Command

/**
* 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 strings: a command word and a second
* word (for example, if the command was "take map", then the two strings
* obviously 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 command word is <null>.
*
* If the command had only one word, then the second word is <null>.
*
* @author Ahmad Lamaul Farid
* @version 12 November 2020
*/

public class Command
{
    private String commandWord;
    private String secondWord;

    /**
    * Create a command object. First and second word must be supplied, but
    * either one (or both) can be null.
    * @param firstWord The first word of the command. Null if the command
    * was not recognised.
    * @param secondWord The second word of the command.
    */
    public Command(String firstWord, String secondWord)
    {
        commandWord = firstWord;
        this.secondWord = secondWord;
    }

    /**
    * Return the command word (the first word) of this command. If the
    * command was not understood, the result is null.
    * @return The command word.
    */
    public String 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 == null);
    }

    /**
    * @return true if the command has a second word.
    */
    public boolean hasSecondWord()
    {
        return (secondWord != null);
    }
}