[prg] Prime Number Generator

/*
 * Prime Numbers
 * @author Maximilian Krause
 * @since 11-06-2015
 * @ver 1.1.1
 *
 * This script is capable of finding the prime numbers between two specific numbers.
 *
 * Changelog
 * ---------
 * v1.1
 * @since 11-06-2015
 * - Added feature to remove the last comma through a substring.
 *
 * v1.1.1
 * @since 11-06-2015
 * - Fixed too early printing of the number 2.
 *
 * Licensed under CC BY 4.0.
 *
 * TODO: Add multi-threading
 */

package de.maxkrause;
import java.util.*;

public class main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        System.out.print("Which number should be checked first? ");
        int firstCheck = scan.nextInt();
        System.out.print("Which number should be checked last? ");
        int lastCheck = scan.nextInt();
        scan.close();
        System.out.println("Job starting. Please wait...");
        String output = "";
        if(firstCheck < 3){
            firstCheck = 3;
        }
        for(int i = firstCheck; i <= lastCheck; i++){
            boolean isPrime = true;
            for(int j = i-1; j > 0; j--){
                if(j != 0 && j != 1){
                    if(i % j == 0){
                        isPrime = false;
                    }
                }
            }
            if(isPrime){
                output += i + ", ";
            }
        }
        if(!(firstCheck > 2)){
            System.out.print("2, ");
        }
        System.out.println(output.substring(0, output.length()-2));
        System.out.println("Job completed.");
    }
}