Question

I have a string for e.g.

String src = "How are things today /* this is comment *\*/ and is your code  /*\* this is another comment */ working?"

I want to remove /* this is comment *\*/ and /** this is another comment */ substrings from the src string.

I tried to use regex but failed due to less experience.

Answer 1

Try using this regex (Single line comments only):

String src ="How are things today /* this is comment */ and is your code /* this is another comment */ working?";
String result=src.replaceAll("/\\*.*?\\*/","");//single line comments
System.out.println(result);

REGEX explained:

Match the character “/” literally

Match the character “*” literally

“.” Match any single character

“*?” Between zero and unlimited times, as few times as possible, expanding
as needed (lazy)

Match the character “*” literally

Match the character “/” literally

Alternatively here is regex for single and multi-line comments by adding (?s):

//note the added \n which wont work with previous regex
String src ="How are things today /* this\n is comment */ and is your code /* this is another comment */ working?";
String result=src.replaceAll("(?s)/\\*.*?\\*/","");
System.out.println(result);

Reference:

• https://www.regular-expressions.info/examplesprogrammer.html