Down Casting in Java: Definition, Rules, and Examples
Down Casting in Java Down Casting is the process of converting a superclass reference (that actually refers to a subclass object) into a subclass reference. Key Points Down casting is also known as explicit casting. It must be performed by the programmer using a cast operator. The compiler does not perform down casting automatically. Up casting must occur before down casting. If down casting is done without a valid up cast, it results in a ClassCastException at runtime. Example class Parent { void show() { System.out.println("Parent method"); } } class Child extends Parent { void display() { System.out.println("Child method"); } } Parent p = new Child(); // Up casting Child c = (Child) p; // Down casting c.show(); // Allowed c.display(); // Allowed Invalid Down Casting Parent p = new Parent(); Child c = (Child) p; // ClassCastException Why Down Casting Is Risky Per...