前言
在項目中常常會使用到日期處理的方法，花費了一點時間整理下我使用過的方法，整合成工具類，方便之後使用。java
工具類
package cc.vvxtoys.util;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
/**
*
* @author vvxtoys
* @date 2018年1月6日下午9:48:02
*
*/
public class DateUtils {
private static Calendar cal = Calendar.getInstance();
private static String fm = "";//format month
private static String fd = "";//format day
/**
* @description 判斷是否爲閏年
*/
public static boolean isLeapYear(int year){
return (year % 400 == 0) || (year % 4 == 0 && year % 100 != 0);
}
/**
*
* @description 獲取月天數
*/
public static String getMonthDays(int year,int month){
String [] days = {"31", null, "31", "30", "31", "30", "31", "31", "30", "31", "30", "31"};
if(isLeapYear(year)){
days[1]="29";
}else{
days[1]="28";
}
return days[month-1];
}
/**
* @description 獲取時間在當前年爲第幾周
*/
public static int getWeekOfYear(String date) throws ParseException {
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
cal.setFirstDayOfWeek(Calendar.MONDAY);
String firstDay = date.substring(0, 4) + "-01-01";
cal.setTime(sdf.parse(firstDay));
int dayOfWeek = cal.get(Calendar.DAY_OF_WEEK);
if (dayOfWeek == 2) {
cal.setTime(sdf.parse(date));
int num = cal.get(Calendar.WEEK_OF_YEAR);
return num;
} else {
cal.setTime(sdf.parse(date));
int num = cal.get(Calendar.WEEK_OF_YEAR) - 1;
return num;
}
}
/**
*
* @description 天計算
*/
public static String addDays(String date,int num){
try{
cal.setTime(toDate(date));
cal.add(Calendar.DATE, num);
toFormatDate();
}catch(Exception e){
e.printStackTrace();
}
return cal.get(Calendar.YEAR) + "-"+fm+"-"+fd;
}
/**
*
* @description 星期
*/
public static String addWeeks(String date,int num){
try {
cal.setTime(toDate(date));
cal.add(Calendar.WEEK_OF_YEAR, num);
toFormatDate();
} catch (ParseException e) {
e.printStackTrace();
}
return cal.get(Calendar.YEAR) + "-"+fm+"-"+fd;
}
/**
*
* @description 月
*/
public static String addMonths(String date,int num){
try {
cal.setTime(toDate(date));
cal.add(Calendar.MONTH, num);
toFormatDate();
} catch (ParseException e) {
e.printStackTrace();
}
return cal.get(Calendar.YEAR) + "-"+fm+"-"+fd;
}
/**
*
* @description 季度
*/
public static String addQuarters(String date,int num){
try {
cal.setTime(toDate(date));
cal.add(Calendar.MONTH, num*3);
toFormatDate();
} catch (ParseException e) {
e.printStackTrace();
}
return cal.get(Calendar.YEAR) + "-"+fm+"-"+fd;
}
/**
*
* @description 年
*/
public static String addYears(String date,int num){
try {
cal.setTime(toDate(date));
cal.add(Calendar.YEAR, num);
toFormatDate();
} catch (ParseException e) {
e.printStackTrace();
}
return cal.get(Calendar.YEAR) + "-"+fm+"-"+fd;
}
/**
*
* @description 日期轉換
*/
public static Object translateDate(Object time, String pattern) {
Object date = new Object();
if (isEmpty(pattern)) {
pattern = "yyyy-MM-dd";
}
if (isEmpty(time)) {
time = "1970-1-1";
}
SimpleDateFormat sdf = new SimpleDateFormat(pattern);
try {
if (time instanceof String) {
date = sdf.parse((String) time);
} else if (time instanceof Date) {
date = sdf.format(time);
} else {
throw new Exception("轉換失敗");
}
} catch (Exception e) {
e.printStackTrace();
}
return date;
}
/**
*
* @description 當前日期爲本週第幾天
*/
public static int getDayOfWeek(String date){
try{
cal.setTime(toDate(date));
cal.setFirstDayOfWeek(Calendar.MONDAY);
}catch(ParseException e){
