OOP) HashMaps Intro

import java.util.ArrayList;
import java.util.HashMap;

public class Main {

    public static void main(String[] args) {

        //creatinga  new ArrayList object
        ArrayList<Integer> test1 = new ArrayList<Integer>();

        //Using a Fir Loop to add values to th ArrayList
       for (int i = 0 ; i < 5 ; i++){
           test1.add(1);
       }

       //Printing the ArrayList
        for (int i = 0 ; i < 5 ; i++){
            System.out.println(test1.get(i));
        }

        //Using another For Loop to add more values to the ArrayList
        for (int i = 0 ; i < 10 ; i++){
            test1.add(2);
        }

        //Using the .get() Method to get the size of the ArrayList
        for (int i = 0 ; i < test1.size() ; i++){
            System.out.println(test1.get(i));
        }

        //Using a ForEach loop (A shortcut for writing a For Loop)
        System.out.println("Before the For Each Loop");
        for (Integer i : test1){
            System.out.println(i);
        }



        //Creating a new HashMap
        System.out.println();
        System.out.println("Testing HashMaps");
        HashMap<String, Integer> studentGrades = new HashMap<String, Integer>();

        studentGrades.put("Mark",87);
        studentGrades.put("Cassandra",95);
        studentGrades.put("Zenas",64);

        System.out.println(studentGrades.get("Mark"));

        //using .size() to get the number of elements in the HashMap
        System.out.println();
        System.out.println("This is the current size of the HashMap: " + studentGrades.size());

        //Accessing the keys as data
        System.out.println();
        System.out.println("I am outputting all of the current keys in the HashMap: " + studentGrades.keySet());

        //Using the ForEach Loop for a HashMap
        System.out.println();
        for (String i:studentGrades.keySet()){
            System.out.println(i + " has a grade of: " + studentGrades.get(i));
        }


    }
}