17.17

import java.awt.*;
import java.util.Calendar;
import java.util.GregorianCalendar;
import javax.swing.*;
import javax.swing.border.LineBorder;

public class Test_17_17 extends JFrame{
    private CanlendarPanel calDer = new CanlendarPanel();
    private JPanel JPholder = new JPanel();
    private JLabel jl[] = { new JLabel("Sunday"),new JLabel("Monday"),new JLabel("Tuesday"),new JLabel("Wednesday"),new JLabel("Wednesday"),new JLabel("Thursday"),
            new JLabel("Friday"),new JLabel("Saturday")    };
    
    public Test_17_17(){
        for(int i = 0; i < 7 ; i++)
            jl[i].setBorder(new LineBorder(Color.black,1));
        JPholder.setLayout(new GridLayout(1,7));
        for(int i = 0; i < 7 ; i++)
            JPholder.add(jl[i]);
        add(new JPanel().add(new Label(calDer.Year+"/"+calDer.Month)),BorderLayout.NORTH);
        add(JPholder,BorderLayout.CENTER);
        add(calDer,BorderLayout.SOUTH);        
    }
    public static void main(String[] args) {
        // TODO Auto-generated method stubs
        Test_17_17 frame = new Test_17_17();
        frame.setTitle("Test_17_17");
        frame.setSize(400,200);
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);        
    }
    
    class CanlendarPanel extends JPanel{
        private Calendar G = new GregorianCalendar();
        private int Year = G.get(Calendar.YEAR);
        private int Month = G.get(Calendar.MONTH);
        private int Days_of_Month = G.getActualMaximum(Calendar.DATE);        
        private int Day_of_Week = G.get(Calendar.DAY_OF_WEEK);
        
        public CanlendarPanel(){
            //draw the month calendar
            setLayout(new GridLayout(G.getActualMaximum(Calendar.WEEK_OF_MONTH),7));
            //把G当前的天设置为1号
            G.set(Calendar.DATE,1);
            System.out.println("第一天是星期几"+ G.get(Calendar.DAY_OF_WEEK));
            for(int i = 1 , j = 1; i <= G.getActualMaximum(Calendar.WEEK_OF_MONTH) * 7; i++)
            {                
                if(i < G.get(Calendar.DAY_OF_WEEK)) add(new JLabel());
                else if(i <= Days_of_Month) {
                JLabel jlTemp = new JLabel(j +"");                
                jlTemp.setBorder(new LineBorder(Color.BLACK,1));
                add(jlTemp); 
                j++;
                }
                else add(new JLabel());                
            }            
        }
    }
}