关于时间的一些写法(JAVA)

import java.util.Date;
import java.text.SimpleDateFormat;

public class Test {
public static void main(String[] args) {

Date date = new Date();
String strDate = "";

SimpleDateFormat format = new SimpleDateFormat();
format.applyPattern("yyyy-MM-dd HH:mm:ss");
strDate = format.format(date);
System.out.println(strDate);

format.applyPattern("yyyy-MM-dd");
strDate = format.format(date);
System.out.println(strDate);

format.applyPattern("yyyyMMddHHmmss");
strDate = format.format(date);
System.out.println(strDate);

format.applyPattern("yyyy'年'MM'月'dd'日'");
strDate = format.format(date);
System.out.println(strDate);
}

}

public class bb {
public static void main(String[] args) {
// TODO Auto-generated method stub
SimpleDateFormat df = new SimpleDateFormat("yyyyMMddhhmmss");
String dateString = "20071128175545";
try {
Date date = df.parse(dateString);
System.out.println(date.toLocaleString());
}
catch (Exception ex)
{ System.out.println(ex.getMessage());}
}

}












/**
日期类
* @date 2003-12-04
* @version 1.0
*/

import java.util.*;
import java.text.*;
import java.util.Calendar;

public class VeDate {
/**
* 获取现在时间
*
* @return 返回时间类型 yyyy-MM-dd HH:mm:ss
*/
public static Date getNowDate() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = formatter.format(currentTime);
ParsePosition pos = new ParsePosition(8);
Date currentTime_2 = formatter.parse(dateString, pos);
return currentTime_2;
}

/**
* 获取现在时间
*
* @return返回短时间格式 yyyy-MM-dd
*/
public static Date getNowDateShort() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
String dateString = formatter.format(currentTime);
ParsePosition pos = new ParsePosition(8);
Date currentTime_2 = formatter.parse(dateString, pos);
return currentTime_2;
}

/**
* 获取现在时间
*
* @return返回字符串格式 yyyy-MM-dd HH:mm:ss
*/
public static String getStringDate() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = formatter.format(currentTime);
return dateString;
}

/**
* 获取现在时间
*
* @return 返回短时间字符串格式yyyy-MM-dd
*/
public static String getStringDateShort() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
String dateString = formatter.fo

rmat(currentTime);
return dateString;
}

/**
* 获取时间 小时:分;秒 HH:mm:ss
*
* @return
*/
public static String getTimeShort() {
SimpleDateFormat formatter = new SimpleDateFormat("HH:mm:ss");
Date currentTime = new Date();
String dateString = formatter.format(currentTime);
return dateString;
}

/**
* 将长时间格式字符串转换为时间 yyyy-MM-dd HH:mm:ss
*
* @param strDate
* @return
*/
public static Date strToDateLong(String strDate) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
ParsePosition pos = new ParsePosition(0);
Date strtodate = formatter.parse(strDate, pos);
return strtodate;
}

/**
* 将长时间格式时间转换为字符串 yyyy-MM-dd HH:mm:ss
*
* @param dateDate
* @return
*/
public static String dateToStrLong(java.util.Date dateDate) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = formatter.format(dateDate);
return dateString;
}

/**
* 将短时间格式时间转换为字符串 yyyy-MM-dd
*
* @param dateDate
* @param k
* @return
*/
public static String dateToStr(java.util.Date dateDate) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
String dateString = formatter.format(dateDate);
return dateString;
}

/**
* 将短时间格式字符串转换为时间 yyyy-MM-dd
*
* @param strDate
* @return
*/
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;
}

/**
* 得到现在时间
*
* @return
*/
public static Date getNow() {
Date currentTime = new Date();
return currentTime;
}

/**
* 提取一个月中的最后一天
*
* @param day
* @return
*/
public static Date getLastDate(long day) {
Date date = new Date();
long date_3_hm = date.getTime() - 3600000 * 34 * day;
Date date_3_hm_date = new Date(date_3_hm);
return date_3_hm_date;
}

/**
* 得到现在时间
*
* @return 字符串 yyyyMMdd HHmmss
*/
public static String getStringToday() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyyMMdd HHmmss");
String dateString = formatter.format(currentTime);
return dateString;
}

/**
* 得到现在小时
*/
public static String getHour() {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = formatter.format(currentTime);
String hour;
hour = dateString.substring(11, 13);
return hour;
}

/**
* 得到现在分钟
*
* @return
*/
public static String getTime() {
Date currentTime = new Date();

SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String dateString = formatter.format(currentTime);
String min;
min = dateString.substring(14, 16);
return min;
}

/**
* 根据用户传入的时间表示格式，返回当前时间的格式 如果是yyyyMMdd，注意字母y不能大写。
*
* @param sformat
* yyyyMMddhhmmss
* @return
*/
public static String getUserDate(String sformat) {
Date currentTime = new Date();
SimpleDateFormat formatter = new SimpleDateFormat(sformat);
String dateString = formatter.format(currentTime);
return dateString;
}



