Comparing SimpleDateFormat output with number

Question

I am making a program that executes something every time the time reaches an hour.

Here is the code:

import java.text.*;
import java.util.Date;
class NMAP {
 public static void main(String[] args) {
  DateFormat dateFormat = new SimpleDateFormat("HH");
  Date date = new Date();
  if (dateFormat.format(date).equals(17)) {
   System.out.println(dateFormat.format(date));
  }
 }
}

It should be outputting 17 (since it is 17:00), but it doesn't output anything.

Why not?

Try `equals("17")`, or you are comparing a `String` with an `Integer` . — Arnaud, Jun 06 '17 at 07:56
17 gets auto-boxed to an Integer object with value 17. For the rest, see the duplicated question. — GhostCat, Jun 06 '17 at 08:02

score 3 · Accepted Answer · answered Jun 06 '17 at 07:59

you are comparing dateFormat.equals(17) a string against an integer

that returns false no matter what because they are different types.

you have to do dateFormat.equals("17")

And because some when you will need the power of java8:

LocalTime now = LocalTime.now();
System.out.println(now);
System.out.println(now.getHour() == 17);

Comparing SimpleDateFormat output with number

1 Answers1