Java: Help with a RegEx

Question

So, I want to replace all & in the following string with a single &. These & can be separated by one or more spaces. I have a sample input string and a code snippet of what I have.

Input string:

a&   &    &&&  & b  

Here is what I have so far:

String foo = "a&   &    &&& & b".replaceAll("(\\s*&+\\s*&\\s*)", "&");
System.out.println(foo); // prints: "a&&b"
                         // expected: "a&b"

I'm not sure why two & are ending up in the result.

Any hlep would be appreciated. Thanks!

Answer 1

why make it more complicated than it needs to be

"(\\s*&)+\\s*"

one or more (sequences of & preceded by zero or more whitespace) followed by zero or more whitespace

Answer 2

Try:String foo = "a& & &&& & b".replaceAll("(\\s*&[\\s&]*)", "&");