在这个提示信息中,我怎么去识别用户是选择了"确定"和"取消"????

JOptionPane.showConfirmDialog(this,"要继续吗","提示信息",JOptionPane.OK_CANCEL_OPTION,JOptionPane.INFORMATION_MESSAGE );

import javax.swing.*;
import java.awt.event.*;

public class AA extends JFrame {
    Container c;
    int value;

    public AA() {
        super("aa");
        setSize(300, 200);
        c = getContentPane();
        c.setLayout(new BorderLayout());

        JButton b = new JButton("a");
        ActionListener action = new ActionListener() {
            public void actionPerformed(ActionEvent e) {

          value =JOptionPane.showConfirmDialog(c,"要继续吗","提示信息",JOptionPane.OK_CANCEL_OPTION,JOptionPane.INFORMATION_MESSAGE );
              if (value ==JOptionPane.OK_OPTION){
                    JOptionPane.showMessageDialog(c,"message1","message1",JOptionPane.YES_OPTION);
              }
                if(value ==JOptionPane.CANCEL_OPTION){
                   JOptionPane.showMessageDialog(c,"message2","message2",JOptionPane.YES_OPTION);
                }
            }
        };
        b.addActionListener(action);
        c.add(b, BorderLayout.CENTER);
        setVisible(true);
    }

    public static void main(String args[]) {
        AA a = new AA();
    }


}