Java 获取指定日期的方法汇总

import java.text.DateFormat;
import java.text.ParsePosition;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

import org.junit.Test;

public class TimeUtil {
// 用来全局控制 上一周，本周，下一周的周数变化
private int weeks = 0;
// 一月最大天数
private int MaxDate;
// 一年最大天数
private int MaxYear;/**
* 得到指定月后（前）的日期 参数传负数即可
*
*/
public static String getAfterMonth(int month) {
Calendar c = Calendar.getInstance();// 获得一个日历的实例
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = sdf.parse("2009-11-04");// 初始日期
} catch (Exception e) {

}
c.setTime(date);// 设置日历时间
c.add(Calendar.MONTH, month);// 在日历的月份上增加6个月
String strDate = sdf.format(c.getTime());// 的到你想要得6个月后的日期
return strDate;

}

/**
* 得到二个日期间的间隔天数
*/
public static String getTwoDay(String sj1, String sj2) {
SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
long day = 0;
try {
java.util.Date date = myFormatter.parse(sj1);
java.util.Date mydate = myFormatter.parse(sj2);
day = (date.getTime() - mydate.getTime()) / (24 * 60 * 60 * 1000);
} catch (Exception e) {
return "";
}
return day + "";
}

/**
* 根据一个日期，返回是星期几的字符串
*/
public static String getWeek(String sdate) {
// 再转换为时间
Date date = TimeUtil.strToDate(sdate);
Calendar c = Calendar.getInstance();
c.setTime(date);
// int hour=c.get(Calendar.DAY_OF_WEEK);
// hour 中存的就是星期几了，其范围 1~7
// 1=星期日 7=星期六，其他类推
return new SimpleDateFormat("EEEE").format(c.getTime());
}

/**
* 将短时间格式字符串转换为时间 yyyy-MM-dd
*/
public static Date strToDate(String strDate) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
ParsePosition pos = new ParsePosition(0);
Date strtodate = formatter.parse(strDate, pos);
return strtodate;
}

/**
* 两个时间之间的天数
*
* @param date1
* @param date2
* @return
*/
public static long getDays(String date1, String date2) {
if (date1 == null || date1.equals(""))
return 0;
if (date2 == null || date2.equals(""))
return 0;
// 转换为标准时间
SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
java.util.Date date = null;
java.util.Date mydate = null;
try {
date = myFormatter.parse(date1);
mydate = myFormatter.parse(date2);
} catch (Exception e) {
}
long day = (date.getTime() - mydate.getTime()) / (24 * 60 * 60 * 1000);
return day;
}

/**
* 计算当月最后一天,返回字符串
*/
public String getDefaultDay() {
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar lastDate = Calendar.getInstance();
lastDate.set(Calendar.DATE, 1);// 设为当前月的1 号
lastDate.add(Calendar.MONTH, 1);// 加一个月，变为下月的1 号
lastDate.add(Calendar.DATE, -1);// 减去一天，变为当月最后一天
str = sdf.format(lastDate.getTime());
return str;
}

/**
* 上月第一天
*/
public String getPreviousMonthFirst() {
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar lastDate = Calendar.getInstance();
lastDate.set(Calendar.DATE, 1);// 设为当前月的1 号
lastDate.add(Calendar.MONTH, -1);// 减一个月，变为下月的1 号
// lastDate.add(Calendar.DATE,-1);//减去一天，变为当月最后一天
str = sdf.format(lastDate.getTime());
return str;
}

/**
* 获取当月第一天
*/
public String getFirstDayOfMonth() {
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar lastDate = Calendar.getInstance();
lastDate.set(Calendar.DATE, 1);// 设为当前月的1 号
str = sdf.format(lastDate.getTime());
return str;
}

/**
* 获得本周星期日的日期
*/
public String getCurrentWeekday() {
weeks = 0;
int mondayPlus = this.getMondayPlus();
GregorianCalendar currentDate = new GregorianCalendar();
currentDate.add(GregorianCalendar.DATE, mondayPlus + 6);
Date monday = currentDate.getTime();
DateFormat df = DateFormat.getDateInstance();
String preMonday = df.format(monday);
return preMonday;
}

/**
* 获取当天时间
*/
public String getNowTime(String dateformat) {
Date now = new Date();
SimpleDateFormat dateFormat = new SimpleDateFormat(dateformat);// 可以方便地修改日期格式
String hehe = dateFormat.format(now);
return hehe;
}

