自己写的一个小小日历。执行程序是柯自己主动定位到当前年月日，当点击下个月button是会定位到下个月的这一天，就是说天数不会变。当在一个月中点击某一天时，以下的时间也会随时变化。
import java.util.Calendar;
public class CalendarMainClass {
public static void main(String args[]) {
CalendarFrame frame=new CalendarFrame();
frame.setBounds(100,100,360,300);
frame.setVisible(true);
frame. setYearAndMonth((Calendar.getInstance()).get(Calendar.YEAR),(Calendar.getInstance()).get(Calendar.MONTH)+1);
}
}
import java.util.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
public class CalendarFrame extends JFrame implements ActionListener, MouseListener{
/**
*
*/
private static final long serialVersionUID = 1L;
JLabel labelDay[]=new JLabel[42];
JButton titleName[]=new JButton[7];
JLabel labelCom=new JLabel();//跟踪选中的日期
String name[]={"日","一","二","三", "四","五","六"};
JButton nextMonth,previousMonth;
CalendarBean calendar;
JLabel showMessage=new JLabel("",JLabel.CENTER);
int year=2011,month=2;
public CalendarFrame() {
JPanel pCenter=new JPanel();
pCenter.setBackground(Color.white);
pCenter.setLayout(new GridLayout(7,7)); //将pCenter的布局设置为7行7列的GridLayout 布局。
for(int i=0;i<7;i++) {
titleName[i]=new JButton(name[i]);
titleName[i].setBorder(new SoftBevelBorder(BevelBorder.RAISED));
pCenter.add(titleName[i]);
}
for(int i=0;i<42;i++) {
labelDay[i]=new JLabel("",JLabel.CENTER);
//labelDay[i].setBorder(new EtchedBorder(EtchedBorder.RAISED));
labelDay[i].setBorder(BorderFactory.createLineBorder (Color.orange, 1));
pCenter.add(labelDay[i]);//pCenter加入组件labelDay[i]。
}
calendar=new CalendarBean();
nextMonth=new JButton("下月");
previousMonth=new JButton("上月");
nextMonth.addActionListener(this);
previousMonth.addActionListener(this);
JPanel pNorth=new JPanel(),
pSouth=new JPanel();
pCenter.setBackground(Color.white);
pNorth.setBackground(Color.white);
pSouth.setBackground(Color.white);
pNorth.add(previousMonth);
pNorth.add(nextMonth);
pSouth.add(showMessage);
add(pCenter,BorderLayout.CENTER);
add(pNorth,BorderLayout.NORTH); // 窗体加入pNorth 在北面区域
add(pSouth ,BorderLayout.SOUTH); // 窗体加入pSouth 在南区域。
//setYearAndMonth(year,month);
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
}
public void setYearAndMonth(int y,int m) {
year=y;
month=m;
calendar.setYear(y);
calendar.setMonth(m);
calendar.setDay((Calendar.getInstance()).get(Calendar.DAY_OF_MONTH));
String day[]=calendar.getCalendar();
for(int i=0;i<42;i++)
{
labelDay[i].setText(day[i]);
labelDay[i].addMouseListener(this);//对每一个标签监听
if(day[i]!=null&&day[i].equals(String.valueOf(calendar.getDay())))//系统日期为黄色
{
labelDay[i].setOpaque(true); // 标签设置不透明才干设置颜色
labelDay[i].setBackground(Color.orange);
labelCom= labelDay[i];//点亮的标签
}
}
showMessage.setText("日历："+calendar.getYear()+"年"+ calendar.getMonth()+"月"+ calendar.getDay()+"日");
}
public void actionPerformed(ActionEvent e) {
if(e.getSource()==nextMonth) {
month=month+1;
if(month>12)
{
month=1;
year=year+1;
}
calendar.setMonth(month);
calendar.setYear(year);
String day[]=calendar.getCalendar();
for(int i=0;i<42;i++) {
labelDay[i].setOpaque(false);
}
for(int i=0;i<42;i++) {
labelDay[i].setText(day[i]);
labelDay[i].addMouseListener(this);
if(day[i]!=null&&day[i].equals(String.valueOf(calendar.getDay())))
{
labelDay[i].setOpaque(true);
labelDay[i].setBackground(Color.orange);
labelCom= labelDay[i];
}
}
}
else if(e.getSource()==previousMonth) {
month=month-1;
if(month<1)
{
month=12;
year=year-1;
}
calendar.setMonth(month);
calendar.setYear(year);
String day[]=calendar.getCalendar();
for(int i=0;i<42;i++) {
labelDay[i].setOpaque(false);
}
for(int i=0;i<42;i++)
{
labelDay[i].setText(day[i]);
labelDay[i].addMouseListener(this);
if(day[i]!=null&&day[i].equals(String.valueOf(calendar.getDay())))
{
labelDay[i].setOpaque(true);
labelDay[i].setBackground(Color.orange);
labelCom= labelDay[i];
}
}
}
showMessage.setText("日历："+calendar.getYear()+"年"+ calendar.getMonth()+"月"+ calendar.getDay()+"日");
}
@Override
public void mouseClicked(MouseEvent e) {
// TODO Auto-generated method stub
}
@Override
public void mousePressed(MouseEvent e) {
JLabel i=(JLabel)e.getSource();
if(i.getText()!=null)
{
labelCom.setOpaque(false);
i.setOpaque(true);
i.setBackground(Color.orange);
showMessage.setText("日历："+calendar.getYear()+"年"+ calendar.getMonth()+"月"+Integer.parseInt(i.getText())+"日");
labelCom=i;
//刷新界面
for(int j=0;j<42;j++)
{
labelDay[j].repaint();
}
}
}
@Override
public void mouseReleased(MouseEvent e) {
// TODO Auto-generated method stub
}
@Override
public void mouseEntered(MouseEvent e) {
// TODO Auto-generated method stub
}
@Override
public void mouseExited(MouseEvent e) {
// TODO Auto-generated method stub
}
}
import java.util.Calendar;
public class CalendarBean {
String day[];
int year=2005,month=0;
int DDay=0;
public void setYear(int year) {
this.year=year;
}
public int getYear() {
return year;
}
public void setMonth(int month) {
this.month=month;
}
public int getMonth() {
return month;
}
public void setDay(int DDay) {
this.DDay=DDay;
}
public int getDay() {
return DDay;
}
public String[] getCalendar() {
String a[]=new String[42];
Calendar 日历=Calendar.getInstance();//获得系统时间
日历.set(year,month-1,1); //设置指定时间
int 星期几=日历.get(Calendar.DAY_OF_WEEK)-1;
int day=0;
if(month==1||month==3||month==5||month==7||month==8||month==10||month==12)
day=31;
if(month==4||month==6||month==9||month==11)
day=30;
if(month==2) {
if(((year%4==0)&&(year%100!=0))||(year%400==0))
day=29;
else
day=28;
}
for(int i=星期几,n=1;i<星期几+day;i++) {
a[i]=String.valueOf(n) ;
n++;
}
return a;
}
} 
