isAPrime.java

import java.util.*;
public class isAPrime
{
    Scanner scan = new Scanner(System.in);
    public isAPrime(){
        
        System.out.println("Enter a number to test if its prime");
      class variables  
      int y = scan.nextInt();
        int count = 2;
        int test;
        
        //int max = 100;
        //int min = 2;
        //int y = (int)(Math.random() * ((max - min) + 1)) + min;//inclusive
        //System.out.println("Number = " + y);
        boolean prime = isPrime(y);
        System.out.println(prime);
        System.out.println("All primes under 100:");
        while(count <= 100){//test every number under 100 for primeness
            test = allPrime(count);
            if(test == 1){
                System.out.print(count + " ");
            }
            count ++;
        }
        
        
    }
    public boolean isPrime(int y)
    {//test user inputted number 
        int compare = 2;
        int remainder = 0;
        boolean prime = false;
        while(compare < y){
            remainder = y%compare;
            if(remainder == 0){
                compare = y;
            }else if (compare == (y-1)){
                prime = true;
            }
            compare ++;
        }
        return prime;
    }
    public int allPrime(int x){//test all numbers
        int compare = 2;
        int remainder = 0;
        int yes = 0;
        while(compare < x){
            remainder = x%compare;
            if(remainder == 0){
                compare = x;
            }else if (compare == (x-1)){
                yes = 1;
            }
            compare ++;
        }
        return yes;
    }
}