日历工具类

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


/**
 * 日期时间相关函数
 * @author jacob
 */
public class CalendarUtil {

/**
* String转为Date
* @param str
* @return
*/
public static Date stringToDate(String str) { 
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = sdf.parse(str);
} catch (ParseException e) {
e.printStackTrace();
}
return date;
    } 
/**
* date转为String
* @param date
* @return
*/
public static String dateToString(Date date){
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
String dateStr=sdf.format(date);
return dateStr;
}
/**
* 比较两个时间大小
* @param date1
* @param date2
* @return
*/
public static int compare_date(String date1, String date2) {
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
        try {
            Date dt1 = df.parse(date1);
            Date dt2 = df.parse(date2);
            if (dt1.getTime() > dt2.getTime()) {
                System.out.println("dt1>dt2");
                return 1;
            } else if (dt1.getTime() < dt2.getTime()) {
                System.out.println("dt1<dt2");
                return -1;
            } else {
                return 0;
            }
        } catch (ParseException e) {
            e.printStackTrace();
        }
        return 0;
    }
/**
* 日期加一天
* @param date
* @return
*/
public static Date addDateOneDay(Date date){   
        Calendar c = Calendar.getInstance();   
        c.setTime(date);   //设置当前日期   
        c.add(Calendar.DATE, 1); //日期加1天   
        date = c.getTime();   
        return date;   
}  
/**
* 日期加一天
* @param dateStr
* @return
*/
public static String addDateOneDay(String dateStr){
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = sdf.parse(dateStr);
} catch (ParseException e) {
e.printStackTrace();
}

Calendar c = Calendar.getInstance();   
        c.setTime(date);   //设置当前日期   
        c.add(Calendar.DATE, 1); //日期加1天   
        date = c.getTime();   
         
        SimpleDateFormat sdf2= new SimpleDateFormat("yyyy-MM-dd");
String dateStr2=sdf2.format(date);
return dateStr2;
}
/**
* 日期减一天
* @param date
* @return
*/
public static Date minusDateOneDay(Date date){   
        Calendar c = Calendar.getInstance();   
        c.setTime(date);   //设置当前日期   
        c.add(Calendar.DATE, -1); //日期减1天   
        date = c.getTime();   
        return date;   
}  
/**
* 日期减一天
* @param dateStr
* @return
*/
public static String minusDateOneDay(String dateStr){
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = sdf.parse(dateStr);
} catch (ParseException e) {
e.printStackTrace();
}

Calendar c = Calendar.getInstance();   
c.setTime(date);   //设置当前日期   
c.add(Calendar.DATE, -1); //日期减1天   
date = c.getTime();   
  
SimpleDateFormat sdf2= new SimpleDateFormat("yyyy-MM-dd");
String dateStr2=sdf2.format(date);
return dateStr2;
}
/**
* 得到指定日期的第一天（周一）
* @param date
* @return
*/
public static Date getMonday(Date date){  
        Calendar cDay = Calendar.getInstance();     
//        cDay.setTime(date);     
//        cDay.set(Calendar.DAY_OF_WEEK, 2);//老外将周日定位第一天，周一取第二天  
        cDay.setFirstDayOfWeek(Calendar.MONDAY);  
        cDay.setTime(date);  
        cDay.set(Calendar.DAY_OF_WEEK, cDay.getFirstDayOfWeek());
        return cDay.getTime();     
    } 
/**
* 得到指定日期的第一天（周一）
* @param dateStr
* @return
*/
public static String getMonday(String dateStr){  
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = sdf.parse(dateStr);
} catch (ParseException e) {
e.printStackTrace();
}

        Calendar cDay = Calendar.getInstance();     
        cDay.setFirstDayOfWeek(Calendar.MONDAY);  
        cDay.setTime(date);  
        cDay.set(Calendar.DAY_OF_WEEK, cDay.getFirstDayOfWeek());   
        Date date2 = cDay.getTime();
        
        SimpleDateFormat sdf2= new SimpleDateFormat("yyyy-MM-dd");
String dateStr2=sdf2.format(date2);
return dateStr2;
    }  
/**
* 获得指定日期所在周日
* @param date
* @return
*/
public static Date getSunday(Date date){  
        Calendar cDay = Calendar.getInstance();   
        cDay.setTime(date);  
        if(cDay.get(Calendar.DAY_OF_WEEK)==cDay.getFirstDayOfWeek()){ //如果刚好是周日，直接返回  
            return date;  
        }else{//如果不是周日，加一周计算  
            cDay.add(Calendar.DAY_OF_YEAR, 7);  
            cDay.set(Calendar.DAY_OF_WEEK, 1);  
            return cDay.getTime();  
        }    
    
  
    }
/**
* 获得指定日期所在周日
* @param dateStr
* @return
*/
public static String getSunday(String dateStr){
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = sdf.parse(dateStr);
} catch (ParseException e) {
e.printStackTrace();
}

