String formatter IF the value is less than 10 add the leading zeros java in HH:MM:SS format with 3 variables syntax

Question

I cannot find the proper syntax for a string format as well as setting it up for a output that adds the leading zeros IF the value inputted is less than 10.

Assume we are using a scanner to allow a user to input any value they want.

I want the output string to display the hours minutes and seconds in HH:MM:SS with leading zeros if the value for any of variables entered is less than zero

Here is just a main method driver separate from entire main program as I am keeping code quarantined so that I don't get confused:

public class testString {
public static void main(String[] args)
    {
// variables assume that i am allowing scanner input, in main project, for now using 
 // dummy values in place of scanner
        int hours = 1;
        int minutes = 6;
        int seconds = 40;

   // format string to be corrected as well with allowing leading zeros if value is less 
 // than 10
     String output = String.format("%02d %02d %02", hours, minutes,
        seconds);
        System.out.println(output);
    }
}

Answer 1

You forgot the last d . Do it like this. To ensure the field has leading zeros, put a 0 before the width specifier.

      String output = String.format("%02d:%02d:%02d", hours, minutes,
                seconds);
      System.out.println(output);

You can also do this by use the System.out.printf() method.

      System.out.printf("%02d:%02d:%02d%n", hours, minutes,
                seconds);

For details, check out Formatter in the Java API.

Answer 2

I cannot find the proper syntax for a string format as well as setting it up for a output that adds the leading zeros IF the value inputted is less than 10.

Assume we are using a scanner to allow a user to input any value they want.

I want the output string to display the hours minutes and seconds in HH:MM:SS with leading zeros if the value for any of variables entered is less than zero

Here is just a main method driver separate from entire main program as I am keeping code quarantined so that I don't get confused:

public class testString {
public static void main(String[] args)
    {
// variables assume that i am allowing scanner input, in main project, for now using 
 // dummy values in place of scanner
        int hours = 1;
        int minutes = 6;
        int seconds = 40;

   // format string to be corrected as well with allowing leading zeros if value is less 
 // than 10
     String output = String.format("%02d %02d %02", hours, minutes,
        seconds);
        System.out.println(output);
    }
}