Overloading vs overriding

Question

I heared both are concepts of polymorphism .
overloading is compile time polymorphism and overriding is run-time .
I need a brief explanation with real time example
Thank you !!

Answer 1

Overriding is when a subclass takes a method of its parent class and overrides it so that the output of that method will be different from its initial output.

Example (Overriding):

Class Parent
using_Mouth(){
print "You will do your homework"
}
//Outputs You will do your homework

Class Child Extend Parent
using_Mouth(){
print "I will not do my homework"
}
//Outputs I will not do my homework

-Above the intial output of the method is the top one but then the subclass overrides it to give a different output but using the same method.

-The syntax is obviously not correct but it's simplified so that you can understand

Overloading is when you need a method to do the same functionality but with different parameters.

Example (Overloading):

int calculate_ADD(int var1, int var2){
return var1 + var2
}
//Outputs the sum of two integers

double calculate_ADD(double var1, double var2){
return var1 + var2
}
//Outputs the sum of two doubles

-Above the method just has the function to add two variables together and that's why it's a perfect candidate for Overloading because you can then simply switch the data types and you'd get the same functionality, the sum of two variables

-Again, not correct syntax but hopefully you'll understand better

Answer 2

I found good explanations and examples here:
http://stackoverflow.com/questions/2469767/java-overloading-and-overriding

Answer 3

Overload when the methods had same name and retun type but different argument list.
Override when a subclass override the method of superclass or interface annotate with @override.
Example:
Overload:

String greetings(){
System.out.println("Hello World!");
}

String greetings(String name){
System.out.println("Hello "+name+"!");
}

Override:

class A{
String greetings(){
System.out.println("Hello world!");
}
}

class B extends A{
@Override
String greetings(){
System.out.println("Hi there!");
}
}