Formatting

add white space

public class White {
    string space = System.out.printf("%-15s", str);

}

Use the StringUtils class, it also includes null check

StringUtils.leftPad(String str, int size);

 StringUtils.rightPad(String str, int size);

Format Codes

if you want to pad a string to a certain length with spaces, use something like this:

String padded = String.format("%-20s", str);

In a formatter, " % " introduces a format sequence.
The " - " means that the string will be left-justified (spaces will be added at the end of the string).
The " 20" means the resulting string will be 20 characters long.
The " s" is the character string format code, and ends the format sequence.