Calendar cDay = Calendar.getInstance();     
        cDay.setTime(date);  
        if(cDay.get(Calendar.DAY_OF_WEEK)==cDay.getFirstDayOfWeek()){ //如果刚好是周日，直接返回  
            return dateStr;  
        }else{//如果不是周日，加一周计算  
            cDay.add(Calendar.DAY_OF_YEAR, 7);  
            cDay.set(Calendar.DAY_OF_WEEK, 1);  
            Date date2 = cDay.getTime();  
            SimpleDateFormat sdf2= new SimpleDateFormat("yyyy-MM-dd");
    String dateStr2=sdf2.format(date2);
    return dateStr2;
        }   
        
}
/**
* 获得本月第一天
* @param date
* @return
*/
public static Date getFirstDayOfMonth(Date date){     
        Calendar cDay = Calendar.getInstance();     
        cDay.setTime(date);  
        cDay.set(Calendar.DAY_OF_MONTH, 1);  
        return cDay.getTime();     
    }  
/**
* 获得本月第一天
* @param dateStr
* @return
*/
public static String getFirstDayOfMonth(String dateStr){
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = sdf.parse(dateStr);
} catch (ParseException e) {
e.printStackTrace();
}

Calendar cDay = Calendar.getInstance();     
        cDay.setTime(date);  
        cDay.set(Calendar.DAY_OF_MONTH, 1);  
        Date date2 = cDay.getTime();        


        SimpleDateFormat sdf2= new SimpleDateFormat("yyyy-MM-dd");
String dateStr2=sdf2.format(date2);
return dateStr2;
}
/**
* 获得本月最后一天
* @param date
* @return
*/
public static Date getLastDayOfMonth(Date date)   {     
        Calendar cDay = Calendar.getInstance();     
        cDay.setTime(date);  
        cDay.set(Calendar.DAY_OF_MONTH, cDay.getActualMaximum(Calendar.DAY_OF_MONTH));  
        return cDay.getTime();     
    } 
/**
* 获得本月最后一天
* @param dateStr
* @return
*/
public static String getLastDayOfMonth(String dateStr){
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = sdf.parse(dateStr);
} catch (ParseException e) {
e.printStackTrace();
}

Calendar cDay = Calendar.getInstance();     
        cDay.setTime(date);  
        cDay.set(Calendar.DAY_OF_MONTH, cDay.getActualMaximum(Calendar.DAY_OF_MONTH));  
        Date date2 = cDay.getTime();        
       
        SimpleDateFormat sdf2= new SimpleDateFormat("yyyy-MM-dd");
String dateStr2=sdf2.format(date2);
return dateStr2;
}
/**
* 获得本季度第一天日期
* @param date
* @return
*/
public static Date getFirstDayOfQuarter(Date date){     
        Calendar cDay = Calendar.getInstance();     
        cDay.setTime(date);  
        int curMonth = cDay.get(Calendar.MONTH);  
        if (curMonth >= Calendar.JANUARY && curMonth <= Calendar.MARCH){    
            cDay.set(Calendar.MONTH, Calendar.JANUARY);  
        }  
        if (curMonth >= Calendar.APRIL && curMonth <= Calendar.JUNE){    
            cDay.set(Calendar.MONTH, Calendar.APRIL);  
        }  
        if (curMonth >= Calendar.JULY && curMonth <= Calendar.SEPTEMBER) {    
            cDay.set(Calendar.MONTH, Calendar.JULY);  
        }  
        if (curMonth >= Calendar.OCTOBER && curMonth <= Calendar.DECEMBER) {    
            cDay.set(Calendar.MONTH, Calendar.OCTOBER);  
        }  
        cDay.set(Calendar.DAY_OF_MONTH, cDay.getActualMinimum(Calendar.DAY_OF_MONTH));  
        return cDay.getTime();     
    } 
/**
* 获得本季度第一天日期
* @param dateStr
* @return
*/
public static String getFirstDayOfQuarter(String dateStr){
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = sdf.parse(dateStr);
} catch (ParseException e) {
e.printStackTrace();
}

Calendar cDay = Calendar.getInstance();     
cDay.setTime(date);  
int curMonth = cDay.get(Calendar.MONTH);  
if (curMonth >= Calendar.JANUARY && curMonth <= Calendar.MARCH){    
cDay.set(Calendar.MONTH, Calendar.JANUARY);  
}  
if (curMonth >= Calendar.APRIL && curMonth <= Calendar.JUNE){    
cDay.set(Calendar.MONTH, Calendar.APRIL);  
}  
if (curMonth >= Calendar.JULY && curMonth <= Calendar.SEPTEMBER) {    
cDay.set(Calendar.MONTH, Calendar.JULY);  
}  
if (curMonth >= Calendar.OCTOBER && curMonth <= Calendar.DECEMBER) {    
cDay.set(Calendar.MONTH, Calendar.OCTOBER);  
}  
cDay.set(Calendar.DAY_OF_MONTH, cDay.getActualMinimum(Calendar.DAY_OF_MONTH));  
Date date2 = cDay.getTime();  
 
