Upcasting and Downcasting

Type conversion in inheritance

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Upcasting & Downcasting

Upcasting is safe and implicit. Downcasting is explicit and requires instanceof check.

Code Examples

Safe and unsafe type casting

java
1
2Animal a = new Dog(); // Upcasting
3
4if (a instanceof Dog) {
5    Dog d = (Dog) a; // Downcasting
6    d.bark();
7}
8

Use Cases

  • Generic processing
  • Framework internals
  • Runtime object handling

Common Mistakes to Avoid

  • Casting without instanceof
  • Assuming all parents are children