datec.java

很不错的结合DateTime的综合例子

/**
 * 日期转换
 * */

package com.lianjiping.demoa;

import java.sql.Date;
import java.util.Calendar;

public class DateC {
    public static Date getSqlDate(java.util.Date date) {
        return new Date(date.getTime());
    }

    public static Date nowDate() {
        Calendar calendar = Calendar.getInstance();
        return getSqlDate(calendar.getTime());
    }

    //获得某一日期的后一天
    public static Date getNextDate(Date date) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        int day = calendar.get(Calendar.DATE);
        calendar.set(Calendar.DATE, day + 1);
        return getSqlDate(calendar.getTime());
    }

    //获得某一日期的前一天
    public static Date getPreviousDate(Date date) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        int day = calendar.get(Calendar.DATE);
        calendar.set(Calendar.DATE, day - 1);
        return getSqlDate(calendar.getTime());
    }

    //获得某年某月第一天的日期
    public static Date getFirstDayOfMonth(int year, int month) {
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.YEAR, year);
        calendar.set(Calendar.MONTH, month - 1);
        calendar.set(Calendar.DATE, 1);
        return getSqlDate(calendar.getTime());
    }

    //获得某年某月最后一天的日期
    public static Date getLastDayOfMonth(int year, int month) {
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.YEAR, year);
        calendar.set(Calendar.MONTH, month);
        calendar.set(Calendar.DATE, 1);
        return getPreviousDate(getSqlDate(calendar.getTime()));
    }

    //由年月日构建java.sql.Date类型
    public static Date buildDate(int year, int month, int date) {
        Calendar calendar = Calendar.getInstance();
        calendar.set(year, month - 1, date);
        return getSqlDate(calendar.getTime());
    }

    //取得某月的天数
    public static int getDayCountOfMonth(int year, int month) {
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.YEAR, year);
        calendar.set(Calendar.MONTH, month);
        calendar.set(Calendar.DATE, 0);
        return calendar.get(Calendar.DATE);
    }

    //获得某年某季度最后一天的日期
    public static Date getLastDayOfQuarter(int year, int quarter) {
        int month = 0;
        if (quarter > 4) {
            return null;
        } else {
            month = quarter * 3;
        }
        return getLastDayOfMonth(year, month);
    }

    //获得某年某季度的第一天的日期
    public static Date getFirstDayOfQuarter(int year, int quarter) {
        int month = 0;
        if (quarter > 4) {
            return null;
        } else {
            month = (quarter - 1) * 3 + 1;
        }
        return getFirstDayOfMonth(year, month);
    }

    //获得某年的第一天的日期
    public static Date getFirstDayOfYear(int year) {
        return getFirstDayOfMonth(year, 1);
    }

    //获得某年的最后一天的日期
    public static Date getLastDayOfYear(int year) {
        return getLastDayOfMonth(year, 12);
    }
}