How do I solve this program? The program is to find the prime factors of a number. The answer I keep getting is 0. If you need the directions respond.

Question

import javax.swing.JOptionPane;

public class FactorGeneratorTest

{

public static void main(String[] args)

{

String input =JOptionPane.showInputDialog("Enter a positive number, (cancel to quit)");

int inputNumber = Integer.parseInt(input);

FactorGenerator generator = new FactorGenerator();

if (input == null)

{

System.out.println("You just quit.");

System.exit(0);

}else

{

System.out.println("Factors of " + inputNumber + ": " + generator.getFactor());

}

}

}

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

public class FactorGenerator

{

public FactorGenerator()

{

}

private int number; private int factor; //instance fields

public void nextFactor(int someNum) //grabs next factor

{

someNum = number;

for(int i = 2; i <= number; i++) //initial prime number counting to input

{

if(number % i == 0)

{

i = factor;

}

}

}

public int getFactor()

{

return factor;

}

public boolean hasMoreFactors() //(predicate method) allows factors to separate from non-prime factors

{

boolean hasMoreFactors = false;

if (number >= 2)

{

return true;

} else

{

return false;

}

}

}

Answer 1

I would use recursion... here's the code

//*********************************************************************************/

class PrimeFactors

{

private long longIntNum;

public PrimeFactors( long L)

{

longIntNum = L;

}

public void Go ( long L)

{

boolean factor_found = false;

int i=2;

// looks for a prime factor between 2 and half the number

for (i=2; i<L/2+1; i++)

{

if ((L % i)==0) // found one !!! prints it and bails

{

System.out.println(i + " is a prime factor ");

factor_found=true;

break;

}

}

if (factor_found) // prime factor was found at loop counter i

{

L = L/i; // factors it out and repeats the process

Go(L);

}

else // we're done: there aren't any more factors

{

System.out.println( L + " is a prime factor ");

}

}

public static void main( String args[])

{

if (args.length>0) // passes the input number of the command line

{

long longIntNum = Long.parseLong(args[0]);

if (longIntNum<0) //peels off the negative if neccesary

{

longIntNum = -1*longIntNum;

System.out.println(" -1 is a factor ");

}

PrimeFactors myPrimeFactors = new PrimeFactors(longIntNum);

myPrimeFactors.Go(longIntNum);

}

else

{

System.out.println(" Please pass the number on the command line:");

System.out.println(" java PrimeFactors longIntNum ");

}

}