DataUtils--判断指定日期是否为今天昨天

package com.zuji.entrance.utils;

import com.tantu.module.common.file.StringUtils;

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

/**
 * Created by fangyc on 2018/7/20.
 */

public class DateUtils {
    /**
     * 判断给定字符串时间是否为今日(效率不是很高，不过也是一种方法)
     * @param sdate
     * @return boolean
     */
//    public static boolean isToday(String sdate){
//        boolean b = false;
//        Date time = toDate(sdate);
//        Date today = new Date();
//        if(time != null){
//            String nowDate = dateFormater2.get().format(today);
//            String timeDate = dateFormater2.get().format(time);
//            if(nowDate.equals(timeDate)){
//                b = true;
//            }
//        }
//        return b;
//    }

    /**
     * 将字符串转位日期类型
     *
     * @param sdate
     * @return
     */
    public static Date toDate(String sdate) {
        try {
            return dateFormater.get().parse(sdate);
        } catch (ParseException e) {
            return null;
        }
    }

    private final static ThreadLocal<SimpleDateFormat> dateFormater = new ThreadLocal<SimpleDateFormat>() {
        @Override
        protected SimpleDateFormat initialValue() {
            return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        }
    };

    private final static ThreadLocal<SimpleDateFormat> dateFormater2 = new ThreadLocal<SimpleDateFormat>() {
        @Override
        protected SimpleDateFormat initialValue() {
            return new SimpleDateFormat("yyyy-MM-dd");
        }
    };
    private static ThreadLocal<SimpleDateFormat> DateLocal = new ThreadLocal<SimpleDateFormat>();

    /**
     * 判断是否为今天(效率比较高)
     *
     * @param day 传入的 时间  "2016-06-28 10:10:30" "2016-06-28" 都可以
     * @return true今天 false不是
     * @throws ParseException
     */
    public static boolean IsToday(String day) throws ParseException {

        Calendar pre = Calendar.getInstance();
        Date predate = new Date(System.currentTimeMillis());
        pre.setTime(predate);

        Calendar cal = Calendar.getInstance();
        Date date = getDateFormat().parse(day);
        cal.setTime(date);

        if (cal.get(Calendar.YEAR) == (pre.get(Calendar.YEAR))) {
            int diffDay = cal.get(Calendar.DAY_OF_YEAR)
                    - pre.get(Calendar.DAY_OF_YEAR);

            if (diffDay == 0) {
                return true;
            }
        }
        return false;
    }

    /**
     * 判断是否为昨天(效率比较高)
     *
     * @param day 传入的 时间  "2016-06-28 10:10:30" "2016-06-28" 都可以
     * @return true今天 false不是
     * @throws ParseException
     */
    public static boolean IsYesterday(String day) throws ParseException {

        Calendar pre = Calendar.getInstance();
        Date predate = new Date(System.currentTimeMillis());
        pre.setTime(predate);

        Calendar cal = Calendar.getInstance();
        Date date = getDateFormat().parse(day);
        cal.setTime(date);

        if (cal.get(Calendar.YEAR) == (pre.get(Calendar.YEAR))) {
            int diffDay = cal.get(Calendar.DAY_OF_YEAR)
                    - pre.get(Calendar.DAY_OF_YEAR);

            if (diffDay == -1) {
                return true;
            }
        }
        return false;
    }

    public static SimpleDateFormat getDateFormat() {
        if (null == DateLocal.get()) {
            DateLocal.set(new SimpleDateFormat("yyyy-MM-dd", Locale.CHINA));
        }
        return DateLocal.get();
    }

    public static String TodayOrYesterday(String day) throws ParseException {
        String dayStr;
        Calendar pre = Calendar.getInstance();
        Date predate = new Date(System.currentTimeMillis());
        pre.setTime(predate);

        Calendar cal = Calendar.getInstance();
        Date date = getDateFormat().parse(day);
        cal.setTime(date);

        if (cal.get(Calendar.YEAR) == (pre.get(Calendar.YEAR))) {
            int diffDay = cal.get(Calendar.DAY_OF_YEAR)
                    - pre.get(Calendar.DAY_OF_YEAR);
            if (diffDay == 0) {
                dayStr = "今天";
            } else if (diffDay == -1) {
                dayStr = "昨天";
            } else {
                String[] str = day.split("-");
                dayStr = str[1] + "月" + str[2] + "日";
            }
        } else {
            String[] str = day.split("-");
            dayStr = str[1] + "月" + str[2] + "日";
        }
        return dayStr;
    }

}

感谢：
android 判断指定日期是否为今天昨天