First, please UseCodeTags(⇐click) so that your code will be readable.
Second, note that replaceAll takes a regex as it's input, not just a plain old String. You have at least one character in your input that's special to regex. I'm surprised it's working at all. Either form a proper regex, or use the simple replace() method, which doesn't use regex.
Finally, look at your code, carefully:
What, exactly, do you think the first line will do?
What, exactly, do you think the second line will do?
Imagine you're the JVM, very carefully execute those first two lines with pencil and paper. If you do that correctly, you'll have your answer.
subject: Problem while replacing line with another string