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);

}

}