Working With Classes

Finally finished my lab from yesterday and turned it in.  Here's the code from the two files.  I have a main java file and a sub java file that holds all of the operations.  The prime number may not be perfect in the sub file, but the logic is there.

There's also a menu that's called to choose what operation what you want done.



Main Class:===========================================================


//Christopher Smith
//CSC 15
//Lab 11 Classes Main

import java.util.Scanner;

public class lab11 {
    public static void main (String[] args){
    int pick, answer;
    int x = 0;
    int y = 0;
    
    Scanner kb = new Scanner(System.in);//keyboard input
    lab11calc my_subs = new lab11calc(); //object for sub class
    
    while (true) //infinite loop
    {
    System.out.println();
    System.out.println("---Menu---");
    System.out.println("1: Exit Program");
    System.out.println("2: Enter Values x & y");
    System.out.println("3: Find and display summation");
    System.out.println("4: Find and display product");
    System.out.println("5: Check primes");
     
    System.out.print("  Selection: ");
    pick = kb.nextInt();
    System.out.println();
     
    if (pick==1) return;
    else if (pick==2){
    System.out.println("Enter x");
    x = kb.nextInt();//enter x value
    System.out.println("Enter y");
    y = kb.nextInt();}//enter y value
    else if (pick==3){
    answer = my_subs.SumThem(x,y);//passes both x and y
    System.out.println("Summation is "+answer);}//returns ans from other class
    else if (pick==4){
    answer = my_subs.MultiplyThem(x,y);//passes both x and y
    System.out.println("Product is "+answer);}//displays returned answer from other class
    else if (pick==5){
         answer = my_subs.Prime(x,y);
    System.out.println("Prime is "+answer);}
    }
}
}

Sub Class:===============================================================

//Christopher Smith
//CSC 15
//Lab 11 Classes Subs

public class lab11calc {

    public int SumThem(int start, int end){//int start and end takes the x and y variables from main class
    int sum, count;
    sum = 0;
    for (count = start; count <= end; count++)
    {
    sum += count;
    }
    return sum; //return the sum of all the numbers
    }
    
    public int MultiplyThem(int start, int end){ //int start and end takes the x and y variables
    int product, count;
    product = 1;
    for (count = start; count <=end; count++)
    {
    product *= count;
    }
    return product;//return the product of all the numbers
    }
    
    public int Prime(int start, int end){ 
int i; //variable for determining prime numbers
int count=0;//variable for incrementing numbers between select numbers
int primeCount = 0;//amount of prime numbers
    for (count = start; count <=end; count++)//rolls through all my values between select numbers
{
    for (i=2;i<=count;i++)//increments my i count for testing prime
{
if (count%i==0)//checks prime
{
primeCount++; //increments primeCount to count amount of prime numbers
}
}
}
return primeCount;//returns primeCount value for input in main
    }
  }