Certified Java Programmer Mock Exam

Question 1

class A {A(int i) {}}  // 1
class B extends A {}   // 2

Which of the following statements are true?

a.	The compiler attempts to create a default constructor for class A.
b.	The compiler attempts to create a default constructor for class B.
c.	Compile-time error at 1.
d.	Compile-time error at 2.

Which of the following modifiers can be applied to a constructor?

Which of the following techniques can be used to prevent the instantiation of a class by any code outside of the class?

a.	Do not declare any constructors.
b.	Do not use a return statement in the constructor.
c.	Declare all constructors using the keyword void to indicate that nothing is returned.
d.	Declare all constructors using the private access modifier.
e.	None of the above.

Which of the following modifiers can be applied to a constructor?

Which of the following statements are true?

a.	The compiler will create a default constructor if no other constructor is declared.
b.	The default constructor takes no arguments.
c.	If a class A has a direct superclass, then the default constructor of class A invokes the no-argument constructor of the superclass.
d.	The default constructor declares Exception in the throws clause.
e.	The default constructor is always given the private access modifier.
f.	The default constructor is always given the public modifier.
g.	The default constructor is always given default package access.

Suppose that the compiler generates a default constructor for a class. If a compile-time error is to be avoided, which of the following must be true?

a.	The superclass must not have any constructor other than a default constructor.
b.	The superclass must not have an accessible no-argument constructor.
c.	The no-argument superclass constructor must not have a throws clause that includes a checked exception.
d.	The no-argument superclass constructor must be declared private.
e.	None of the above

class A {A() throws Exception {}} // 1
class B extends A {B() throws Exception {}} // 2
class C extends A {} // 3

Which of the following statements is true?