toString() in Java

Java toString() metodi

Ixtiyoriy ob’yektni string(satr) ko’rinishida ifodalash uchun doimo toString() metodidan foydalanamiz

toString() metodi ob’yektning satr ko’rinishini qaytaradi. Ixtiyoriy ob’yektni chop qilganimizda Java kompilyatori ob’ekt ichidagi toString() metodini ishlatadi. Agar toString() metodi overrid qilinmagan bo’lsa obektning byte ko’rinishi chop qilinadi. toString() metodini overrid qilish orqali ob’ekt haqidagi kerakli ma’lumotlarni qaytarishimiz mumkin.

Misollar:

#1. toString() metodini overrid qilmasdan ob’ektni chop qilish

Book.java:

/**
 * Created by Mansurjon on 3/1/2017.
 */
public class Book {
    private int id;
    private String name;
    private String author;
    private float price;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public float getPrice() {
        return price;
    }

    public void setPrice(float price) {
        this.price = price;
    }

    public Book(int id, String name, String author, float price) {
        this.id = id;
        this.name = name;
        this.author = author;
        this.price = price;
    }
}

BookMain.java

package tostring;

/**
 * Created by Mansurjon on 3/1/2017.
 */
public class BookMain {
    public static void main(String[] args) {
        Book book = new Book(1,"Философия Java", "B.Ekkel", 82);
        System.out.println(book);

    }

}

Natija:

Book@1c63996

#2. toString() metodini overrid qilish

Book.java:

package tostring;

/**
 * Created by Mansurjon on 3/1/2017.
 */
public class Book {
    private int id;
    private String name;
    private String author;
    private float price;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

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

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public float getPrice() {
        return price;
    }

    public void setPrice(float price) {
        this.price = price;
    }

    public Book(int id, String name, String author, float price) {
        this.id = id;
        this.name = name;
        this.author = author;
        this.price = price;
    }

    @Override
    public String toString() {
        return "Kitob haqida ma'lumotlar: {" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", author='" + author + '\'' +
                ", price=" + price +
                '}';
    }
}

BookMain.java

BookMain.java

package tostring;

/**
 * Created by Mansurjon on 3/1/2017.
 */
public class BookMain {
    public static void main(String[] args) {
        Book book = new Book(1,"Философия Java", "B.Ekkel", 82);
        System.out.println(book);

    }

}

Natija:

Kitob haqida ma'lumotlar: {id=1, name='Философия Java', author='B.Ekkel', price=82.0}