Padding Strings Seamlessly in Java

Question:

Java lacks an explicit utility for string padding. How can this task be effectively accomplished?

Answer:

Introduced in Java 5, String.format() offers a comprehensive solution for padding strings:

Left-Padding:

public static String padLeft(String s, int n) {
    return String.format("%"   n   "s", s);
}

Right-Padding:

public static String padRight(String s, int n) {
    return String.format("%-"   n   "s", s);
}

Sample Usage:

public static void main(String args[]) throws Exception {
    System.out.println(padRight("Howto", 20)   "*");
    System.out.println(padLeft("Howto", 20)   "*");
}

Output:

Howto               *
               Howto*