Utils of various date conversion

package com.asiniafo.dpi_new.dpi.utils;


import java.text.SimpleDateFormat;
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.format.DateTimeFormatter;
import java.util.Date;

/**
 *  Date converted utils
 */
public class DateUtil {
    private static SimpleDateFormat sf = null;

    // Convert string to timestamp 
    public static Long timeToLong(String time){
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMddHHmmss");
        LocalDateTime parse = LocalDateTime.parse(time, formatter);
        return LocalDateTime.from(parse).atZone(ZoneId.systemDefault()).toInstant().toEpochMilli();
    }


    // Convert... To time stamp 
    public static String getTimeStampToString(long time){
        Date date = new Date(time);
        sf = new SimpleDateFormat("yyyyMMddHHmmss");
        return sf.format(date);
    }

    // Get the current time 
    public static String getCurrentDate(){
        Date date = new Date();
        sf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        return sf.format(date);
    }

    // Convert string to timestamp 
    public static long getStringToTimeStamp(String time) {
        SimpleDateFormat format = new SimpleDateFormat("yyyyMMddHHmmss");
        Date date = new Date();
        try{
           date = sf.parse(time);
        }catch (Exception e){
            e.printStackTrace();
        }
        return date.getTime();
    }

    // Get the current timestamp directly 
    public static String getTimeStamp(){
        String currentDate = getCurrentDate();
        sf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = new Date();
        try {
            date = sf.parse(currentDate);
        }catch (Exception e){
            e.printStackTrace();
        }
        return String.valueOf(date.getTime());
    }
}