/**
* 获得当前日期与本周日相差的天数
*/
private int getMondayPlus() {
Calendar cd = Calendar.getInstance();
// 获得今天是一周的第几天，星期日是第一天，星期二是第二天......
int dayOfWeek = cd.get(Calendar.DAY_OF_WEEK) - 1; // 因为按中国礼拜一作为第一天所以这里减1
if (dayOfWeek == 1) {
return 0;
} else {
return 1 - dayOfWeek;
}
}

/**
* 获得本周一的日期
*/
public String getMondayOFWeek() {
weeks = 0;
int mondayPlus = this.getMondayPlus();
GregorianCalendar currentDate = new GregorianCalendar();
currentDate.add(GregorianCalendar.DATE, mondayPlus);
Date monday = currentDate.getTime();
DateFormat df = DateFormat.getDateInstance();
String preMonday = df.format(monday);
return preMonday;
}

/**
* 获得相应周的周六的日期
*/
public String getSaturday() {
int mondayPlus = this.getMondayPlus();
GregorianCalendar currentDate = new GregorianCalendar();
currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 * weeks + 6);
Date monday = currentDate.getTime();
DateFormat df = DateFormat.getDateInstance();
String preMonday = df.format(monday);
return preMonday;
}

/**
* 获得上周星期日的日期
*/
public String getPreviousWeekSunday() {
weeks = 0;
weeks--;
int mondayPlus = this.getMondayPlus();
GregorianCalendar currentDate = new GregorianCalendar();
currentDate.add(GregorianCalendar.DATE, mondayPlus + weeks);
Date monday = currentDate.getTime();
DateFormat df = DateFormat.getDateInstance();
String preMonday = df.format(monday);
return preMonday;
}

/**
* 获得上周星期一的日期
*/
public String getPreviousWeekday() {
weeks--;
int mondayPlus = this.getMondayPlus();
GregorianCalendar currentDate = new GregorianCalendar();
currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 * weeks);
Date monday = currentDate.getTime();
DateFormat df = DateFormat.getDateInstance();
String preMonday = df.format(monday);
return preMonday;
}

/**
* 获得下周星期一的日期
*/
public String getNextMonday() {
weeks++;
int mondayPlus = this.getMondayPlus();
GregorianCalendar currentDate = new GregorianCalendar();
currentDate.add(GregorianCalendar.DATE, mondayPlus + 7);
Date monday = currentDate.getTime();
DateFormat df = DateFormat.getDateInstance();
String preMonday = df.format(monday);
return preMonday;
}

/**
* 获得下周星期日的日期
*/
public String getNextSunday() {
int mondayPlus = this.getMondayPlus();
GregorianCalendar currentDate = new GregorianCalendar();
currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 + 6);
Date monday = currentDate.getTime();
DateFormat df = DateFormat.getDateInstance();
String preMonday = df.format(monday);
return preMonday;
}

private int getMonthPlus() {
Calendar cd = Calendar.getInstance();
int monthOfNumber = cd.get(Calendar.DAY_OF_MONTH);
cd.set(Calendar.DATE, 1);// 把日期设置为当月第一天
cd.roll(Calendar.DATE, -1);// 日期回滚一天，也就是最后一天
MaxDate = cd.get(Calendar.DATE);
if (monthOfNumber == 1) {
return -MaxDate;
} else {
return 1 - monthOfNumber;
}
}

/**
* 获得上月最后一天的日期
*/
public String getPreviousMonthEnd() {
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar lastDate = Calendar.getInstance();
lastDate.add(Calendar.MONTH, -1);// 减一个月
lastDate.set(Calendar.DATE, 1);// 把日期设置为当月第一天
lastDate.roll(Calendar.DATE, -1);// 日期回滚一天，也就是本月最后一天
str = sdf.format(lastDate.getTime());
return str;
}

/**
* 获得下个月第一天的日期
*/
public String getNextMonthFirst() {
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar lastDate = Calendar.getInstance();
lastDate.add(Calendar.MONTH, 1);// 减一个月
lastDate.set(Calendar.DATE, 1);// 把日期设置为当月第一天
str = sdf.format(lastDate.getTime());
return str;
}

/**
* 获得下个月最后一天的日期
*/
public String getNextMonthEnd() {
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar lastDate = Calendar.getInstance();
lastDate.add(Calendar.MONTH, 1);// 加一个月
lastDate.set(Calendar.DATE, 1);// 把日期设置为当月第一天
lastDate.roll(Calendar.DATE, -1);// 日期回滚一天，也就是本月最后一天
str = sdf.format(lastDate.getTime());
return str;
}

