How to convert hour in string to minutes in Android

Question

I need help writing "01:16:50" as 76 Minutes in Android.

I have already tried searching with no help.

Answer 1

tl;dr

A simple one-liner:

Duration.between( 
    LocalTime.MIN ,
    LocalTime.parse( "01:16:50" )
)
.toMinutes() 

See this code run live at IdeOne.com.

76

Details

Your input string is unfortunately using time-of-day format rather than the ISO 8601 standard format for durations.

So we must pull a trick in order to decipher your input as a span-of-time rather than a time-of-day.

First we parse the input as a time-of-day, a LocalTime object.

LocalTime lt = LocalTime.parse( "01:16:50" ) ;

Then we calculate elapsed time (Duration) from 00:00 (LocalTime.MIN) to that pretend time-of-day. That effectively gives us the amount of time intended by your input.

Duration duration = Duration.between( LocalTime.MIN , lt ) ;

Lastly, we interrogate that Duration object for its total length as a count of whole minutes.

long minutes = duration.toMinutes() ;

See this code run live at IdeOne.com.

duration: PT1H16M50S

minutes: 76

The above code is in Java syntax. Of course you could do the same in Kotlin syntax. See bullets below about versions of Android.

I recommend you educate the publisher of your data about ISO 8601. Those standard formats are designed for data exchange of date-time values textually while avoiding ambiguity. Your use of time-of-day format for a duration is inherently ambiguous, confusing, and error-prone.

Duration.parse( "PT1H16M50S" ).toMinutes()

---

About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes. Hibernate 5 & JPA 2.2 support java.time.

Where to obtain the java.time classes?

• Java SE 8, Java SE 9, Java SE 10, Java SE 11, and later - Part of the standard Java API with a bundled implementation.
  • Java 9 brought some minor features and fixes.
• Java SE 6 and Java SE 7
  • Most of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport.
• Android
  • Later versions of Android (26+) bundle implementations of the java.time classes.
  • For earlier Android (<26), the process of API desugaring brings a subset of the java.time functionality not originally built into Android.
    • If the desugaring does not offer what you need, the ThreeTenABP project adapts ThreeTen-Backport (mentioned above) to Android. See How to use ThreeTenABP….

Answer 2

Try this:

public class Help{
//method start
public static String convertHoursToMinutes(String time){
    try{
        if(time.charAt(0) == '0' && time.charAt(3) == '0'){
            time = String.valueOf(Integer.parseInt(String.valueOf(time.charAt(1))) * 60 + Integer.parseInt(String.valueOf(time.charAt(4))));
        }else if(time.charAt(0) != '0' && time.charAt(3) == '0'){
            time = String.valueOf(Integer.parseInt(String.valueOf(time.charAt(0)) + String.valueOf(time.charAt(1))) * 60 + Integer.parseInt(String.valueOf(time.charAt(4))));
        }else if(time.charAt(0) == '0' && time.charAt(3) != '0'){
            time = String.valueOf(Integer.parseInt(String.valueOf(time.charAt(1))) * 60 + Integer.parseInt(String.valueOf(time.charAt(3)) + String.valueOf(time.charAt(4))));
        }else if(time.charAt(0) != '0' && time.charAt(3) != '0'){
            time = String.valueOf(Integer.parseInt(String.valueOf(time.charAt(0)) + String.valueOf(time.charAt(1))) * 60 + Integer.parseInt(String.valueOf(time.charAt(3)) + String.valueOf(time.charAt(4))));
        }else{
            System.err.println("ERROR");
        }
    }catch(Exception e){
        System.err.println("ERROR");
    }

    return time;
}
//method end

public static void main(String[] args) {
   System.out.println(convertHoursToMinutes("01:16:50"));
}
}