Can I use IF statements with a message dialog in java? [on hold]

So, I've been stumped on this piece of code for about a week now, I want to have the code sending an error message when the user chooses 'No' or 'Cancel' and I've looked everywhere for a solution for this! Can anybody help?

int mc = JOptionPane.QUESTION_MESSAGE;

int bc = JOptionPane.YES_NO_CANCEL_OPTION;

int ch = JOptionPane.showConfirmDialog (null, "Do you accept the rules?",
"Rules";

if (bc = NO)
{
     JOptionPane.showInputDialog("Sorry, you cannot continue without agreeing to the rules.");
}
else if
{
     JOptionPane.showInputDialog("Sorry, you cannot continue without agreeing to the rules.");
}
else
{
    JOptionPane.showInputDialog("Thank you, you may continue!");
}