()) {
word1 = tokenizer.next(); // get first word
if(tokenizer.hasNext()) {
word2 = tokenizer.next(); // get second word
// note: we just ignore the rest of the input line.
}
}
return new Command(CommandWord.getCommandWord(word1), word2);
}
}