How can i add this .equals() method

Question

public class TestLibraryBook {

    public static void main(String[] args) {
        LibraryBook book1, book2;
        book2 = new LibraryBook("Ali's book", "Ali", "1st June", 250);
        book1 = book2;
        LibraryBook book5, book6;
        LibraryBook book3, book4;
        LibraryBook book7, book8, book9, book10;
        book4 = new LibraryBook("David's Labs", "David", "29 of February", 1);
        book3 = book4;
        book6 = new LibraryBook("James adventure", "James", "May", 25);
        book5 = book6;

        book7 = new LibraryBook("James holiday", "Jane", "Jun", 31);
        book8 = book7;
        book9 = new LibraryBook("James holiday", "Jane", "April", 53);
        book10 = book9;
    }
}

And this is my second class

public class LibraryBook {
    // variables
    public String title;
    public String author;
    public String dueDate;
    public int timesLoaned;

    // constructor
    public LibraryBook(String title, String author, String dueDate, int timesLoaned) {
        this.title = title;
        this.author = author;
        this.dueDate = dueDate;
        this.timesLoaned = timesLoaned;

    }
    // constructor

    public LibraryBook() {
        title = "no info";
        author = "no info";
        dueDate = " no info ";
        timesLoaned = 0;
    }

    public boolean equals() {
        if (title.equals(title) & author.equals(author)) {
            return true;
        }
        return false;
    }
}

I have two classes with objects and references I'm trying to say if their title and author are same they are same. So I want to add boolean equals method in my LibraryBook class so that books with the same title and author should be considered the same irrespective of their dueDate or timesLoaned. I could not do that pls help me.

Does this answer your question? [How to override equals method in Java](https://stackoverflow.com/questions/8180430/how-to-override-equals-method-in-java) — locus2k, Dec 04 '19 at 20:32

score 0 · Answer 1 · edited Dec 04 '19 at 21:44

If you are no Netbeans just right click your class, then generate code, equals & hash code and only select title and Netbeans will auto-generate the method for you. And the problem with your method is that you are comparing the object with itself, you need to receive another LibraryBook as a parameter and compare the 2.

    public boolean equals(LibraryBook other)
{
    if(this.title.equals(other.title) && this.author.equals(other.author))
    {
        return true;
    }
    return false;

    }
}

How can i add this .equals() method

1 Answers1