网上信息发布平台 java+ssh+jsp+sql

package com.aptech.jb.util; import java.util.Date; import java.util.Scanner; import java.text.SimpleDateFormat; public class DateUtil { /** * 给定一个小于30的数，返回向后退该天后的日期 * * @param backDay * @return */ public String getBackDate(int backDay) { String today = new SimpleDateFormat("yyyy-MM-dd").format(new Date()); String date = ""; int year = Integer.parseInt((today.split("-"))[0]); int month = Integer.parseInt((today.split("-"))[1]); int day = Integer.parseInt((today.split("-"))[2]); if (day - (backDay - 1) > 0) { return date + year + "-" + month + "-" + (day - (backDay - 1)); } else { return date + getBackYear(year, month) + "-" + getLastMonth(month) + "-" + (getMonthDays(year, getLastMonth(month)) - (backDay - 1 - day)); } } /** * 给定一个小于30的数，返回向前推进该天后的日期 * * @param forwardDay * @return */ public String getForwardDate(int forwardDay) { String today = new SimpleDateFormat("yyyy-MM-dd").format(new Date()); int year = Integer.parseInt((today.split("-"))[0]); int month = Integer.parseInt((today.split("-"))[1]); int day = Integer.parseInt((today.split("-"))[2]); if (day + forwardDay <= 28) { return "" + year + "-" + month + "-" + (day + forwardDay); } else { switch (month) { case 2: return "" + getForwardYear(year, month) + "-" + getNextMonth(month) + "-" + (forwardDay - (getMonthDays(year, month) - day)); case 4: if (day + forwardDay <= 30) { return "" + year + "-" + month + "-" + (day + forwardDay); } else { return "" + getForwardYear(year, month) + "-" + getNextMonth(month) + "-" + (forwardDay - (getMonthDays(year, month) - day)); } case 6: if (day + forwardDay <= 30) { return "" + year + "-" + month + "-" + (day + forwardDay); } else { return "" + getForwardYear(year, month) + "-" + getNextMonth(month) + "-" + (forwardDay - (getMonthDays(year, month) - day)); } case 9: if (day + forwardDay <= 30) { return "" + year + "-" + month + "-" + (day + forwardDay); } else { return "" + getForwardYear(year, month) + "-" + getNextMonth(month) + "-" + (forwardDay - (getMonthDays(year, month) - day)); } case 11: if (day + forwardDay <= 30) { return "" + year + "-" + month + "-" + (day + forwardDay); } else { return "" + getForwardYear(year, month) + "-" + getNextMonth(month) + "-" + (forwardDay - (getMonthDays(year, month) - day)); } default: if (day + forwardDay <= 31) { return "" + year + "-" + month + "-" + (day + forwardDay); } else { return "" + getForwardYear(year, month) + "-" + getNextMonth(month) + "-" + (forwardDay - (getMonthDays(year, month) - day)); } } } } /** * 制定年,给出是否闰年 * * @param year * @return */ public boolean isRn(int year) { if (year % 4 == 0 && !(year % 100 == 0 && year % 400 != 0)) return true; return false; } /** * 给定月,返回下一个月的月份 * * @param month * @return */ public int getLastMonth(int month) { if (month != 1) return month - 1; else return 12; } /** * 给定月,返回上一个月的月份 * * @param month * @return */ public int getNextMonth(int month) { if (month != 12) return month + 1; else return 1; } /** * 指定年和月,给出上一个月的年份 * * @param year * @param month * @return */ public int getBackYear(int year, int month) { if (getLastMonth(month) == 12) return year - 1; else return year; } /** * 指定年和月,给出下一个月的年份 * * @param year * @param month * @return */ public int getForwardYear(int year, int month) { if (getNextMonth(month) == 1) return year + 1; else return year; } /** * 制定年和月,给出该月天数 * * @param year * @param month * @return */ public int getMonthDays(int year, int month) { int lastMonthDays = 0; switch (month) { case 2: if (isRn(year)) lastMonthDays = 28; else lastMonthDays = 29; break; case 4: lastMonthDays = 30; break; case 6: lastMonthDays = 30; break; case 9: lastMonthDays = 30; break; case 11: lastMonthDays = 30; break; default: lastMonthDays = 31; } return lastMonthDays; } // private int d = 0 ; // public int geDay(int year,int month,int backDay){ // if (getMonthDays(year,month) - (backDay - 1) > 0) { // d = getMonthDays(year,month) - (backDay - 1); // return d; // }else{ // geDay(year,month,backDay); // // } // return d; // } public static void main(String[] args) { DateUtil du = new DateUtil(); // for (int m = 1; m <= 12; m++) { // System.out.println("1900年" + m + "月的天数" + du.getMonthDays(1900, m)); // } int sign = 1; Scanner sc = new Scanner(System.in); while (sign != 0) { System.out.print("输入一个天数:"); sign = sc.nextInt(); System.out.println(du.getForwardDate(sign)); } System.out.println("程序退出"); } }