最近积累的一些工具方法（2019-06-12）

 /**
 * 获取当前时间往前往后推几天
 *
 **/
 public Map<String,Date> getDate() {
        Map<String,Date> map = new HashMap<>(2);
        try {
            //获取当前日期
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
            Date today = new Date();
            Date endDate = sdf.parse(sdf.format(today));
            //获取三十天前日期
            Calendar theCa = Calendar.getInstance();
            theCa.setTime(today);
            //最后一个数字5可改，5天的意思
            //data就是往前往后几天的意思，负数是往前，正数是往后
            theCa.add(Calendar.DATE, Integer.parseInt(date));
            Date start = theCa.getTime();
            //三十天之前日期
            Date startDate = sdf.parse(sdf.format(start));
            map.put("end",endDate);
            map.put("start",startDate);
        } catch (ParseException e) {
            e.printStackTrace();
            log.error(e);
        }
        return map;
    }


     /**
     * @param firstArrayList  第一个ArrayList
     * @param secondArrayList 第二个ArrayList
     * @return resultList 差集ArrayList
     * @方法描述：获取两个ArrayList的差集
     */
    public static List<IncomeInvResponse> receiveDefectList(List<IncomeInvResponse> firstArrayList,
            List<InvoiceDetailDO> secondArrayList) {
        List<IncomeInvResponse> resultList = firstArrayList.stream()
                .filter(item -> !secondArrayList.stream().map(e -> e.getInvoiceCode() + "|" + e.getInvoiceNum())
                        .collect(Collectors.toList()).contains(item.getInvoiceCode() + "|" + item.getInvoiceNr()))
                .collect(Collectors.toList());
        return resultList;
    }



     /**
     * 计算两个时间相差天数
     * @param date1
     * @param date2
     * @return
     */
    public static int differentDaysByMillisecond(Date date1, Date date2) {
        int days = (int) ((date2.getTime() - date1.getTime()) / (1000*3600*24));
        return days;
    }

    /**
     * 解析字符串中的数字和汉字
     * @param str
     * @return
     */
    public static Map<String,String> getChinaNum(String str) {
        Map<String,String> obj = new HashMap<>();
        if(StringUtils.isEmpty(str)){
            return obj;
        }
        //获取数字
        String a = str.replaceAll("[^0-9-]", "_").replace("_+", "_");
        String[] as = a.split("_+");
        obj.put("num",replaceNull(as));
        //获取汉字
        String b = str.replaceAll("[^\\u4e00-\\u9fa5]", "_").replace("_+", "_");
        String[] bs = b.split("_+");
        obj.put("china",replaceNull(bs));
        return obj;
    }

    /**
     * 去除数组中的空串
     * @param str
     * @return
     */
    public static String replaceNull(String[] str){
        StringBuffer sb = new StringBuffer();
        for(int i=0; i<str.length; i++) {
            if("".equals(str[i])) {
                continue;
            }
            sb.append(str[i]);
            if(i != str.length - 1) {
                sb.append(",");
            }
        }
        return sb.toString();
    }