Replace alphabet in a string using replace?

Question

I\'m wondering if I can use string.replace() to replace all alphabets in a string?

String sentence = \"hello world! 722\"
String str = sentence         


        

Answer 1

You replace using regular expressions with String#replaceAll. The pattern [a-zA-Z] will match all lowercase English letters (a-z) and all uppercase ones (A-Z). See the below code in action here.

final String result = str.replaceAll("[a-zA-Z]","@"); 

If you want to replace all alphabetical characters from all locales, use the pattern \p{L}. The documentation for Pattern states that:

Both \p{L} and \p{IsL} denote the category of Unicode letters.

See the below code in action here.

final String result = str.replaceAll("\\p{L}", "@");