package leapyear;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class leapyear extends JFrame implements ActionListener{
        private JTextField textField=null;
        private JButton btn;
        
        public  leapyear(){
        JFrame f = new JFrame("闰年");
        JPanel p = new JPanel();
        textField = new JTextField("",10);
        JButton btn = new JButton("确定");
        JLabel label1 = new JLabel("输入");
        
        btn.addActionListener(this);    
        p.add(label1);
        p.add(textField);
        p.add(btn);
        f.add(p);
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setSize(300, 200); 
        f.setBounds(150,150,150,150);
        f.pack();
        }
        public void actionPerformed (ActionEvent e){
            String f;
            f =textField.getText();    
            String q="";
            try{
                int p1 = Integer.parseInt(f);
                if(checkleap(p1)){
                     q="该年份是闰年!";
                  }
                else{
                     q="该年份不是闰年!";
                }
            }
            catch (NumberFormatException s) {
            
                q="非法输入!";
            } 
            textField.setText(q);
        }
        public Boolean checkleap(int year)
        {
            Boolean temp = false;
            if (year % 4 == 0)
            {
                temp = true;
            }
            if (year % 100 == 0)
            {
                temp = false;
            }
            if (year % 400 == 0)
            {
                temp = true;
            }
            return temp;
        }
         public static void main(String[] args) {
                new leapyear();
            }
    
}