时间转换工具类

package com.ryd.stocktrader.monitor.util;

import java.sql.Timestamp;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

/**
 * Created by Administrator on 2016/7/27.
 */
public class GetDayTime {
    //当天零点时间戳
    public static Long getDayBegin() {
        Calendar cal = Calendar.getInstance();
        cal.set(Calendar.HOUR_OF_DAY, 0);
        cal.set(Calendar.SECOND, 0);
        cal.set(Calendar.MINUTE, 0);
        cal.set(Calendar.MILLISECOND, 001);
        long time = new Timestamp(cal.getTimeInMillis()).getTime();
        return  time;
    }

    public static Long getDayEnd() {
       long time =  GetDayTime.getDayBegin() + 86400000;
       return  time;
    }
    //string 转 Unix时间戳
    public static Long stringToUnixT(String time){
        SimpleDateFormat simpleDateFormat =new SimpleDateFormat("yyyy-MM-dd");
        Date date= null;
        try {
            date = simpleDateFormat.parse(time);
        } catch (ParseException e) {
            e.printStackTrace();
        }
        long timeStemp = date.getTime();
        return timeStemp;
    }
    //string 转 Unix时间戳  (结束时间的24点)
    public static Long stringToUnixTEnd(String time){
        SimpleDateFormat simpleDateFormat =new SimpleDateFormat("yyyy-MM-dd");
        Date date= null;
        try {
            date = simpleDateFormat.parse(time);
        } catch (ParseException e) {
            e.printStackTrace();
        }
        long timeStemp = date.getTime() + 86400000;
        return timeStemp;
    }
    //当前日期
    public static String nowDay(){
        DateFormat d1 = DateFormat.getDateInstance();
        Date now = new Date();
        System.out.println(d1.format(now));
        return d1.format(now);
    }
    //一周前的日期
    public static String SevenDay(){
        Date date = new Date();
        int year=Integer.parseInt(new SimpleDateFormat("yyyy").format(date));
        int month=Integer.parseInt(new SimpleDateFormat("MM").format(date));
        int day=Integer.parseInt(new SimpleDateFormat("dd").format(date))-6;

        if(day<1){
            month-=1;
            if(month==0){
                year-=1;month=12;
            }
            if(month==4||month==6||month==9||month==11){
                day=30+day;
            }else if(month==1||month==3||month==5||month==7||month==8||month==10||month==12)
            {
                day=31+day;
            }else if(month==2){
                if(year%400==0||(year %4==0&&year%100!=0))day=29+day;
                else day=28+day;
            }
        }
        String y = year+"";String m ="";String d ="";
        if(month<10) m = "0"+month;
        else m=month+"";
        if(day<10) d = "0"+day;
        else d = day+"";

        return y+"-"+m+"-"+d;
    }
    //七天前的Unix时间戳
    public static long SevenDayToUnixT(){
        SimpleDateFormat simpleDateFormat =new SimpleDateFormat("yyyy-MM-dd");
        Date date= null;
        try {
            date = simpleDateFormat.parse(SevenDay());
        } catch (ParseException e) {
            e.printStackTrace();
        }
        long timeStemp = date.getTime();
        return timeStemp;
    }
    public static String lastMonth(){
        int allMonth = 1;       //allMonth为相差月份
        Date date = new Date();
        int year=Integer.parseInt(new SimpleDateFormat("yyyy").format(date));
        int month=Integer.parseInt(new SimpleDateFormat("MM").format(date))-allMonth;
        int day=Integer.parseInt(new SimpleDateFormat("dd").format(date));
        if(month <= 0){
            int yearFlag = (month*(-1))/12 + 1;
            int monthFlag = (month *(-1))%12;
            year -= yearFlag;
            month=monthFlag*(-1) +12;
        }
        else if(day>28){
            if(month==2){
                if(year%400==0||(year %4==0&&year%100!=0)){
                    day=29;
                }else day=28;
            }else if((month==4||month==6||month==9||month==11)&&day==31){
                day=30;
            }
        }
        String y = year+"";String m ="";String d ="";
        if(month<10) m = "0"+month;
        else m=month+"";
        if(day<10) d = "0"+day;
        else d = day+"";

        return y+"-"+m+"-"+d;
    }
    //当天11：30：00的时间戳  
    public static long cusTimeBefor(){
        SimpleDateFormat dateFormat=new SimpleDateFormat("yyyy-MM-dd");
        Date now=new Date();
        String dStr = dateFormat.format(now)+" 11:30:00";
        SimpleDateFormat dateFormat1=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        long time = 0;
        try {
            time = dateFormat1.parse(dStr).getTime();
        } catch (ParseException e) {
            e.printStackTrace();
        }
        return time;
    }
  //当天13：00：00的时间戳  
    public static long cusTimelast(){
        SimpleDateFormat dateFormat=new SimpleDateFormat("yyyy-MM-dd");
        Date now=new Date();
        String dStr = dateFormat.format(now)+" 13:00:00";
        SimpleDateFormat dateFormat1=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        long time = 0;
        try {
            time = dateFormat1.parse(dStr).getTime();
        } catch (ParseException e) {
            e.printStackTrace();
        }
        return time;
    }
    public static void main(String args []){
        System.out.println(lastMonth());
    }
}