» » Method overloading interview questions java

1.What is Method in java?

  • Method is a sub block of a class that contains logic of that class.
  • logic must be placed inside a method, not directly at class level, if we place logic at class level compiler throws an error.
  • So class level we are allowed to place variables and methods.
  • The logical statements such as method calls, calculations and printing related statements must be placed inside method, because these statements are considered as logic. 
  • For more information @ Methods in java



  1. package com.instanceofjava;
  2. class sample{
  3.  
  4. int a;
  5. int b;
  6.  
  7. System.out.println("instance of java"); // compiler throws an error.
  8.  
  9. }
  10.  

  1. package com.instanceofjava;
  2. class sample{
  3.  
  4. static int a=10;
  5.    
  6. public static void main(String args[]){

  7. System.out.println(a); // works fine,prints a value:10
  8.  
  9.  }
  10. }

2.What is meant by method overloading in java?


  • Defining multiple methods with same name is known as polymorphism.
  • Defining multiple methods with same name and with different arguments known as method overloading.

  1. package com.instanceofjava;
  2. class A{
  3.  
  4. public void show(int a){
  5. System.out.println("saidesh");
  6. }
  7.  
  8. public void show(int a,int b){
  9. System.out.println("ajay");
  10. }
  11.  
  12. public void show(float a){
  13. System.out.println("vinod");
  14. }
  15. public static void main(String args[]){
  16.  
  17. A a=new A();
  18.  
  19. a.show(10);
  20. a.show(1,2);
  21. a.show(1.2);
  22.  
  23. }
  24. }
Output:

  1. saidesh
  2. ajay
  3. vinod


3.What are the other names for method overloading?


  • Method overloading also known as static polymorphism or compile time polymorphism because at compile time itself we can tell which method going to get executed based on method arguments.
  • So method overloading also called as static binding. 

4.What are the basic rules of method overloading?

  • Defining a method with same name and differ in number of arguments
  • Defining a method with same name and differ in type of arguments
  • Defining a method with same name and differ in order of type of arguments
  • Return type of the method not involved in method overloading.

5.Can we overload static methods in java?

  • Yes. We can overload static methods in java.
  • Method overriding is not possible but method overloading is possible for static methods.
  • Before that lets see about method overloading in java.
  • lets see an example java program which explains static method overloading.
  1. class StaticMethodOverloading{
  2.  
  3. public static void staticMethod(){
  4.  
  5. System.out.println("staticMethod(): Zero arguments");
  6.  
  7.  
  8. public static void staticMethod(int a){
  9.  
  10. System.out.println("staticMethod(int a): one argument");
  11.  
  12.  
  13. public static void staticMethod(String str, int x){
  14.  
  15. System.out.println("staticMethod(String str, int x): two arguments");
  16.  
  17. }
  18.  
  19. public static void main(String []args){
  20.   
  21.   StaticMethodOverloading.staticMethod();
  22.   StaticMethodOverloading.staticMethod(12);
  23.   StaticMethodOverloading.staticMethod("Static method overloading",10);
  24.  
  25. }
  26. }


 Output:

  1. staticMethod(): Zero arguments
  2. staticMethod(int a): one argument
  3. staticMethod(String str, int x): two arguments


6.Can we overload main method in java?

Yes we can overload main method in java

Java Program to overload main method in java

  1. class mainMethodOverloading{
  2.  
  3. public static void main(boolean x){
  4.  
  5. System.out.println("main(boolean x) called ");
  6.  
  7.  
  8. public static void main(int x){
  9.  
  10. System.out.println("main(int x) called");
  11.  
  12.  
  13. public static void main(int a, int b){
  14.  
  15. System.out.println("main(int a, int b) called");
  16.  
  17. }
  18.  
  19. public static void main(String []args){
  20.    
  21.  
  22. System.out.println("main(String []args) called ");
  23.  
  24.   mainMethodOverloading.main(true);
  25.   mainMethodOverloading.main(10);
  26.  mainMethodOverloading.main(37,46);
  27.  
  28.  
  29. }
  30. }




 Output:

  1. main(String []args) called
  2. main(boolean x) called
  3. main(int x) called
  4. main(int a, int b) called

method overloading interview questions





7.Can we overload constructors in java?

  • Yes we can overload constructor in java

  1. package instanceofjava;
  2. class ConstructorChaining{
  3. int a,b 
  4. ConstructorChaining(){
  5. this(1,2);
  6.  System.out.println("Default constructor");
  7.  
  8.  
  9. ConstructorChaining(int x , int y){
  10.  
  11. this(1,2,3); 
  12. a=x;
  13. b=y;
  14.  System.out.println("Two argument constructor");
  15.  
  16. }
  17.  
  18. ConstructorChaining(int a , int b,int c){
  19.  System.out.println("Three argument constructor")
  20.  
  21. public static void main(String[] args){
  22.  
  23.  ConstructorChaining obj=new ConstructorChaining();
  24.   System.out.println(obj.a);
  25.   System.out.println(obj.b);
  26.  
  27. }
  28. }


You Might Like:



Instance Of Java

We will help you in learning.Please leave your comments and suggestions in comment section. if you any doubts please use search box provided right side. Search there for answers thank you.
«
Next
Newer Post
»
Previous
Older Post

No comments

Leave a Reply

Select Menu