Object-Oriented Programming · Question 12 · Hard
What is the output of the following Java code?
static void m(Object o) { System.out.println("Object"); }
static void m(String s) { System.out.println("String"); }
// in main:
m(null);- Object
- String
- Compilation error: ambiguous call
- NullPointerException at runtime
Answer and explanation
Answer: B. String
Explanation: null can be passed to both overloads, so Java chooses the most specific one. String is a subclass of Object, so m(String) is chosen and "String" is printed.
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