CODEWITHSUNDEEP
javaclassobjectinstanceinner-classes
nikagar4
nikagar4

Reputation: 840

Two classes making same instance?? java

so i had this exam in university which was to create book class which would have author, title, content and translator.

main requirement was to create only 1 class and create inner classes within it (author and translator)

and one Main class to test it.

Problem was that when i created author and translator objects and tried to change their names, both of them would change names.

Here's my code:

Book Class:

public class Book {
    private Author author;
    private Translator translator;
    private String title;
    private String text;

    public interface IPerson {
        public void setFirstName(String name);
        public String getFirstName();
        public void setLastName(String name);
        public String getLastName();
    }
    //Author
    public class Author implements IPerson{
        private String firstName;
        private String lastName;

        public Author(String f, String l){
            firstName = f;
            lastName = l;
            author = this;
        }

        public void setFirstName(String name){
            this.firstName = name;
        }

        public String getFirstName(){
            return this.firstName;
        }

        public void setLastName(String name){
            this.lastName = name;
        }

        public String getLastName(){
            return this.lastName;
        }

    }
    public Author getAuthor(){
        return this.author;
    }
    //Translator
    public class Translator extends Author{

        public Translator(String f, String l) {
            super(f, l);
            translator = this;
        }
    }
    public Translator getTranslator(){
        return this.translator;
    }
    public String getTranslatorFullName(){
        return this.getTranslator().getFirstName() + " " + this.getTranslator().getLastName();
    }
    public String getText() {
        return this.text;
    }

    public void setText(String text) {
        this.text = text;
    }

    public String getTitle() {
        return this.title;
    }

    public void setTitle(String title) {
        this.title = title;
    }
    public String getDisplayTitle(){
        return getTitle() + " Author: " + this.getAuthor().getFirstName() + " " + this.getAuthor().getLastName();
    }
}

Main Class:

public class Main {
public static void main(String[] args){
    Book mybook = new Book();
    mybook.setTitle("Fight Club");
    mybook.setText("First rule of Fight Club, you do not talk about Fight Club");
    Book.Author author = mybook.new Author("John","Doe");
    Book.Translator translator = mybook.new Translator("Alan","Rickman");
    System.out.println(mybook.getDisplayTitle());
    System.out.println(mybook.getAuthor().getLastName());
    System.out.println(mybook.getAuthor().getFirstName());
    System.out.println(mybook.getTranslatorFullName());
    System.out.println(mybook.getTranslator().getFirstName());
}
}

It Had to pass these tests, what was my problem?

Don't tell me to make Translator implement IPerson, it was my teachers request to extend

Upvotes: 0

Views: 88

Answers (3)

brso05
brso05

Reputation: 13222

You can fix it like this:

public Author(String f, String l, boolean authorCheck){
    firstName = f;
    lastName = l;
    if(authorCheck)
    {
        author = this;
    }
}

public Author(String f, String l){
    firstName = f;
    lastName = l;
    author = this;
}

public Translator(String f, String l) {
    super(f, l, false);
    translator = this;
}

Upvotes: 1

Orejano
Orejano

Reputation: 1824

It would make more sense if Translator implements IPerson instead of extending Author.

Upvotes: 1

discipliuned
discipliuned

Reputation: 936

You're making a super(f,l) call in the constructor of Translator. Translator is changing the Author fields as the superclass of Translator is Author.

Upvotes: 0

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