Day 11

What is the difference between method overloading and method overriding?

• Method overloading is static polymorphism, while method overriding is dynamic polymorphism.

• Method overloading is used in inheritance, while method overriding is used in abstraction.

• Method overloading is when a subclass provides a different implementation of a method, while method overriding is when a subclass has multiple methods with the same name.

• Method overloading is used for access control, while method overriding is used for code reusability.

Answer explanation

Method overloading is static polymorphism, while method overriding is dynamic polymorphism

Which of the following is not a benefit of using packages in Java?

• Encapsulation and information hiding

• Improved code reusability

• Easy management of large projects

• Faster execution of Java programs
  

Answer explanation

Faster execution of Java programs

Which of the following is/are not advantages of packages?

• packages avoid name clashes.

• classes even though they are visible outside their package, can have visible to packages only

• we have hidden classes that are used by the packages, but not bisible outside.

• all the above

Answer explanation

classes even though they are visivle outside theor package,can have visible to packages only

// Note static keyword after import.

import static java. lang. System.*;

class StaticImportDemo

{

public static void main(String args[])

{

out.println("wipro training");

}

}

• Wipro training

• compile Error

• Runtime error

• None of the above

Which keyword is used to establish inheritance in Java?

• inherits

• extends

• inheritsFrom

• implements

Predict the output of the following program.?

abstract class demo

{

public int a;

demo()

{

a = 10;

}

abstract public void set();

abstract final public void get();

}

class Test extends demo

{

public void set(int a)

{

this.a = a;

}

final public void get()

{

System.out.println("a = " + a);

}

public static void main(String[] args)

{

Test obj = new Test();

obj.set(20);

obj.get();

}

}

• Compilation error

• a=10

• a=20

• Runtime error

Can an interface contain variables?

• Yes, only static variables.

• Yes, only final variables.

• No, interfaces cannot have variables

• Yes, but they must be final and static.

Multiple inheritance allows a class to inherit from

• Only one base class

• Two or more base classes

• Two base classes but with some restrictions

• None of the above

What is the primary advantage of using inheritance in object-oriented programming?

• Faster execution speed

• Improved memory management

• Code reusability

• Faster execution speed

Find which of the following uses encapsulation?

• void main(){

  int a;

  void fun() { int a=10;

  System.out.println(a);

  fun(); }

• class student {

  int a;

  public void disp(){

  System.out.println(a);

  } }

• class student{

  int a;

  public int b; };

• static topper() {

  char name[10];

  public int marks; }