Remove a specific space in a string

Question

I’m having trouble implementing replace in a String in Android Studio.

I need to remove a certain blank in the String.

Real examples:

• 8 hrs 2 mins
• 1 day 2 mins

I need the text to look like this:

• 8hrs 2mins
• 1day 2mins

If anyone can help me, I’d appreciate it.

Answer 1

String comEspaco = "8 hrs 2 mins";
String semEspaco = comEspaco.replace(" hr", "hr").replace(" min", "min");

Alternative solution with regex without depending on what comes after each space:

String comEspaco = "8 hrs 2 mins";
String semEspaco = comEspaco.replaceAll("([0-9]) ", "$1");

See working on Ideone.

Answer 2

String comEspaco = "8 hrs 2 mins";
String semEspaco;

if (comEspaco.constains("hrs")){
    semEspaco = comEspaco.replace(" hrs", "hrs").replace(" mins", "mins")
} else{
    semEspaco = comEspaco.replace(" dia", "dia").replace(" hrs", "hrs")
}

Answer 3

One possible way is to use a Stringbuffer and use the method replace():

String hora = "8 hrs 2 mins";
int firstSpace = hora.indexOf(" ");
int lastSpace = hora.lastIndexOf(" ");
StringBuffer buf = new StringBuffer(hora);

buf.replace(firstSpace, firstSpace + 1, "");
buf.replace(lastSpace-1, lastSpace, "");//Note que após o replace anterior o buffer tem menos um caracter

System.out.println(buf.toString());

See working on Ideone

Another way using subString()

Declare a method that replaces at a given position:

public static String replaceCharAt(String s, int pos, String c) {
    return s.substring(0, pos) + c + s.substring(pos + 1);
}

Use it as follows:

String hora = "8 hrs 2 mins";
int firstSpace = hora.indexOf(" ");

String temp = replaceCharAt(hora, firstSpace, "");

int lastSpace = temp.lastIndexOf(" ");
String horaSemEspacos = replaceCharAt(temp, lastSpace, "");

System.out.println(horaSemEspacos);

See working on Ideone

Answer 4

As you said the format can be varied ( min, mins, miNs, etc...) I will post another way of doing considering the spaces and not the words.

You can use the class Scanner for this, the staff only remembers her to do reading with System.in but it has several useful resources. Scanner#next() returns the next input token and these tokens are by default separated by spaces.

If the input format is always the one you posted, then you can use next() + next() to pick up the tokens two by two. It would look like this:

TOKENS:        8      |   hrs    |    2    |   mins

               ^           ^          ^         ^
               |           |          |         |
               |           |          |         |
CHAMADAS:    next()  +   next()  |  next()  +  next()

                     ^                      ^
                     |                      |

RESULTADO:          8hrs         |        2mins

I made a method with this logic:

public String format(String string){
   Scanner scanner = new Scanner(string);
   StringBuilder sb = new StringBuilder();
   while(scanner.hasNext())
      sb.append(scanner.next())
        .append(scanner.next())
        .append(" ");
   return sb.toString();
}

And in the tests the results were:

String test1 = "50 min";
String test2 = "20 hrs 50 mins";
String test3 = "1 d 20 hrs 50 min";
String test4 = "3 meses 15 dias 20 horas 50 minutos";

System.out.println(format(test1)); // 50min 
System.out.println(format(test2)); // 20hrs 50mins 
System.out.println(format(test3)); // 1d 20hrs 50min 
System.out.println(format(test4)); // 3meses 15dias 20horas 50minutos 

Online example