A simple Java calendar program

/** The following is the code program for the calendar


has a question reply ycj@18e.net


**/


//calendertrain.java


package com.swing;


import java.awt.*;


import java.awt.event.*;


import javax.swing.*;


import java.util.*;


public class Calendertrain extends JFrame implements ActionListener {


JComboBox Month = new JComboBox (); Month Drop-down list box


JComboBox year = new JComboBox (); Year Drop-down list box


JLabel year_l = new JLabel ("Year::"); Define label


JLabel month_l = new JLabel ("Month::"); Define label


Date now_date = new Date (); Get today's date


jbutton[] Button_day = new jbutton[49]; Defines an array for storing dates


JButton BUTTON_OK = new JButton ("OK"); Realistic selection Date


JButton button_today = new JButton ("Today"); Show today's button


int now_year = now_date.getyear () + 1900; Get year value


int now_month = Now_date.getmonth (); Get month value (current month-1)


Boolean bool = false;


String year_int = null; Storage year


int month_int; Store month


JPanel pane_ym = new JPanel (); Place Drop-down list box and control button panel


JPanel pane_day = new JPanel (); Drop Date Panel


JPanel pane_parent = new JPanel (); Place above two panels


//Define method drawing panel


public Calendertrain () {


super ("calender!"); Set the panel to title


//---The following exercise to close the panel when the exit program


setdefaultcloseoperation (dispose_on_close);


Addwindowlistener (New Windowadapter () {


public void Windowclose (WindowEvent e) {


System.out.print ("CLOSING the WIN");


system.exit (0);


}


});


//---


setresizable (FALSE); The size of the panel cannot be changed


//Set Month


/* Year range is the current year's last 10 years to the current year of the next 20 years


* Month normal 1?? December


*/


for (int i = now_year-10 I <= now_year + i++) {


Year.additem (i + "");


}


for (int i = 1; i < i++) {


Month.additem (i + "");


}


Year.setselectedindex (10); Set year Drop-down list for current year


Pane_ym.add (year_l); Add year label


Pane_ym.add (year); Add year drop-down list box


Month.setselectedindex (Now_month); Set month Drop-down list for current month


Pane_ym.add (month_l); Add Month label


Pane_ym.add (Month); Add month drop-down list box


Pane_ym.add (BUTTON_OK); Add OK button


Pane_ym.add (Button_today); Add "Today" button


Button_ok.addactionlistener (this); OK button to add listener event


Button_today.addactionlistener (this); "Today" button to add a listener event


//month setting end


//Initialize Date button and draw


pane_day.setlayout (New GridLayout (7, 7, 10, 10));


for (int i = 0; i < i++) {


Button_day[i] = new JButton ("");


Pane_day.add (Button_day[i]);


}


This.setday (); Call the Setday () method


pane_parent.setlayout (New BorderLayout ()); Set Layout manager


Setcontentpane (Pane_day);


Setcontentpane (PANE_YM);


Pane_parent.add (Pane_day, Borderlayout.south);


Pane_parent.add (Pane_ym, Borderlayout.north);


Setcontentpane (pane_parent);


pack ();


Show ();


}


void Setday () {


if (bool) {


Year_int = Now_year + "";


month_int = Now_month;


} else {


year_int = Year.getselecteditem (). toString ();


month_int = Month.getselectedindex ();


}


int year_sel = Integer.parseint (year_int)-1900; Get year value


Date dt = new Date (Year_sel, Month_int, 1); Construct a date


GregorianCalendar cal = new GregorianCalendar (); Create a Calendar instance


cal.settime (DT);


String week[] = {"Sun", "Mon", "Tue", "Wed", "Thur", "Fri", "Sat"};


int day = 0; Days in which a month is stored


int day_week = 0; The number that is used to store the first day of the month is the
of the week.

//--adds the week to the top 7 buttons


for (int i = 0; i < 7; i++) {


Button_day[i].settext (Week[i]);


}


//--


/* Judgment is a few months, according to which you set day's value


* One of the February to determine whether it is a leap year


*/


if (month_int = 0


|| Month_int = 2


|| Month_int = 4


|| Month_int = 6


|| Month_int = 7


|| Month_int = 9


|| Month_int = = 11) {


day = 31;


} else if (


Month_int = = 3


|| Month_int = 5


|| Month_int = 8


|| Month_int = = 10) {


Day = 30;


} else {


if (Cal.isleapyear (Year_sel)) {


day = 29;


} else {


day = 28;


}


}


Day_week = 7 + dt.getday ();


int count = 1;


/* Draw button


* Here we first want to determine the starting position of the button by the first day of the month selected


* Where Day_week is the starting position we want to draw


* Empty
for buttons that don't have a value to display

*/


for (int i = Day_week i < Day_week + day; count++, i++) {


if (i% 7 = 0


|| i = = 13


|| i = = 20


|| i = = 27


|| i = = 48


|| i = = 34


|| i = = 41) {


if (i = = Day_week + now_date.getdate ()-1) {


Button_day[i].setforeground (Color.Blue);


Button_day[i].settext (Count + "");


} else {


Button_day[i].setforeground (color.red);


Button_day[i].settext (Count + "");


}


} else {


if (i = = Day_week + now_date.getdate ()-1) {


Button_day[i].setforeground (Color.Blue);


Button_day[i].settext (Count + "");


} else {


Button_day[i].setforeground (Color.Black);


Button_day[i].settext (Count + "");


}


}


}


//--for a button that has no date value display


if (Day_week = = 0) {


for (int i = day; I < i++) {


Button_day[i].settext ("");


}


} else {


//First day front button to empty


for (int i = 7; i < Day_week; i++) {


Button_day[i].settext ("");


}//The button behind the last day to empty


for (int i = Day_week + day; i < i++) {


Button_day[i].settext ("");


}


}


}


public void actionperformed (ActionEvent e) {


if (e.getsource () = = BUTTON_OK) {


bool = false;


This.setday (); If you click the OK button, call Setday () to redraw the button


} else if (E.getsource () = Button_today) {


bool = true;


Year.setselectedindex (10);


Month.setselectedindex (Now_month);


This.setday (); If you click Today's button, get today's date


}


}


public static void Main (string[] args) {


Calendertrain ct = new Calendertrain ();


}


}