java中时间的练习

package Demo;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class 时间 {
    public static void main(String[] args) {
        //得到当前年月
        Calendar now = Calendar.getInstance();
        int year = now.get(Calendar.YEAR);
        int month = now.get(Calendar.MONTH)+1;
        int day = now.get(Calendar.DATE);
        System.out.println(year+"年"+month+"月"+day+"日");
        //得到当前时间
        Date date = new Date();
        System.out.println(date);
        //设置时间格式得到时间
        SimpleDateFormat sf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        System.out.println(sf.format(date));
    }
}