Module 6 quiz on methods and classes

Module 6 quiz on methods and classes



1. Making instance variables of a class private

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Ans:-  
is an application of abstraction and protects against object users gaining direct access to object state.
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2. A class method such as addMonthlyBonus(double x) that receives an input parameter and uses it to change the instance variable of an object is called a

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Ans:- 

mutator method
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3. Select all of the following method definitions below that
employ the correct syntax to define a constructor for the class Vehicle. A partial list of the class instance variables includes:

int year;
double odometer;
...

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Ans:- 

public Vehicle(){
}


public Vehicle(double mileage, int year){
  this(mileage);
  this.year = year;
}

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4. When a constructor is written for the class (select all that apply)

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Ans:- 
the default constructor must be recreated if it is to be used by client programs.

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5. When calling one constructor from another constructor


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Ans:-


the keyword this is used and must be the first line of the constructor code.

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6. Consider these two methods which are part of the Student class. Assume that age is a private instance variable of the class.


public void setAge(int years, int months){
   age = years * 12 + months;
}

public void setAge(int months){
   age = months;
}

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Ans:- mutators
overloading
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