e.printStackTrace();
}
return cal.get(Calendar.DAY_OF_WEEK)==1?7:cal.get(Calendar.DAY_OF_WEEK)-1;
}
/**
*
* @description 週一
*/
public static String getStartDayOfThisWeek(String date){
return addDays(date, -(getDayOfWeek(date)-1));
}
/**
*
* @description 週日
*/
public static String getEndDayOfThisWeek(String date){
return addDays(date,(7-getDayOfWeek(date)));
}
//獲取當前時間
public static String getCurrentDate(){
Date date = new Date();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
return sdf.format(date);
}
//當前時間
public static String getCurrentDate(String pattern){
Date date = new Date();
if(isEmpty(pattern)){
pattern = "yyyy-MM-dd";
}
SimpleDateFormat sdf = new SimpleDateFormat(pattern);
return sdf.format(date);
}
/**
*
* @description 時間間隔 月 季度 年 *3 *12
*/
public static int getSubDays(int num){
Date date = new Date();
cal.setTime(date);
cal.add(Calendar.MONTH, num);
long time = cal.getTimeInMillis() - date.getTime();
return (int) (time / (1000 * 60 * 60 * 24));
}
/**
*
* @description 獲取第幾周開始時間
*/
public static String getStartDayOfWeek(int year,int num){
cal.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY);
cal.set(Calendar.YEAR, year);
cal.set(Calendar.WEEK_OF_YEAR, num);
toFormatDate();
return cal.get(Calendar.YEAR) + "-"+fm+"-"+fd;
}
/**
*
* @description 獲取第幾周結束時間
*/
public static String getEndDayOfWeek(int year,int num){
cal.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY);
cal.set(Calendar.YEAR, year);
cal.set(Calendar.WEEK_OF_YEAR, num);
cal.add(Calendar.DAY_OF_WEEK, 6);
toFormatDate();
return cal.get(Calendar.YEAR) + "-"+fm+"-"+fd;
}
/**
*
* @description 獲取第幾月開始時間
*/
public static String getStartDayOfMonth(int year,int num){
String month = num < 10 ? "0" + num : String.valueOf(num);
return year + "-" + month + "-" + "01";
}
/**
*
* @description 獲取第幾月結束時間
*/
public static String getEndDayOfMonth(int year,int num){
cal.set(Calendar.YEAR, year);
cal.set(Calendar.MONTH, num - 1);
cal.set(Calendar.DATE, 1);
cal.add(Calendar.MONTH, 1);
cal.add(Calendar.DAY_OF_YEAR, -1);
toFormatDate();
return cal.get(Calendar.YEAR) + "-"+fm+"-"+fd;
}
//獲取第幾季度開始時間
public static String getStartDayOfQuarter(int year,int num){
num = 3 * num - 2;
String month = num < 10 ? "0" + num : String.valueOf(num);
return year + "-" + month + "-" + "01";
}
//獲取第幾季度結束時間
public static String getEndDayOfQuarter(int year,int num){
cal.set(Calendar.YEAR, year);
cal.set(Calendar.MONTH, 3 * num - 1);
cal.set(Calendar.DATE, 1);
cal.add(Calendar.MONTH, 1);
cal.add(Calendar.DAY_OF_YEAR, -1);
toFormatDate();
return cal.get(Calendar.YEAR) + "-"+fm+"-"+fd;
}
//時間間隔
public static int intervalDay(String d1,String d2){
int num = 0;
try{
long second = toDate(d2).getTime()-toDate(d1).getTime();
num=(int)(Math.abs(second)/(1000 * 60 * 60 * 24));
}catch(ParseException e){
e.printStackTrace();
}
return num;
}
private static void toFormatDate(){
int month = (cal.get(Calendar.MONTH) + 1);
fm = month<10?"0"+month:String.valueOf(month);
int day = cal.get(Calendar.DAY_OF_MONTH);
fd = day<10?"0"+day:String.valueOf(day);
}
private static Date toDate(String date) throws ParseException{
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
return sdf.parse(date);
}
private static boolean isEmpty(Object obj){
return obj==null||obj.toString().trim().equals("");
}
}