backend_code/wanzai/src/main/java/com/template/common/utils/DateUtils.java

package com.template.common.utils;

import org.springframework.stereotype.Component;

import java.sql.Timestamp;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

/**
 * <p>Title: DateUtils</p>
 * <p>Description:日期工具类 </p>
 *
 * @author fengyong
 * @date 2018年9月7日
 */
@Component // 加此注解是把此类实例化spring容器中
public class DateUtils {

	/**
	 * 默认日期格式
	 */
	public static final String DEFAULT_FORMAT = "yyyy-MM-dd HH:mm:ss";

	/**
	 * 如2018 0901 232211(年月日时分秒)
	 *
	 * @return
	 */
	public String yyyyMMddHHmmss() {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
		return sdf.format(Calendar.getInstance().getTime());
	}

	/**
	 * 如20180901
	 *
	 * @return
	 */
	public static String getYYYYMMdd() {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
		return sdf.format(Calendar.getInstance().getTime());
	}

	/**
	 * 如180901
	 * @return
	 */
	public String getYYMMdd() {
		SimpleDateFormat sdf = new SimpleDateFormat("yyMMdd");
		return sdf.format(Calendar.getInstance().getTime());
	}

	/**
	 * 如201809
	 * @return
	 */
	public String getYYYYMM() {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyyMM");
		return sdf.format(Calendar.getInstance().getTime());
	}

	/**
	 * 如 2018/02/11
	 * @return
	 */
	public String getQueryEndDate() {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
		return sdf.format(Calendar.getInstance().getTime());
	}

	/**
	 * 如 2018/02/11
	 * @return
	 */
	public String getQueryStartDate() {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
		Calendar cal = Calendar.getInstance();
		cal.add(Calendar.DAY_OF_YEAR, -30);
		return sdf.format(cal.getTime());
	}

	/**
	 * 如 2018/02/11 12:30:00
	 * @return
	 */
	public static String getQueryEndTime() {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		return sdf.format(Calendar.getInstance().getTime());
	}

	/**
	 * 如 2018/02/11
	 * @return
	 */
	public String getQueryStartTime() {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		Calendar cal = Calendar.getInstance();
		cal.add(Calendar.DAY_OF_YEAR, -30);
		return sdf.format(cal.getTime());
	}

	public String getQueryTwoAgoDate() {
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
		Calendar cal = Calendar.getInstance();
		cal.add(Calendar.DAY_OF_YEAR, -2);
		return sdf.format(cal.getTime());
	}

	/**
	 * 字符串转换成日期
	 *
	 * @param str 字符串
	 * @param format 日期格式
	 * @return 日期
	 */
	public static Date str2Date(String str, String format) {
		if (null == str || "".equals(str)) {
			return null;
		}
		// 如果没有指定字符串转换的格式，则用默认格式进行转换
		if (null == format || "".equals(format)) {
			format = DEFAULT_FORMAT;
		}
		SimpleDateFormat sdf = new SimpleDateFormat(format);
		Date date = null;
		try {
			date = sdf.parse(str);
			return date;
		} catch (ParseException e) {
		}
		return null;
	}

	/**
	 * @param date 日期
	 * @param format 日期格式
	 * @return 字符串
	 */
	public static String date2Str(Date date, String format) {
		if (null == date) {
			return null;
		}
		SimpleDateFormat sdf = new SimpleDateFormat(format);
		return sdf.format(date);
	}

	/**
	 * 时间戳转换为字符串
	 * @param time
	 * @return
	 */
	public static String timestamp2Str(Timestamp time) {
		Date date = new Date(time.getTime());
		return date2Str(date, DEFAULT_FORMAT);
	}

	/**
	 * 字符串转换为时间
	 * @param str
	 * @return
	 */
	public static Timestamp str2Timestamp(String str) {
		Date date = str2Date(str, DEFAULT_FORMAT);
		return new Timestamp(date.getTime());
	}

	/**
	 * 字符串转换为时间
	 * @param str
	 * @return
	 */
	public static Timestamp str2Timestamp(String str, String formatStr) {
		if (null == str) {
			return null;
		}
		Date date = str2Date(str, formatStr);
		return new Timestamp(date.getTime());
	}

	/**
	 * 获取某年第一天日期
	 * @param year 年份
	 * @return Date
	 */
	public static Date getYearFirst(int year) {
		Calendar calendar = Calendar.getInstance();
		calendar.clear();
		calendar.set(Calendar.YEAR, year);
		Date currYearFirst = calendar.getTime();
		return currYearFirst;
	}

	/**
	 * 获取某年最后一天日期
	 * @param year  年份
	 * @return Date
	 */
	public static Date getYearLast(int year) {
		Calendar calendar = Calendar.getInstance();
		calendar.clear();
		calendar.set(Calendar.YEAR, year);
		calendar.roll(Calendar.DAY_OF_YEAR, -1);
		Date currYearLast = calendar.getTime();

		return currYearLast;
	}

	@SuppressWarnings("static-access")
	public static Date getnextLast(String datetime, int year) {
		Calendar calendar = new GregorianCalendar();
		Date date = null;
		if (datetime.length() > 7) {
			date = str2Date(datetime, "yyyy-MM-dd");
		} else {
			date = str2Date(datetime, "yyyy-MM");
		}
		calendar.setTime(date);
		calendar.add(calendar.YEAR, year);// 把日期往后增加一年.整数往后推,负数往前移动
		date = calendar.getTime();
		return date;

	}

	public static String getrightDate(String datetime, int year) {
		String date = "";
		String years = datetime.substring(0, 4);
		String dates = datetime.substring(4, datetime.length());
		Integer s = new Integer(years) + year;
		date = s + dates;
		return date;
	}

	public static void main(String[] args) {
		logger.info(getrightDate("2018-09", 4));
		logger.info(date2Str(getnextLast("2018-09", 4), "yyyy-MM"));
	}

}