Getter/setter methods -- how do I use the return values

Question

I'm just learning Java, and I haven't been to this site since the end of July, I think. I have a question regarding getter and setter methods. I switched to the book Head First Java after a poster here recommended it. I'm only about a hundred pages into the book, so the code I'm submitting here reflects that. It's the beginnings of a program I'd eventually like to complete that will take the entered information of my CD's and alphabetize them according to whatever criteria I (or any user for that matter) choose. I realize that this is just the very beginning, and I don't expect to have the complete program completed any time soon -- it's my long term goal, but I thought I could take what I'm learning in the book and put it to practical use as I go along (or at lest try to).
Yes I could have this already done it Excel, but where's the fun and challenge in that? :) Here's the code:
// This program allows the user to enter CD information - Artist name, album title, and year of release -- and then organizes it according the the user's choice according to the user's criteria -- either by artist name, then title, then year of release, or by any other order according to the user's choice.
//First, the class CDList is created, along with the necessary variables.
class CDList{
     private String artistName;//only one string for the artist name -- including spaces.
     private String albumTitle;//only one string the title name -- including spaces.
     private int yearOfRelease;
     private String recordLabel;
     public void setArtistName(String artist){
     artistName = artist;
     public void setAlbumTitle(String album){
     albumTitle = album;
     public void setYearOfRelease(int yor){
     yearOfRelease = yor;
     public void setLabel(String label){
     recordLabel = label;
     public String getArtistName(){
     return artistName;
     public String getAlbumTitle(){
     return albumTitle;
     public int getYearOfRelease(){
     return yearOfRelease;
    public String getLabel(){
    return recordLabel;
void printout () {
       System.out.println ("Artist Name: " + getArtistName());
       System.out.println ("Album Title: " + getAlbumTitle());
       System.out.println ("Year of Release: " + getYearOfRelease());
       System.out.println ("Record Label: " + getLabel());
       System.out.println ();
import static java.lang.System.out;
import java.util.Scanner;
class CDListTestDrive {
     public static void main( String[] args ) {
          Scanner s=new Scanner(System.in);
          CDList[] Record = new CDList[4];
          int x=0;     
          while (x<4) {
          Record[x]=new CDList();
          out.println ("Artist Name: ");
          String artist = s.nextLine();
          Record[x].setArtistName(artist);
          out.println ("Album Title: ");
          String album = s.nextLine();
          Record[x].setAlbumTitle(album);
          out.println ("Year of Release: ");
          int yor= s.nextInt();
                s.nextLine();
          Record[x].setYearOfRelease(yor);
          out.println ("Record Label: ");
          String label = s.nextLine();
          Record[x].setLabel(label);
          System.out.println();
          x=x+1;//moves to next CDList object;
          x=0;
          while (x<4) {
          Record[x].getArtistName();
          Record[x].getAlbumTitle();
          Record[x].getYearOfRelease();
          Record[x].getLabel();
          Record[x].printout();
          x=x+1;
               out.println("Enter a Record Number: ");
               x=s.nextInt();
               x=x-1;
               Record[x].getArtistName();
            Record[x].getAlbumTitle();
            Record[x].getYearOfRelease();
            Record[x].getLabel();
            Record[x].printout();
     }//end main
}//end class          First, I'd like to ask anyone out there to see if I could have written this any more efficiently, with the understanding that I'm only one hundred pages into the book, and I've only gotten as far as getter and setter methods, instance variables, objects and methods. The scanner feature I got from another book, but I abandoned it in favor of HFJ.
Secondly --
I'm confused about getter and setter methods -- I'd like someone to explain to me what they are used for exactly and the difference between the two. I have a general idea, that getters get a result from the method and setters set or maybe assign a value to variable. I submitted this code on another site, and one of the responders told me I wasn't using the returned values from the getter methods (he also told me about using a constructor method, but I haven't got that far in the book yet.). The program compiles and runs fine, but I can't seem to figure out how I'm not using the returned values from the getter methods. Please help and if you can explain in 'beginners terms,' with any code examples you think are appropriate. It will be greatly appreciated.
By the way, I'm not a professional programmer -- I'm learning Java because of the intellectual exercise and the fun of it. So please keep that in mind as well.
Edited by: Straitsfan on Sep 29, 2009 2:03 PM

Answer 1

Straitsfan wrote:
First, I'd like to ask anyone out there to see if I could have written this any more efficiently, with the understanding that I'm only one hundred pages into the book, and I've only gotten as far as getter and setter methods, instance variables, objects and methods. The scanner feature I got from another book, but I abandoned it in favor of HFJ.Yes, there is tons you could have done more efficiently. But this is something every new programmer goes through, and I will not spoil the fun. You see, in 3 to 6 months when you have learned much more Java, assuming you stick with it, you will look back at this and be like "what the hell was I thinking" and then realize just haw far you have come. So enjoy that moment and don't spoil it now by asking for what could have been better/ more efficient. If it works it works, just be happy it works.
Straitsfan wrote:
Secondly --
I'm confused about getter and setter methods -- I'd like someone to explain to me what they are used for exactly and the difference between the two. I have a general idea, that getters get a result from the method and setters set or maybe assign a value to variable. I submitted this code on another site, and one of the responders told me I wasn't using the returned values from the getter methods (he also told me about using a constructor method, but I haven't got that far in the book yet.). The program compiles and runs fine, but I can't seem to figure out how I'm not using the returned values from the getter methods. Please help and if you can explain in 'beginners terms,' with any code examples you think are appropriate. It will be greatly appreciated.
By the way, I'm not a professional programmer -- I'm learning Java because of the intellectual exercise and the fun of it. So please keep that in mind as well.First, if you posted this somewhere else you should link to that post, it is good you at least said you did, but doubleposting is considered very rude because what inevitably happens in many cases is the responses are weighed against each other. So you are basically setting anyone up who responds to the post for a trap that could make them look bad when you double post.
You are setting you getters and setters up right as far as I can tell. Which tells me that I think you grasp that a getter lets another class get the variables data, and a setter lets another class set the data. One thing, be sure to use the full variable name so you should have setRecordLabel() and getRecodLabel() as opposed to setLabel() and getLabel(). Think about what happens if you go back and add a label field to the CDList class, bad things the way you have it currently. Sometimes shortcuts are not your friend.
And yes, you are using the getters all wrong since you are not saving off what they return, frankly I am suprised it compiles. It works because you don't really need to use the getters where you have them since the CDList Record (should be lowercase R by the way) object already knows the data and uses it in the printout() method. Basically what you are doing in lines like:
Record[x].getArtistName();is asking for the ArtistName in Record[x] and then getting the name and just dropping it on the floor. You need to store it in something if you want to keep it, like:
String artistName = Record[x].getArtistName();See how that works?
Hope this helped, keep up the good learning and good luck.
JSG