完整的java输入日期显示j日历源代码

//输入 日期 知道星期几
import javax.swing.JOptionPane; //装载JOptionPane类
public class A4_26 {
public static void main(String[] args)
{
String s1, s2,s3;
s1 = JOptionPane.showInputDialog("请输入年：");
// s1接收来自输入文本框的年
s2 = JOptionPane.showInputDialog("请输入月：");
// s2接收来自输入文本框的月
s3 = JOptionPane.showInputDialog("请输入日");
// s3接收来自输入文本框的日
int firstNumber, secondNumber,thirdNumber;
firstNumber = Integer.parseInt(s1);
// 将字符串s1转换成整数赋值给firstNumber
secondNumber = Integer.parseInt(s2);
// 将字符串s2转换成整数赋值给secondNumber
thirdNumber = Integer.parseInt(s3);

int sum=0;
/****************************************************/
for(int year=1900;year<=firstNumber-1;year++)
{
if(year%4==0&&year%100!=0||year%400==0)
{
sum+=366;
}
else
{sum+=365;}
}
/****************************************************/
for(int month=1;month<=secondNumber-1;month++) //在此输入多少 月-1
{
if(month==2)
{
if(firstNumber%4==0&&firstNumber%100!=0||firstNumber%400==0)
{

sum+=29;
}
else
{sum+=28;}
}
else
{
if(month==4||month==6||month==9||month==11){

sum+=30;
}
else
{
sum+=31;}
}
}
/****************************************************/
int days=0;
for(int month=1;month<=secondNumber-1;month++) //在此输入多少 月-1
{
if(month==2)
{
if(firstNumber%4==0&&firstNumber%100!=0||firstNumber%400==0)
{
days=29;

}
else
{days=28;}
}
else
{
if(month==4||month==6||month==9||month==11){
days=30;
}
else
{days=31;}
}
}
sum=sum+thirdNumber;
/****************************************************/
int savesum=0;
savesum=sum;
sum=sum-thirdNumber+1;
int weekday=sum%7;
System.out.println("日\t一\t二\t三\t四\t五\t六");
for(int i=0;i<=weekday-1;i++)
{
System.out.print("\t");
}

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

{

if(sum%7==6){
System.out.print(i+"\n");
}
else{
System.out.print(i+"\t");
}
sum++;
}

sum=savesum;
System.out.print("\n");
System.out.print("\n");
System.out.println("1900年1月1日到" +
""+firstNumber +"年"+
secondNumber +"月"+
thirdNumber +"日"+
+sum+"天");
sum=sum%7;
System.out.println( "这一天是星期 "+sum+"");
JOptionPane.showMessageDialog(null, firstNumber + "年"
+ secondNumber + "月"
+ thirdNumber + "日，是星期"
+ sum );

}
}