Writing Constructors for Subclasses

AP Computer Science A· difficulty 3/5

public class Vehicle {
    private int wheels;
    public Vehicle(int w) { wheels = w; }
}
public class Car extends Vehicle {
    private String model;
    public Car(String m) {
        model = m;
    }
}

What happens when you try to compile Car?

A
$Warning but compiles$
B
$Compiles successfully$
C
$Compile error: no default constructor in Vehicle to call implicitly$
check_circle
D
$Runtime error when instantiated$

Explanation

When a subclass constructor does not explicitly call super(...), Java inserts an implicit super() with no arguments. Since Vehicle has no zero-argument constructor, this fails to compile.

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