/**
* 获得明年最后一天的日期
*/
public String getNextYearEnd() {
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar lastDate = Calendar.getInstance();
lastDate.add(Calendar.YEAR, 1);// 加一个年
lastDate.set(Calendar.DAY_OF_YEAR, 1);
lastDate.roll(Calendar.DAY_OF_YEAR, -1);
str = sdf.format(lastDate.getTime());
return str;
}

/**
* 获得明年第一天的日期
*/
public String getNextYearFirst() {
String str = "";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
Calendar lastDate = Calendar.getInstance();
lastDate.add(Calendar.YEAR, 1);// 加一个年
lastDate.set(Calendar.DAY_OF_YEAR, 1);
str = sdf.format(lastDate.getTime());
return str;
}

/**
* 获得本年有多少天
*
* @return
*/
private int getMaxYear() {
Calendar cd = Calendar.getInstance();
cd.set(Calendar.DAY_OF_YEAR, 1);// 把日期设为当年第一天
cd.roll(Calendar.DAY_OF_YEAR, -1);// 把日期回滚一天。
int MaxYear = cd.get(Calendar.DAY_OF_YEAR);
return MaxYear;
}

private int getYearPlus() {
Calendar cd = Calendar.getInstance();
int yearOfNumber = cd.get(Calendar.DAY_OF_YEAR);// 获得当天是一年中的第几天
cd.set(Calendar.DAY_OF_YEAR, 1);// 把日期设为当年第一天
cd.roll(Calendar.DAY_OF_YEAR, -1);// 把日期回滚一天。
int MaxYear = cd.get(Calendar.DAY_OF_YEAR);
if (yearOfNumber == 1) {
return -MaxYear;
} else {
return 1 - yearOfNumber;
}
}

/**
* 获得本年第一天的日期
*
* @return
*/
public String getCurrentYearFirst() {
int yearPlus = this.getYearPlus();
GregorianCalendar currentDate = new GregorianCalendar();
currentDate.add(GregorianCalendar.DATE, yearPlus);
Date yearDay = currentDate.getTime();
DateFormat df = DateFormat.getDateInstance();
String preYearDay = df.format(yearDay);
return preYearDay;
}

/**
* 获得本年最后一天的日期
*
* @return
*/
public String getCurrentYearEnd() {
Date date = new Date();
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");// 可以方便地修改日期格式
String years = dateFormat.format(date);
return years + "-12-31";
}

/**
* 获得上年第一天的日期
*
* @return
*/
public String getPreviousYearFirst() {
Date date = new Date();
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");// 可以方便地修改日期格式
String years = dateFormat.format(date);
int years_value = Integer.parseInt(years);
years_value--;
return years_value + "-1-1";
}

/**
* 获得上年最后一天的日期
*
* @return
*/
public String getPreviousYearEnd() {
weeks--;
int yearPlus = this.getYearPlus();
GregorianCalendar currentDate = new GregorianCalendar();
currentDate.add(GregorianCalendar.DATE, yearPlus + MaxYear * weeks + (MaxYear - 1));
Date yearDay = currentDate.getTime();
DateFormat df = DateFormat.getDateInstance();
String preYearDay = df.format(yearDay);
getThisSeasonTime(11);
return preYearDay;
}

/**
* 获得本季度
*
* @param month
* @return
*/
public String getThisSeasonTime(int month) {
int array[][] = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 }, { 10, 11, 12 } };
int season = 1;
if (month >= 1 && month <= 3) {
season = 1;
}
if (month >= 4 && month <= 6) {
season = 2;
}
if (month >= 7 && month <= 9) {
season = 3;
}
if (month >= 10 && month <= 12) {
season = 4;
}
int start_month = array[season - 1][0];
int end_month = array[season - 1][2];
Date date = new Date();
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");// 可以方便地修改日期格式
String years = dateFormat.format(date);
int years_value = Integer.parseInt(years);
int start_days = 1;// years+"-"+String.valueOf(start_month)+"-1";//getLastDayOfMonth(years_value,start_month);
int end_days = getLastDayOfMonth(years_value, end_month);
String seasonDate = years_value + "-" + start_month + "-" + start_days + ";" + years_value + "-" + end_month + "-" + end_days;
return seasonDate;
}

/**
* 获取某年某月的最后一天
*
* @param year
*            年
* @param month
*            月
* @return 最后一天
*/
private int getLastDayOfMonth(int year, int month) {
if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) {
return 31;
}
if (month == 4 || month == 6 || month == 9 || month == 11) {
return 30;
}
if (month == 2) {
if (isLeapYear(year)) {
return 29;
} else {
return 28;
}
}
return 0;
}

/**
* 是否闰年
*
* @param year
*            年
* @return
*/
public boolean isLeapYear(int year) {
return (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
}
}