java Date获取 年月日时分秒

package com.util;

  

import java.text.DateFormat;

import java.util.Calendar;

import java.util.Date;

  

  

public class Test {

    public void getTimeByDate(){

        Date date = new Date();

        DateFormat df1 = DateFormat.getDateInstance();//日期格式，精确到日

        System.out.println(df1.format(date));

        DateFormat df2 = DateFormat.getDateTimeInstance();//可以精确到时分秒

        System.out.println(df2.format(date));

        DateFormat df3 = DateFormat.getTimeInstance();//只显示出时分秒

        System.out.println(df3.format(date));

        DateFormat df4 = DateFormat.getDateTimeInstance(DateFormat.FULL,DateFormat.FULL); //显示日期，周，上下午，时间（精确到秒） 

        System.out.println(df4.format(date));  

        DateFormat df5 = DateFormat.getDateTimeInstance(DateFormat.LONG,DateFormat.LONG); //显示日期,上下午，时间（精确到秒） 

        System.out.println(df5.format(date));

        DateFormat df6 = DateFormat.getDateTimeInstance(DateFormat.SHORT,DateFormat.SHORT); //显示日期，上下午,时间（精确到分） 

        System.out.println(df6.format(date));

        DateFormat df7 = DateFormat.getDateTimeInstance(DateFormat.MEDIUM,DateFormat.MEDIUM); //显示日期，时间（精确到分）

        System.out.println(df7.format(date));

    }

    public void getTimeByCalendar(){

        Calendar cal = Calendar.getInstance();

        int year = cal.get(Calendar.YEAR);//获取年份

        int month=cal.get(Calendar.MONTH);//获取月份 

        int day=cal.get(Calendar.DATE);//获取日 

        int hour=cal.get(Calendar.HOUR);//小时 

        int minute=cal.get(Calendar.MINUTE);//分            

        int second=cal.get(Calendar.SECOND);//秒 

        int WeekOfYear = cal.get(Calendar.DAY_OF_WEEK);//一周的第几天

        System.out.println("现在的时间是：公元"+year+"年"+month+"月"+day+"日      "+hour+"时"+minute+"分"+second+"秒       星期"+WeekOfYear);

    }

    public static void main(String[] args) {

        Test t=new Test();

        t.getTimeByDate();

        System.out.println("****************************");

        t.getTimeByCalendar();

    }

}

　　

获取日，如果大于16则+2个月，否则+1个月，输出7个月

public static void main(String[] as) throws Exception {     int j;     Calendar cc = Calendar.getInstance();     int myYear = cc.get(Calendar.YEAR);      int myMonth = cc.get(Calendar.MONTH);     j=cc.get(Calendar.DATE)>16?3:2;     cc.set(Calendar.MONTH, myMonth+j);     System.out.println(myYear+"-"+cc.get(cc.MONTH));     for(int i=0;i<7;i++){         cc.add(cc.MONTH, 1);         int mm = cc.get(cc.MONTH);         int mmm=mm==0?12:mm;         System.out.println(myYear+"-"+mmm);     } }