What is an object in Java?

Class — is a template or description of how objects will look. Object — is an instance of a class. An object has:

• State: Represented as fields (instance variables) of the object. These are the data stored by the object.
• Behavior: Represented as methods. These are actions that the object can perform or that can be performed on the object.
• Identity: A unique name that distinguishes one object from another. For reference types in Java, the identifier is a reference.

Example:

class Dog {
    // State (fields)
    String name;
    int age;

    // Constructor (creating an object)
    public Dog(String name, int age) {
        this.name = name;
        this.age = age;
    }

    // Behavior (methods)
    public void bark() {
        System.out.println(name + " barks!");
    }

    public void growOlder() {
        this.age++;
        System.out.println(name + " is now " + age + " years old.");
    }

    public static void main(String[] args) {
        // Creating Dog objects
        Dog myDog = new Dog("Bobic", 3); // myDog object
        Dog hisDog = new Dog("Sharik", 5); // hisDog object

        // Accessing object state
        System.out.println("My dog's name: " + myDog.name);
        System.out.println("His dog's age: " + hisDog.age);

        // Calling object behavior
        myDog.bark();
        hisDog.growOlder();
    }
}