Java OCA OCP Practice Question 1172

Question

Which statement about a no-argument constructor is true?

  • A. The Java compiler will always insert a default no-argument constructor if you do not define a no-argument constructor in your class.
  • B. In order for a class to call super() in one of its constructors, its parent class must explicitly implement a no-argument constructor.
  • C. If a class extends another class that has only one constructor that takes a value, then the child class must explicitly declare at least one constructor.
  • D. A class may contain more than one no-argument constructor. 


C.

Note

Option A is incorrect because Java only inserts a no-argument constructor if there are no other constructors in the class.

Option B is incorrect because the parent can have a default no-argument constructor, which is inserted by the compiler and accessible in the child class.

Option D is incorrect.

A class that contains two no-argument constructors will not compile because they would have the same signature.

Option C is correct.

If a class extends a parent class that does not include a no-argument constructor, the default no-argument constructor cannot be automatically inserted into the child class by the compiler.

The developer must explicitly declare at least one constructor and explicitly define how the call to the parent constructor is made.




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