Why getter method doesn't return any object's attribute?

Question

My program should return the different attributes for two different objects. In my main method I set those attributes as the arguments while creating new objects. But when I call those getter methods (which I have written in a separate class, I can post that class if needed), it doesn't return all the attributes. It only prints out the first attributes (which is also set as first argument), not the other two values. I don't know where I have done wrong.

my code: Main class:

    package main;

public class Main {

    public static void main(String[] args) {

        //creating object for book 1 
        Book book1 = new Book("The brief history of time", "111", new String[]{"S. hawking", "hawking's friends"});
        //creating object for book 2
        Book book2 = new Book("100 years of solitude", "222", new String[]{"G.marquez", "marquez's friend"});

        System.out.println("All info for the first book: \n");

        System.out.println("Name: " + book1.getName());
        System.out.println("ISBN: " + book1.getIsbn());
        System.out.println("Authors: " + book1.getAuthors());

        System.out.println("\n\n");
        System.out.println("All info for the second book: \n");
        System.out.println("Name: " + book2.getName());
        System.out.println("ISBN: " + book2.getIsbn());
        System.out.println("Authors: " + book2.getAuthors());

    }

}

Book class:

    package main;

public class Book {
    //variables

    private String name;
    private String isbn;
    private String[] authors;

    //constructors
    public Book(String name, String isbn, String[] authors) {
        this.name = name;
        this.isbn = name;
        this.authors = authors;

    }

    //setters
    public void setName(String name) {
        this.name = name;
    }

    public void setIsbn(String isbn) {
        this.isbn = isbn;
    }

    public void setAuthors(String[] authors) {
        this.authors = authors;
    }

    //getters
    public String getName() {
        return name;
    }

    public String getIsbn() {
        return isbn;
    }

    public String[] getAuthors() {
        return authors;
    }

}

Can you post the book class, the actual output you get and the output you are expecting? — Paolo, Jan 09 '15 at 15:20
You need to post the output you are getting vs. what you expect. The internet doesn't have a crystal ball! — Paolo, Jan 09 '15 at 15:24
this.isbn = name; - Really? And use java.util.Arrays.toString(book1.getAuthors()) if you want pretty pring arrays — vrudkovsk, Jan 09 '15 at 15:26
@Paolo the code is there. It's easier for us to spot the problems. — Luiggi Mendoza, Jan 09 '15 at 15:27
vrudkovsk, hahahah, just let me laugh, really I am laughing knowing that what mistake I have done. gonna fix it, hope it will work soon. — Riyana, Jan 09 '15 at 15:28
@someone You could set up your IDE to warn you about unused variables. That way you may had noticed, that the constructor argument `isbn` is never used anywhere. — Tom, Jan 09 '15 at 15:30
Well, I don't know which IDE you're using, but you might find information about that setting in the manual of your IDE at the topic `inspections` (or something like this). — Tom, Jan 09 '15 at 15:40

score 1 · Accepted Answer · answered Jan 09 '15 at 15:26

You need to iterate the authors array in order to print the Strings inside it. something like this:

    System.out.println("All info for the first book: \n");

    System.out.println("Name: " + book1.getName());
    System.out.println("ISBN: " + book1.getIsbn());
    for (String author : book1.getAuthors()) {
        System.out.println("Author: " + author);
    }

Also there's a problem in your Book class constructor:

public Book(String name, String isbn, String[] authors) {
    this.name = name;
    this.isbn = name; // this.isbn is not name!
    this.authors = authors;
}

must be:

public Book(String name, String isbn, String[] authors) {
    this.name = name;
    this.isbn = isbn;
    this.authors = authors;
}

Or use `Arrays.toString(book1.getAuthors()`. – Luiggi Mendoza Jan 09 '15 at 15:26 — Luiggi Mendoza, Jan 09 '15 at 15:26

score 0 · Answer 2 · answered Jan 09 '15 at 15:28

0

When you want to print a string array you can use this .

System.out.println(Arrays.toString(book1.getAuthors()));

answered Jan 09 '15 at 15:28

uhs

838
1
7
21

score 0 · Answer 3 · edited May 23 '17 at 10:33

0

There is a problem with Book constructor:

public Book(String name, String isbn, String[] authors) {
    this.name = name;
    this.isbn = name; // you are setting isbn as name! 
    this.authors = authors;   
}

I think you need to define how getAuthors prints the authors array, like What's the simplest way to print a Java array?

edited May 23 '17 at 10:33

Community

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answered Jan 09 '15 at 15:32

Clau St

970
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Why getter method doesn't return any object's attribute?

3 Answers3