Java中怎么对日期类进行处理

今天就跟大家聊聊有关Java中怎么对日期类进行处理，可能很多人都不太了解，为了让大家更加了解，小编给大家总结了以下内容，希望大家根据这篇文章可以有所收获。

具体如下：

import java.text.ParseException;import java.text.SimpleDateFORMat;import java.util.Calendar;import java.util.Date;public class FormatTime {  private final static SimpleDateFormat sdf=new SimpleDateFormat("yyyyMMdd");  private final static SimpleDateFormat sdfymdhm = new SimpleDateFormat("yyyyMMddHHmmss");  private final static SimpleDateFormat sdfymdhms =  new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");    public static String getCurrentDay(){    return sdf.format(new Date());  }    public static String fTime(String time,int dayAGo){    Date date = null;    try {      date = sdf.parse(time);    } catch (ParseException e) {        throw new RuntimeException(e);    }    Calendar calendar = Calendar.getInstance();    calendar.setTime(date);    if(dayAgo>0){      calendar.add(Calendar.DAY_OF_MONTH, -dayAgo);//前15天数据      date = calendar.getTime();      calendar.setTime(date);    }    int year=calendar.get(Calendar.YEAR);    int month=calendar.get(Calendar.MONTH) + 1;    int day = calendar.get(Calendar.DAY_OF_MONTH);    String mon="";    String d="";    if(month<10){      mon="0"+month;    }else{      mon=month+"";    }    if(day<10){      d="0"+day;    }else{      d=""+day;    }    String ret=year+""+mon+""+d;    return ret;  }    public static String fTime2(String time,int dayAfter){    Date date = null;    try {      date = sdf.parse(time);    } catch (ParseException e) {        throw new RuntimeException(e);    }    Calendar calendar = Calendar.getInstance();    calendar.setTime(date);    if(dayAfter>0){      calendar.add(Calendar.DAY_OF_MONTH, +dayAfter);//后15天数据      date = calendar.getTime();      calendar.setTime(date);    }    int year=calendar.get(Calendar.YEAR);    int month=calendar.get(Calendar.MONTH) + 1;    int day = calendar.get(Calendar.DAY_OF_MONTH);    String mon="";    String d="";    if(month<10){      mon="0"+month;    }else{      mon=month+"";    }    if(day<10){      d="0"+day;    }else{      d=""+day;    }    String ret=year+""+mon+""+d;    return ret;  }    public static String getDefaultTime(){    Calendar calendar = Calendar.getInstance();    calendar.add(Calendar.DAY_OF_MONTH, -1);//前1天    Date date = calendar.getTime();    String time=sdf.format(date);    return time;  }    public static String getSunday(){    SimpleDateFormat f = new SimpleDateFormat("yyyyMMdd");    Calendar c = Calendar.getInstance();    c.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);    return f.format(c.getTime());  }    public static String getCurrentMonthFirstDay(){    Calendar  cal_1=Calendar.getInstance();//获取当前日期    cal_1.add(Calendar.MONTH, 0);    cal_1.set(Calendar.DAY_OF_MONTH,1);//设置为1号,当前日期既为本月第一天    String firstDay = sdf.format(cal_1.getTime());    return firstDay;  }    public static String getPreviousMonthFirstDay(){   //获取当前月第一天：  Calendar c = Calendar.getInstance();  c.add(Calendar.MONTH, -1);  c.set(Calendar.DAY_OF_MONTH,1);//设置为1号,当前日期既为本月第一天  String first = sdf.format(c.getTime());  return first;  }    public static String getPreviousMonthLastDay(){  //获取当前月最后一天  Calendar ca = Calendar.getInstance();  ca.set(Calendar.DAY_OF_MONTH,0);//  String lastDay = sdf.format(ca.getTime());  return lastDay;  }    public static String getCurrentMonthLastDay(String time){    Date date =null;   try {    date= sdf.parse(time);  } catch (ParseException e) {    // TODO Auto-generated catch block    e.printStackTrace();  }  //获取当前月最后一天  Calendar ca = Calendar.getInstance();  ca.setTime(date);  ca.set(Calendar.DAY_OF_MONTH,      ca.getActualMaximum(Calendar.DAY_OF_MONTH)); //  String lastDay = sdf.format(ca.getTime());  return lastDay;  }    public static String getCurrentMonday(){     Calendar cal = Calendar.getInstance();     cal.setFirstDayOfWeek(Calendar.MONDAY);//将每周第一天设为星期一，默认是星期天     cal.add(Calendar.DATE, 0);     cal.set(Calendar.DAY_OF_WEEK,Calendar.MONDAY);     String monday = sdf.format(cal.getTime());     return monday;  }    public static String getPreviousSunday(){     Calendar cal = Calendar.getInstance();     cal.setFirstDayOfWeek(Calendar.MONDAY);//将每周第一天设为星期一，默认是星期天     cal.add(Calendar.DATE, -1*7);     cal.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);     String sunday =sdf.format(cal.getTime());     return sunday;  }    public static String getMiniSencond(String str){    long millionSeconds=0;    try {      millionSeconds = sdfymdhm.parse(str).getTime();//毫秒    } catch (ParseException e) {      // TODO Auto-generated catch block      e.printStackTrace();    }    return millionSeconds+"";  }     public static long getDateSencond(String str){    long millionSeconds=0;    try {      millionSeconds = sdfymdhms.parse(str).getTime();//毫秒    } catch (ParseException e) {      // TODO Auto-generated catch block      e.printStackTrace();    }    return millionSeconds;  }    public static int getDistanceOfTwoDate(String str1,String str2){    int result=0;    try{      Date date1 = sdf.parse(str1);      Date date2 =sdf.parse(str2);      Calendar aCalendar = Calendar.getInstance();        aCalendar.setTime(date1);        int day1 = aCalendar.get(Calendar.DAY_OF_YEAR);        aCalendar.setTime(date2);        int day2 = aCalendar.get(Calendar.DAY_OF_YEAR);        result = day1-day2;    }catch(Exception e){      e.printStackTrace();    }    return result;  }    public static String longToDate(Long msecond){    Date date = new Date(msecond);    return sdfymdhms.format(date);  }}