U1 Primitives • 6 min read

import java.util.*;
public class TypeTest {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        
        System.out.println("Enter an int: ");
        try {
            int int_val = scan.nextInt();
            System.out.println(int_val);
            System.out.println("Using the int value by doubling it: " + int_val * 2); //I can multiply the int value by an int, I cannot multiply a String or it would throw a type conflict
        }
        catch (Exception e) {
            System.out.println("Not an int, int is in the form: 194");
        }

        
        System.out.println("Enter a double: ");
        try {
            double double_val = scan.nextDouble();
            System.out.println(double_val);
            System.out.println("Using the double value by doubling it: " + double_val * 2.0); //I can multiply the double value by both a double or an int, I cannot multiply a String or it would throw a type conflict
        }
        catch (Exception e) {
            System.out.println("Not a double, double is in the form: 1.94");
        }

        
        System.out.println("Enter a boolean: ");
        try {
            boolean bool_val = scan.nextBoolean();
            System.out.println(bool_val);
            if (bool_val) //
            {
                System.out.println("It worked");
            }
            else
            {
                System.out.println("It didn't work");
            }
        }
        catch (Exception e) {
            System.out.println("Not a boolean, boolean is in the form: true/false");
        }

        while (true)
        {
            System.out.println("Enter a char: ");
            String char_val = scan.next();
            if (char_val.length() == 1)
            {
                System.out.println(char_val);
                break;
            }    
            else
            {
                System.out.println("Not a char, char is in the form: a (only one character long)");
            }
        }

        System.out.println("Enter a String: ");
        try {
            String str_val = scan.next();
            System.out.println(str_val);
            System.out.println("Output the last character of the String: " + str_val.charAt(str_val.length() - 1));//String is an array of characters so you can get the value of an element in the String
        }
        catch (Exception e)
        {
            System.out.println("How did you mess this up?");
        }
        scan.close();
    }
}

TypeTest.main(null);

Usage of Primitives

Applying primitive data types

import java.util.*;
public class Operations {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);

        System.out.println("Enter the temperature as a whole number in Fahrenheit");
        try {
            int temp1 = scan.nextInt();
            temp1 -= 32;
            int celsiuscon = (temp1-32) * 5/9;
            System.out.println(celsiuscon);
        }
        catch (Exception e)
        {
            System.out.println("Enter it as a whole number, no decimals");
        }

        
        System.out.println("Now enter the temperature as a decimal in Fahrenheit");
        try {
            Double temp1 = scan.nextDouble();
            temp1 -= 32;
            Double celsiuscon = temp1 * 5/9;
            System.out.println(celsiuscon);
        }
        catch (Exception e)
        {
            System.out.println("Enter it as a decimal");
        }



    }
}

Operations.main(null);

Enter the temperature as a whole number in Fahrenheit
50
Now enter the temperature as a decimal in Fahrenheit
50.55555555555556