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The correct option is (a) Constructor can’t be overloaded in KOTLIN

The EXPLANATION: Kotlin LANGUAGE allows constructor OVERLOADING. This is a basic feature for the constructors. The constructor overloading allows the OBJECT to be initialized according to the user.

Right answer is (c) classname objectname= new classname();

The best I can explain: The syntax for object CREATING in java with calling a constructor for is it is as in OPTION c. The syntax must CONTAIN the classname FOLLOWED by the object name. The keyword new must be used and then the constructor CALL with or without the parameters as required.

Correct choice is (b) A function which is called whenever an object is created to initialize the members

Easy EXPLANATION - The constructors are special type of functions which are called whenever an object is created. This is to initialize the DATA members of the CLASS. The constructor allocates memory SPACE for all the data members.

Correct choice is (a) A FUNCTION which is called just before the objects are destroyed

Best EXPLANATION: The DESTRUCTORS are special functions which are called just before an object is destroyed. This functions is responsible to free all the ALLOCATED resources to the object. Objects are destroyed WHENEVER those go out of scope.

Right OPTION is (d) CLASSNAME()

The EXPLANATION: The constructors must contain only the CLASS name. The class name is followed by the blank parenthesis or we can have PARAMETERS if some values are to be passed.

Correct answer is (c) ~classname()

The explanation: The destructor MUST have same NAME as that of the CORRESPONDING CLASS. The class name should be preceded by the TILDE symbol (~).

Right option is (a) First the CONSTRUCTOR of parent classes are called in sequence of INHERITANCE

To explain: First the constructor of parent CLASS are called. The order in which the parent class CONSTRUCTORS are called is same in the sequence of inheritance used.

Right OPTION is (d) REVERE of the order of CONSTRUCTOR call

To EXPLAIN: The destructors are called in the reverse order as that of the constructors being called. This is DONE to ensure that all the resources are released in sequence. That is, the derived class destructors will be called first.

Right choice is (b) Can’t have any argument

Easiest explanation - The destructors doesn’t have any arguments. The destructors have to be called implicitly WHENEVER an object goes out of SCOPE. The USER can’t pass argument to the IMPLICIT CALL.

Right option is (c) Can be implicit or explicit

Easy explanation - The destructors are usually called implicitly whenever an object GOES out of SCOPE. The destructors can also be called explicitly if REQUIRED. The CALL must be MADE, implicitly or explicitly.

Right answer is (a) ALWAYS equal to NUMBER of CONSTRUCTORS called

The explanation is: DESTRUCTOR will be called only to free the resources allocated for an object. The resources are allocated only the constructor for an object is called.

Right answer is (B) The destructor must be public

The BEST explanation: The destructor must be public for explicit calls. If it is made PRIVATE or PROTECTED then it won’t be ACCESSIBLE outside the class. There is no restriction of definition the destructor outside the class.

Right OPTION is (b) False

Explanation: EVEN if the CLASS have 4 constructors, only one would be used. And only one DESTRUCTOR is allowed.

Correct choice is (c) Destructors can’t be overloaded

The best I can explain: The destructors can NEVER be overloaded. The destructors doesn’t have arguments. And to get overloaded, they MUST have different SIGNATURE. This is not POSSIBLE if arguments are not allowed.

The correct choice is (d) Doesn’t have a return type

The best explanation: The destructors are intended to FREE the memory space. And all the resources that were ALLOCATED for the OBJECT. The return VALUE is not supported SINCE only memory has to be made free.

The correct choice is (b) False

Best EXPLANATION: The destructors can be called only after the constructor CALLS. It is not a MANDATORY rule but the DELETION can only take place if there is something CREATED using the constructor.

Right ANSWER is (a) A special function that is called to free the resources, acquired by the object

Easiest explanation - It is USED to free the resources that the object might had used in its LIFESPAN. The DESTRUCTORS are called implicitly whenever an object’s life ends.

Correct option is (d) Just before the end of OBJECT life

Easiest explanation - The DESTRUCTOR is called just before the object go out of scope or just before its life ends. This is done to ensure that all the resources reserved for the object are USED and at last, are made free for others.

Right ANSWER is (a) It doesn’t have destructors

The explanation is: It doesn’t have destructors. Since an ABSTRACT class don’t have CONSTRUCTORS, and hence can’t have instances. Having this case, the abstract CLASSES don’t have destructors too, because that would be of no use here.

Correct choice is (a) ~C() then ~B() then ~A()

The best I can EXPLAIN: The destructors are always called in the reverse order of how the CONSTRUCTORS were called. Here class A constructor WOULD have been created FIRST if Class C object is declared. Hence class A destructor is called at last.

Right answer is (a) Just before end of program

The BEST I can explain: This is because the lifespan of global object is from start of the program, TILL the end of the program. And hence program end is the end of global object too. Just before the end of program, the destructor will be CALLED to free the ACQUIRED resources by the objects.

Correct option is (C) Destructors are preceded with a tilde (~) symbol, and constructor doesn’t

The best EXPLANATION: The destructors are preceded with the tilde (~) symbol. The NAME is same as that of the class. These also doesn’t have any return type.

Correct option is (b) Virtual

Easiest explanation - The destructors can be virtual. It is actually advised to keep the destructors virtual ALWAYS. This is DONE to suppress the problems that may ARISE if inheritance is involved.

Right option is (c) REVERSE

Easiest explanation - The destructors are ALWAYS called in reverse order no matter which destructor it is. This is done to ensure that all the RESOURCES are able to get free. And no RESOURCE is KEPT busy.

The correct answer is (a) When class contains some pointer to MEMORY allocated in class

Explanation: This is always advised to have user defined destructor when pointers are involved in class. This is usually done to ensure that the memory, that was allocated dynamically, GETS FREE after use and doesn’t cause memory LEAK.

The CORRECT choice is (d) There can be only one destructor in a class

The explanation is: This is so because the DESTRUCTORS can’t be OVERLOADED. And the destructor must have the same name as that of class with a tilde symbol preceding the name of the destructor. Hence there can be only one destructor in a class. Since more than one FUNCTION with same name and signature can’t be PRESENT in same scope.

Right option is (a) Destructor is not called

The best I can explain: The destructor is never called in this situation. The CONCEPT is that when an object is passed by REFERENCE to the function, the CONSTRUCTOR is not called, but only the main object will be used. Hence no destructor will be called at end of function.