Is there a library function that can give me the current date in variables and find the number of days passed since a given date

Question

I want to get the current date and time the variables

 int d,m,y,h,s;

So far I have made a class for Date that could let the user enter the date and it checks for the validity of the date but I am not sure how to get the number of days passed since and also the current date.

My class Date ->

import ShortHand.*;
public class Date {
    public static char[] digits={'0','1','2','3','4','5','6','7','8','9'};
    int d=0,m=0,y=0;
    public int getD() {
        return d;
    }
    public int getM() {
        return m;
    }
    public int getY() {
        return y;
    }
    public Date(int dd,int mm,int yy)
    {
        if (checkDate(dd,mm,yy)==false)
            throw new IllegalArgumentException("Invalid Date");
        this.d=dd;
        this.m=mm;
        this.y=yy;
    }   
    public static boolean checkDate(int d,int m,int y)
    {
        if (m<1||d<1||y<1)
            return false;
        if (m>12)
            return false;
        if (m==2&&checkLeap(y)&&d>29)
            return false;
        if (m==2&&!(checkLeap(y))&&m>28)
            return false;
        if ((m==1||m==3||m==5||m==7||m==8||m==10||m==12)&&d>31)
            return false;
        if ((m==4||m==6||m==8||m==11)&&d>30)
            return false;
        return true;
    }
    public static boolean checkLeap(int y)
    {
        if (y%100!=0)
        {
            if (y%4==0)
                return true;
        }
        else if (y%400==0)
            return true;
        return false;
    }
    public static Date takeIn(String msg)throws java.io.IOException
    {
        int d,m,y;
        while(true)
        {
            boolean f=true;
            u.pln(msg+"[dd-mm-yyyy]");
            String in=u.iBs();
            if (in.length()!=10)
            {
                u.pln("Please Enter a Valid Date");
                continue;
            }
            for (int i=0;i<10;i++)
            {
                if (i!=2&&i!=5)
                {
                    if (Arr.check(in.charAt(i), digits)==false)
                    {
                        u.pln("Invalid Input");
                        f=false;
                        break;
                    }
                }
            }
            if (f==false)
                continue;
            String t=in.substring(0,2);
            d=Integer.parseInt(t);
            t=in.substring(3,5);
            m=Integer.parseInt(t);
            t=in.substring(6);
            y=Integer.parseInt(t);
            if (checkDate(d,m,y))
                break;
        }
        return new Date(d,m,y);
    }
    @Override
    public String toString() {
        return this.d+"/"+this.m+"/"+this.y;
    }
    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        Date other = (Date) obj;
        if (d != other.d) {
            return false;
        }
        if (m != other.m) {
            return false;
        }
        if (y != other.y) {
            return false;
        }
        return true;
    }
}

u.pln() is a function made by me which prints the given String to the console and also adds it a String allowing me to write the whole output to a file at the end of execution — Akhand Yaduvanshi, Dec 30 '16 at 06:52

Zbynek Vyskovsky - kvr000 · Answer 1 · 2016-12-30T15:59:06.980

4

There is LocalDate class in Java 8 which will do the difference (and much more):

LocalDate start = LocalDate.of(startYear, startMonth, startDay);
LocalDate end = LocalDate.of(endYear, endMonth, endDay);
long diff = start.until(end, ChronoUnit.DAYS);

To assign the current date into end use now() method:

 LocalDate end = LocalDate.now();

edited Dec 30 '16 at 15:59

answered Dec 30 '16 at 06:55

Zbynek Vyskovsky - kvr000

18,186
3
35
43

Vyskovsky kvr000 How will I get the current date using this class(or any other) – Akhand Yaduvanshi Dec 30 '16 at 06:59
you can use following code to get current date in any format DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss"); Date date = new Date(); System.out.println(dateFormat.format(date)); – Pradnyarani Dec 30 '16 at 07:17
@Pradnyarani what package is class DateFormate and Date in – Akhand Yaduvanshi Dec 30 '16 at 07:23
java.text.DateFormat; java.util.Date; – Pradnyarani Dec 30 '16 at 07:24
Thanks for the help – Akhand Yaduvanshi Dec 30 '16 at 08:07
1

@Pradnyarani That's the old API, which is completely different from what is suggested in this answer. – assylias Dec 30 '16 at 09:14
2

@AkhandYaduvanshi to get the current date: `LocalDate.now()` - don't use the Date / SimpleDateFormat classes if you have a choice. – assylias Dec 30 '16 at 09:14
1

@Pradnyarani: would you consider giving your own answer, rather than adding code to comments? – halfer Dec 30 '16 at 09:36
@AkhandYaduvanshi : I updated the answer with how to get current date. – Zbynek Vyskovsky - kvr000 Dec 30 '16 at 16:00

score 0 · Answer 2 · answered Dec 30 '16 at 09:42

0

To get current date you can use Java 8 Date Time API

DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyy/MM/dd"); 
LocalDate localDate = LocalDate.now(); 
System.out.println(dtf.format(localDate));

answered Dec 30 '16 at 09:42

Pradnyarani

302
1
8

Is there a library function that can give me the current date in variables and find the number of days passed since a given date

2 Answers2