续：自己参考一下
/**
* 二个小时时间间的差值,必须保证二个时间都是"HH:MM"的格式，返回字符型的分钟
*/
public static String getTwoHour(String st1, String st2) {
String[] kk = null;
String[] jj = null;
kk = st1.split(":");
jj = st2.split(":");
if (Integer.parseInt(kk[0]) < Integer.parseInt(jj[0]))
return "0";
else {
double y = Double.parseDouble(kk[0]) + Double.parseDouble(kk[1]) / 60;
double u = Double.parseDouble(jj[0]) + Double.parseDouble(jj[1]) / 60;
if ((y - u) > 0)
return y - u + "";
else
return "0";
}
}

/**
* 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 + "";
}

/**
* 时间前推或后推分钟,其中JJ表示分钟.
*/
public static String getPreTime(String sj1, String jj) {
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String mydate1 = "";
try {
Date date1 = format.parse(sj1);
long Time = (date1.getTime() / 1000) + Integer.parseInt(jj) * 60;
date1.setTime(Time * 1000);
mydate1 = format.format(date1);
} catch (Exception e) {
}
return mydate1;
}

/**
* 得到一个时间延后或前移几天的时间,nowdate为时间,delay为前移或后延的天数
*/
public static String getNextDay(String nowdate, String delay) {
try{
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
String mdate = "";
Date d = strToDate(nowdate);
long myTime = (d.getTime() / 1000) + Integer.parseInt(delay) * 24 * 60 * 60;
d.setTime(myTime * 1000);
mdate = format.format(d);
return mdate;
}catch(Exception e){
return "";
}
}

/**
* 判断是否润年
*
* @param ddate
* @return
*/
public static boolean isLeapYear(String ddate) {

/**
* 详细设计： 1.被400整除是闰年，否则： 2.不能被4整除则不是闰年 3.能被4整除同

时不能被100整除则是闰年
* 3.能被4整除同时能被100整除则不是闰年
*/
Date d = strToDate(ddate);
GregorianCalendar gc = (GregorianCalendar) Calendar.getInstance();
gc.setTime(d);
int year = gc.get(Calendar.YEAR);
if ((year % 400) == 0)
return true;
else if ((year % 4) == 0) {
if ((year % 100) == 0)
return false;
else
return true;
} else
return false;
}

/**
* 返回美国时间格式 26 Apr 2006
*
* @param str
* @return
*/
public static String getEDate(String str) {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
ParsePosition pos = new ParsePosition(0);
Date strtodate = formatter.parse(str, pos);
String j = strtodate.toString();
String[] k = j.split(" ");
return k[2] + k[1].toUpperCase() + k[5].substring(2, 4);
}

/**
* 获取一个月的最后一天
*
* @param dat
* @return
*/
public static String getEndDateOfMonth(String dat) {// yyyy-MM-dd
String str = dat.substring(0, 8);
String month = dat.substring(5, 7);
int mon = Integer.parseInt(month);
if (mon == 1 || mon == 3 || mon == 5 || mon == 7 || mon == 8 || mon == 10 || mon == 12) {
str += "31";
} else if (mon == 4 || mon == 6 || mon == 9 || mon == 11) {
str += "30";
} else {
if (isLeapYear(dat)) {
str += "29";
} else {
str += "28";
}
}
return str;
}

/**
* 判断二个时间是否在同一个周
*
* @param date1
* @param date2
* @return
*/
public static boolean isSameWeekDates(Date date1, Date date2) {
Calendar cal1 = Calendar.getInstance();
Calendar cal2 = Calendar.getInstance();
cal1.setTime(date1);
cal2.setTime(date2);
int subYear = cal1.get(Calendar.YEAR) - cal2.get(Calendar.YEAR);
if (0 == subYear) {
if (cal1.get(Calendar.WEEK_OF_YEAR) == cal2.get(Calendar.WEEK_OF_YEAR))
return true;
} else if (1 == subYear && 11 == cal2.get(Calendar.MONTH)) {
// 如果12月的最后一周横跨来年第一周的话则最后一周即算做来年的第一周
if (cal1.get(Calendar.WEEK_OF_YEAR) == cal2.get(Calendar.WEEK_OF_YEAR))
return true;
} else if (-1 == subYear && 11 == cal1.get(Calendar.MONTH)) {
if (cal1.get(Calendar.WEEK_OF_YEAR) == cal2.get(Calendar.WEEK_OF_YEAR))
return true;
}
return false;
}


}




数据库中的Date一般对应java.sql.Date或java.sql.Timestamp

java.util.Date d = ...;
java.sql.Date sd = new java.sql.Date(d.getTime());