Question

Where the OOD approach is specified use a separate test class to create your objects.

1. Odd.java Write a program that takes an integer input and prints an output messages stating whether or not the user enters an odd positive number.

2. Guessing.java: Use OOD: Write a number guessing program. Assign a value to a variable called number at the top of the program. Give a prompt that asks for five guesses. See whether any of the guesses matches the number and then print an appropriate message if one does.
3. GuessingTest

4. Tax.java: Use OOD: Write a tax calculation program. Prompt the user to input two salaries for a family and output their combined tax bill. A family pays no tax if its income is less than 15000 euro. The family pays a 10% tax if the combined salaries are for 15000 euro through 19,999 euro, or a 20% tax if the combined salaries are from 20000 euro through 29,999. Otherwise the family pays a 30% tax.
5. TaxTest

6. GreaterThan.java Write a program with a main method that calls a method called greaterThan, that takes two integer arguments and returns 1, if the first is greater than the second, and 0 otherwise.

7. Initals.java : Use OOD: Write a program that asks the user for two initials. Print a message telling the user whether the first initial falls alphabetically before the second.
8. InitialsTest

Answer 1

Kindly upvote if this helped


As there are multiple questions answering initial 2 Questons. Kindly create seperate questions for multiple questions.

1)

Odd.java

import java.util.Scanner;

public class Odd {
  public void OddTest() {
                Scanner sc = new Scanner(System.in);
                System.out.println("Enter a number");
                int input = sc.nextInt();
                sc.close();
                if( input%2!=0 && input>0 ) {  // number is odd and positive
                        System.out.println("Number is an odd positive number");
                }else {
                        System.out.println("Number is either even or negative");
                }
  }
}

OddTest.java

class OddTest{
        public static void main(String[] args) {
                Odd d = new Odd();
                d.OddTest();
        }
}

2.)

Guessing.java

import java.util.ArrayList;
import java.util.Scanner;

public class Guessing{
        public int getNumber() {
                return number;
        }
        int number = 10;
        public void GuessNumber() {
                ArrayList<Integer> numbers = new ArrayList<Integer>(); // arrayList to store the guesses
                Scanner sc = new Scanner(System.in);
                int num;
                System.out.println("Guess the number");
                for(int i=1;i<=5;i++) {
                        num = Integer.parseInt(sc.nextLine());
                        numbers.add(num);
                }
                sc.close();
                boolean flag = true;
                for(int i=0;i<5;i++) {
                        if(numbers.get(i) == getNumber()) {
                                int t = i+1;
                                System.out.println("Guess number "+t+" matched");
                                flag = false;
                        }
                }
                if(flag) {
                        System.out.println("No guess successful");
                }
        }
}

GuessingTest.java

class GuessingTest{
        public static void main(String[] args) {
                Guessing g = new Guessing();
                g.GuessNumber();
        }
}

Snapshot for indent

Adding solution to other parts for student understanding

class Tax{
        public static void main(String[] args) {
                Scanner sc = new Scanner(System.in);
                System.out.println("Enter salary of 2 members");
                double s1 = Double.parseDouble(sc.nextLine());
                double s2 = Double.parseDouble(sc.nextLine());
                double income = s1+s2;
                double tax = 0;
                sc.close();
                if(income>=15000 && income < 20000) {
                        tax = income * 0.1; //10%
                }
                if(income>=20000 && income < 30000) {
                        tax = income * 0.2; //20%
                }
                if(income >=30000) {
                        tax = income * 0.3; //30%
                }
                System.out.println("Tax is "+tax);
        }
        
        
}


class Inte{
public static int greaterThan(int a , int b) {
                if(a>b) {
                        return 1;
                }
                return 0;
        }
        public static void main(String[] args) {
                greaterThan(10, 20);
        }
}



class Initials{
public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        System.out.println("Enter 2 initials");
        String a = sc.nextLine();
        String b = sc.nextLine();
        if(a.compareTo(b)>0) {
                System.out.println(a+ " falls after "+b);
        }else if(a.compareTo(b)<0) {
                System.out.println(a+ " falls before "+b);
        }else {
                System.out.println("Both are equal");
                sc.close();
        }
}       
}