/**
* Test user input for prime p & q and public exponent e.
*
* @param p Prime p.
* @param q Prime q.
* @param e Public exponent.
* @return boolean True, if input is ok.
*/
public boolean testInputEligibility(BigInteger p, BigInteger q, BigInteger e) {
TestPrimality primeTester = new TestPrimality();
if (!(primeTester.isPrime(p))) {
return false;
}
if (!(primeTester.isPrime(q))) {
return false;
}
if (p.equals(q)) {
return false;
}
if (!(e.intValue() > 1)) {
return false;
}
BigInteger phi = p.subtract(BigInteger.ONE).multiply(q.subtract(BigInteger.ONE));
if (!(phi.gcd(e).intValue() == 1)) {
return false;
}
return true;
}
/**
* Shows an error dialog if p, q or e is not suitable.
*
* @param frame
* @param p Prime p.
* @param q Prime q.
* @param e Public exponent.
*/
public void showInputError(JFrame frame, BigInteger p, BigInteger q, BigInteger e) {
TestPrimality primeTester = new TestPrimality();
BigInteger phi = p.subtract(BigInteger.ONE).multiply(q.subtract(BigInteger.ONE));
if (!(primeTester.isPrime(p))) {
JOptionPane.showMessageDialog(
frame, "P is not a prime.", "Input error", JOptionPane.ERROR_MESSAGE);
} else if (!(primeTester.isPrime(q))) {
JOptionPane.showMessageDialog(
frame, "Q is not a prime.", "Input error", JOptionPane.ERROR_MESSAGE);
} else if (p.equals(q)) {
JOptionPane.showMessageDialog(
frame, "P and Q should not be equal.", "Input error", JOptionPane.ERROR_MESSAGE);
} else if (!(e.intValue() > 1)) {
JOptionPane.showMessageDialog(
frame, "E must be greater than 1.", "Input error", JOptionPane.ERROR_MESSAGE);
} else if (!(phi.gcd(e).intValue() == 1)) {
JOptionPane.showMessageDialog(
frame,
"E not suitable. gcd(e, (p-1)(q-1)) must equal one .",
"Input error",
JOptionPane.ERROR_MESSAGE);
}
}