IT1908 Method Overloading Quiz

Questions and Answers

What allows overloaded methods to be differentiated?

Both B and C (correct)

Return type

Type of arguments

Number of arguments

In Java, you can declare two methods with the same signature if they have different return types.

False

What is the output of the following code snippet: `public static void main(String[] args) { int num = 1; newNumber(2); System.out.println(num); }`?

Autoboxing is the automatic conversion between primitive types and their corresponding ______ classes.

object wrapper Signup and view all the answers

What does Java use when the primitive type version of a method is not present?

Autoboxing Signup and view all the answers

What constitutes a method's signature?

Method name and parameter types Signup and view all the answers

What happens when the primitive type version is present in method overloading?

Java does not need to perform autoboxing Signup and view all the answers

Method overloading can occur with different method signatures that have the same name.

True Signup and view all the answers

Study Notes

Method Overloading

Overloading methods requires different parameter types or different number of parameters.
Duplicate method declarations with the same name, type, and number of parameters are not permitted.
Example of invalid overload:
- public int draw(int i) { } does not compile if public void draw(int i) { } exists.

Method Parameters and Arguments

Parameters are defined within method declarations; they act as placeholders for the actual values (arguments).
Arguments are the actual values supplied when the method is invoked.
Example usage:
- computeSalePrice(37.50, 0.15) passes 37.50 and 0.15 as arguments to computeSalePrice.

Java Pass-by-Value

Java uses a pass-by-value mechanism, meaning a copy of the variable is passed, not the variable itself.
Modifications to the parameter inside the method do not affect the variable in the calling method.
Example: In main(), changing num inside newNumber(int num) does not alter num in main().

Autoboxing

Autoboxing refers to automatic conversion between primitive types and their corresponding wrapper classes (e.g., int to Integer).
If a corresponding primitive method is absent, Java performs autoboxing to accommodate object types.
Example scenarios:
- If draw(Integer i) is called with a primitive int (draw(10)), autoboxing converts 10 to Integer.

Method Signature

A method's signature consists of its name and parameter types, which uniquely identify it.
Example signature:
- computeSalePrice(double, double) distinguishes it based on parameter types.

Execution Outputs

When calling overloaded methods, the method invoked depends on the parameters provided.
Output specifics from examples:
- Calling draw(int i) outputs int.
- Calling draw(Integer i) outputs Integer.

Overloaded Method Examples

Various overloaded methods can exist with same name but different signatures:
- public void draw(String s) { }
- public void draw(int i) { }
- public void draw(int i, double f) { }

Effective Overloading

Method overloading allows developers to write cleaner and more intuitive code by using the same method name for similar actions while distinguishing based on parameter usage.

Description

Test your knowledge on method overloading in programming. This quiz will challenge you to understand how methods can be differentiated by the number and types of arguments. Explore key concepts related to passing information to methods and their declarations.