Declaration And Access Control MCQ

Test your knowledge with important Declaration And Access Control MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30 + more Declaration And Access Control MCQs at Bissoy

• What can directly access and change the value of the variable qusNo?<br><pre><code class="java">package com.mypackage;public class Test{ private int qusNo = 100;}</code></pre>
  ক

  Only the Test class.

  খ

  Any class.

  গ

  Any class in com.mypackage package.

  ঘ

  Any class that extends Test.

  ঙ

  None of these
• Name the keyword that makes a variable belong to a class, rather than being defined for each instance of the class.
  ক

  static

  খ

  final

  গ

  abstract

  ঘ

  native

  ঙ

  volatile
• Choose the correct statement<br><pre><code class="java">public class Circle{ private double radius; public Circle(double radius){ radius = radius; }}</code></pre>
  ক

  The program has a compilation error because it does not have a main method.

  খ

  The program will compile, but we cannot create an object of Circle with a specified radius. The object will always have radius 0.

  গ

  The program has a compilation error because we cannot assign radius to radius.

  ঘ

  The program does not compile because Circle does not have a default constructor.
• A method within a class is only accessible by classes that are defined within the same package as the class of the method. Which one of the following is used to enforce such restriction?
  ক

  Declare the method with the keyword public.

  খ

  Declare the method with the keyword private.

  গ

  Declare the method with the keyword protected.

  ঘ

  Do not declare the method with any accessibility modifiers.

  ঙ

  Declare the method with the keyword public and private.
• A package is a collection of
  ক

  Classes

  খ

  Interfaces

  গ

  Editing tools

  ঘ

  Classes and Interfaces

  ঙ

  Editing tools and Interfaces
• Which statements are most accurate regarding the following classes?<br><pre><code class="java">class A{ private int i; protected int j;}class B extends A{ private int k; protected int m;}</code></pre>
  ক

  An object of B contains data fields i, j, k, m.

  খ

  An object of B contains data fields j, k, m.

  গ

  An object of B contains data fields j, m.

  ঘ

  An object of B contains data fields k, m.
• Determine output:<br><pre><code class="java">public class InitDemo{static int i = demo();static{ System.out.print(i); }InitDemo(){System.out.print("hello1");}public static void main(String... args){ System.out.print("Hello2");} static int demo(){ System.out.print("InsideDemo");return 10;}}</code></pre>
  ক

  Compilation error.

  খ

  IllegalArgumentException is thrown at runtime.

  গ

  InsideDemo 10 Hello2

  ঘ

  Hello2 InsideDemo 10

  ঙ

  InsideDemo 10 Hello2 hello1
• What is the result of compiling and running the following code?<br><pre><code class="java">public class Tester{static int x = 4;int y = 9; public Tester(){System.out.print(this.x); // line 1printVariables();}public static void printVariables(){System.out.print(x); // line 2System.out.print(y); // line 3}public static void main(String... args) { // line 4new Tester();}}</code></pre>
  ক

  Compile error at line 1 (static x must be only accessed inside static methods)

  খ

  Compile error at line 3 (static methods can't make reference to non-static variables)

  গ

  Compile error at line 4 (invalid argument type for method main)

  ঘ

  49

  ঙ

  Compile error at line 2 (must access x by writing Tester.x)
• What is the result of compiling and running the following code?<br><pre><code class="java">public class Tester{static int x = 4;public Tester(){System.out.print(this.x); // line 1Tester();}public static void Tester(){ // line 2System.out.print(this.x); // line 3}public static void main(String... args){ // line 4new Tester();}}</code></pre>
  ক

  Compile error at line 1 (static x must be only accessed inside static methods)

  খ

  Compile error at line 2 (constructors can't be static)

  গ

  Compile error at line 3 (static methods can't invoke this)

  ঘ

  Compile error at line 4 (invalid argument type for method main )

  ঙ

  44
• Suppose a class has public visibility. In this class we define a protected method. Which of the following statements is correct?
  ক

  This method is only accessible from inside the class itself and from inside all subclasses.

  খ

  In a class, you cannot declare methods with a lower visibility than the visibility of the class in which it is defined.

  গ

  From within protected methods you do not have access to public methods.

  ঘ

  This method is accessible from within the class itself and from within all classes defined in the same package as the class itself.
• Which keyword is used to explicitly specify that a method should be overridden in a subclass?
  ক

  override

  খ

  extends

  গ

  super

  ঘ

  implement
• What is the access level of a class member declared as protected in Java?
  ক

  public

  খ

  protected

  গ

  private

  ঘ

  package-private
• Which keyword is used to declare a method that cannot be overridden in a subclass?
  ক

  final

  খ

  static

  গ

  super

  ঘ

  this
• In Java, what is the purpose of the final keyword when applied to a class?
  ক

  It makes the class non-final.

  খ

  It prevents subclassing.

  গ

  It makes the class constant.

  ঘ

  It makes the class abstract.
• Which access modifier restricts a class member's visibility to only the same class, its package, and subclasses?
  ক

  default

  খ

  private

  গ

  public

  ঘ

  protected
• What keyword is used to declare a variable that can be accessed without creating an instance of the class?
  ক

  static

  খ

  final

  গ

  public

  ঘ

  this
• Which access modifier allows a class member to be accessed from any class in the same package but not from outside?
  ক

  protected

  খ

  private

  গ

  public

  ঘ

  default
• In Java, what is the purpose of the final keyword when applied to a method?
  ক

  It makes the method non-final.

  খ

  It allows method overriding.

  গ

  It makes the method constant.

  ঘ

  It makes the method static.
• What keyword is used to declare a method that is implemented in a subclass to provide a specific implementation?
  ক

  abstract

  খ

  override

  গ

  implement

  ঘ

  extends
• In Java, which access modifier allows a class member to be accessed from any class, even outside the package?
  ক

  public

  খ

  protected

  গ

  private

  ঘ

  package-private
• What access modifier allows a class member to be accessed from any class in the same package or any subclass?
  ক

  protected

  খ

  private

  গ

  public

  ঘ

  default
• Which of the following is not an access modifier in Java?
  ক

  abstract

  খ

  final

  গ

  transient

  ঘ

  static
• In Java, what access modifier is used to specify that a class member can be accessed only within its class?
  ক

  protected

  খ

  private

  গ

  public

  ঘ

  package-private
• What is the keyword used to declare a class that cannot be instantiated and can only be extended?
  ক

  final

  খ

  const

  গ

  static

  ঘ

  abstract
• Which access modifier allows a class member to be accessed within the same package and its subclasses?
  ক

  private

  খ

  public

  গ

  protected

  ঘ

  package-private
• What is the access level of a class member declared as private in Java?
  ক

  public

  খ

  protected

  গ

  private

  ঘ

  package-private
• Which keyword is used to define a superclass's method that is overridden by a subclass method?
  ক

  override

  খ

  extends

  গ

  super

  ঘ

  implement
• In Java, what is the purpose of the static keyword when applied to a variable?
  ক

  It makes the variable non-static.

  খ

  It initializes the variable.

  গ

  It allows access from any class.

  ঘ

  It makes the variable constant.
• Which of the following access modifiers restricts a method or variable's access to the same package only?
  ক

  public

  খ

  protected

  গ

  private

  ঘ

  package-private
• What keyword is used to declare a method that can be called without creating an instance of the class?
  ক

  static

  খ

  final

  গ

  public

  ঘ

  this