What Are Two Types of Casting in Java?
🔹 1. Primitive Casting
This is casting between primitive data types (like int, double, float, etc.).
(a) Widening (Implicit) Casting
Happens automatically when converting a smaller type to a larger type.
Safe because there’s no data loss.
✅ Example
int x = 10;
double y = x; // int → double (automatic widening)
System.out.println(y); // 10.0
(b) Narrowing (Explicit) Casting
Needs explicit conversion using (type).
Risk of data loss.
✅ Example:
double d = 9.8;
int i = (int) d; // double → int (explicit narrowing)
System.out.println(i); // 9
🔹 2. Reference Casting (Object Casting)
This is casting between objects (classes/interfaces) in the inheritance hierarchy.
(a) Upcasting (Implicit)
Converting subclass → superclass.
Always safe.
✅ Example:
class Animal {}
class Dog extends Animal {}
Animal a = new Dog(); // Upcasting (automatic)
(b) Downcasting (Explicit)
Converting superclass → subclass.
Must be done explicitly.
Can throw ClassCastException if the object isn’t actually of that subclass.
✅ Example:
Animal a = new Dog();
Dog d = (Dog) a; // Downcasting (explicit)