SimpleDateFormat sdf2= new SimpleDateFormat("yyyy-MM-dd");
String dateStr2=sdf2.format(date2);
return dateStr2;

}
/**
* 获得本季度最后一天日期
* @param date
* @return
*/
public static Date getLastDayOfQuarter(Date date){ 
        Calendar cDay = Calendar.getInstance();     
        cDay.setTime(date);  
        int curMonth = cDay.get(Calendar.MONTH);  
        if (curMonth >= Calendar.JANUARY && curMonth <= Calendar.MARCH){    
            cDay.set(Calendar.MONTH, Calendar.MARCH);  
        }  
        if (curMonth >= Calendar.APRIL && curMonth <= Calendar.JUNE){    
            cDay.set(Calendar.MONTH, Calendar.JUNE);  
        }  
        if (curMonth >= Calendar.JULY && curMonth <= Calendar.SEPTEMBER) {    
            cDay.set(Calendar.MONTH, Calendar.SEPTEMBER);  
        }  
        if (curMonth >= Calendar.OCTOBER && curMonth <= Calendar.DECEMBER) {    
            cDay.set(Calendar.MONTH, Calendar.DECEMBER);  
        }  
        cDay.set(Calendar.DAY_OF_MONTH, cDay.getActualMaximum(Calendar.DAY_OF_MONTH));  
        return cDay.getTime();     
    }  
/**
* 获得本季度最后一天日期
* @param dateStr
* @return
*/
public static String getLastDayOfQuarter(String dateStr){
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = sdf.parse(dateStr);
} catch (ParseException e) {
e.printStackTrace();
}

Calendar cDay = Calendar.getInstance();     
        cDay.setTime(date);  
        int curMonth = cDay.get(Calendar.MONTH);  
        if (curMonth >= Calendar.JANUARY && curMonth <= Calendar.MARCH){    
            cDay.set(Calendar.MONTH, Calendar.MARCH);  
        }  
        if (curMonth >= Calendar.APRIL && curMonth <= Calendar.JUNE){    
            cDay.set(Calendar.MONTH, Calendar.JUNE);  
        }  
        if (curMonth >= Calendar.JULY && curMonth <= Calendar.SEPTEMBER) {    
            cDay.set(Calendar.MONTH, Calendar.SEPTEMBER);  
        }  
        if (curMonth >= Calendar.OCTOBER && curMonth <= Calendar.DECEMBER) {    
            cDay.set(Calendar.MONTH, Calendar.DECEMBER);  
        }  
        cDay.set(Calendar.DAY_OF_MONTH, cDay.getActualMaximum(Calendar.DAY_OF_MONTH)); 
        Date date2 = cDay.getTime();        
      
SimpleDateFormat sdf2= new SimpleDateFormat("yyyy-MM-dd");
String dateStr2=sdf2.format(date2);
return dateStr2;
}
/**
* 计算两个日期相差多少天
* @param str1
* @param str2
* @return
*/
public static long getDistanceDays(String str1, String str2) { 
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd"); 
        Date one; 
        Date two; 
        long days=0; 
        try { 
            one = df.parse(str1); 
            two = df.parse(str2); 
            long time1 = one.getTime(); 
            long time2 = two.getTime(); 
            long diff ; 
            if(time1<time2) { 
                diff = time2 - time1; 
            } else { 
                diff = time1 - time2; 
            } 
            days = diff / (1000 * 60 * 60 * 24); 
        } catch (ParseException e) { 
            e.printStackTrace(); 
        } 
        return days; 
    } 
/**
 * 计算两个日期相差多少月
 * @param str1
 * @param str2
 * @return
 */
public static int getDistanceMonths(String str1, String str2){
SimpleDateFormat df  = new SimpleDateFormat("yyyy-MM-dd");
int result=0;
    int months = 0;
    Calendar c = Calendar.getInstance();
    Calendar c2 = Calendar.getInstance();


       try {
c.setTime(df.parse(str1));
c2.setTime(df.parse(str2));
} catch (ParseException e) {
e.printStackTrace();
}
      
       int year1 = c.get(Calendar.YEAR);
       int month1 = c.get(Calendar.MONTH);
       int year2 = c2.get(Calendar.YEAR);
       int month2 = c2.get(Calendar.MONTH);
        
       if(year1 == year2) {
           result = month1 - month2;
       } else {
           result = 12*(year1 - year2) + month1 - month2;
       }
       months = Math.abs(result);
       return months;
}


}