How to insert Space after every Character of an existing String in Java?

This will space out all letters in each word and not between words

"Joe Black".replaceAll("\\B", " ") -> "J o e B l a c k"

This will put space for each character (including original spaces)

"Joe Black".replaceAll("\\B|\\b", " ") -> " J o e  B l a c k "

Shorter would be using a regex:

System.out.println("Joe".replaceAll(".(?!$)", "$0 "));

For Android & Kotlin users, if you want to add space after every X characters then use this

val stringWithSpaceAfterEvery4thChar = stringWith12Chars?.replace("....".toRegex(), "$0 ")

Here I added 4 dots in method to add space after every 4th character in my whole string. If you want space after every 2 characters then add only 2 dots in the method.

My variables:

stringWith12Chars = "123456789012"

and the output would be,

stringWithSpaceAfterEvery4thChar = "1234 5678 9012"

Something like:

String joe = "Joe";
StringBuilder sb = new StringBuilder();

for (char c: joe.toCharArray()) {
   sb.append(c).append(" ");
}

System.out.println(sb.toString().trim());