How does object instantiation occur in Java?

Object instantiation in Java occurs when the 'new' keyword is used to create an instance of a class.

In Java, object instantiation is the process of creating an instance of a class. This is done using the 'new' keyword followed by a call to the class constructor. The constructor is a special method in the class that is used to initialise the new object. The 'new' keyword allocates memory for the new object and returns a reference to that memory. This reference is then stored in a variable.

For example, consider a class named 'Dog'. To create an instance of this class, you would write: Dog myDog = new Dog(); Here, 'Dog()' is the constructor of the class, and 'myDog' is a variable that holds the reference to the new object.

The process of object instantiation involves several steps. First, the Java Virtual Machine (JVM) allocates memory for the new object on the heap. The heap is a part of memory where Java runtime instances are allocated. The JVM then calls the constructor method of the class. The constructor method initialises the new object and sets the initial state of its instance variables. If the class does not define a constructor, the JVM provides a default constructor.

Once the object is created, you can use the dot operator (.) to access its instance variables and methods. For example, if the 'Dog' class has a method named 'bark', you can call this method on the 'myDog' object like this: myDog.bark();

In summary, object instantiation in Java is a process that involves memory allocation, constructor invocation, and initialisation of instance variables. It is a fundamental concept in object-oriented programming and is essential for creating and using objects in Java.