Day 21: Generics - HackerRank 30 days of code solution

Objective
Today we're discussing Generics; be aware that not all languages support this construct, so fewer languages are enabled for this challenge.

Task
Write a single generic function named printArray; this function must take an array of generic elements as a parameter (the exception to this is C++, which takes a vector). The locked Solution class in your editor tests your function.

Note: You must use generics to solve this challenge. Do not write overloaded functions.

Input Format

The locked Solution class in your editor will pass different types of arrays to your printArray function.

Constraints

• You must have exactly  function named printArray.

Output Format

Your printArray function should print each element of its generic array parameter on a new line.

Solution :

import java.util.*;

class Printer <T> {

    /**

    *    Method Name: printArray

    *    Print each element of the generic array on a new line. Do not return anything.

    *    @param A generic array

    **/

    

    // Write your code here

  public static <Element> void printArray(Element[] array) {

        for (Element element : array) {

            System.out.println(element);

        }

    }

}

public class Generics {

    

    public static void main(String args[]){

        Scanner scanner = new Scanner(System.in);

        int n = scanner.nextInt();

        Integer[] intArray = new Integer[n];

        for (int i = 0; i < n; i++) {

            intArray[i] = scanner.nextInt();

        }

        n = scanner.nextInt();

        String[] stringArray = new String[n];

        for (int i = 0; i < n; i++) {

            stringArray[i] = scanner.next();

        }

        

        Printer<Integer> intPrinter = new Printer<Integer>();

        Printer<String> stringPrinter = new Printer<String>();

        intPrinter.printArray( intArray  );

        stringPrinter.printArray( stringArray );

        if(Printer.class.getDeclaredMethods().length > 1){

            System.out.println("The Printer class should only have 1 method named printArray.");

        }

    } 

}