Using special chars in RegEx causes problems

Question

Hello Folks,
I have a single string of numbers positive and negative separated by a delimiter. I am trying to convert the negative numbers which are represented by brackets into ones without brakcets e.g. (1.235) to -1.235
Here is what I have in my code
               arCols[j].replaceAll("\(", "-");
               arCols[j].replaceAll("\)", "");
But that gives a compilation problem as below.
Exception in thread "main" java.lang.Error: Unresolved compilation problem:
     Invalid escape sequence (valid ones are \b \t \n \f \r \" \' \\ )
And if I remove the leading slash that tries to escape the character as below
               arCols[j].replaceAll("(", "-");
               arCols[j].replaceAll(")", "");
I get the following error.
Exception in thread "main" java.util.regex.PatternSyntaxException: Unclosed group near index 1
How can I replace the brackets using regular expression search and replace?
Thanks for your help.
Sanjay.

Answer 1

You need
arCols[j] = arCols[j].replaceAll("\\(", "-");
arCols[j] = arCols[j].replaceAll("\\)", "");because
a) String objects are immutable
and b) you need to escape the '(' and ')' .
P.S. With a bit of thought this could be done in one single regex
System.out.println("fasdf(123.4)faf fdf(246.8) fafasd 1.23".replaceAll("\\(([^\\)]*)\\)","-$1"));Edited by: sabre150 on Oct 2, 2007 7:32 AM