Question

I am using regex to go through some VB code and I want to find statements of the form –

    ABC.Transaction = GlobalCommArea

Unfortunately, some statements are commented out in the code. VB single line comments begin with a single quote, so my search gives results like –

        ' ABCD.Transaction = GlobalCommArea    <-- incorrect
  ' PQR.Transaction = GlobalCommArea           <-- incorrect
  WXY.Transaction = GlobalCommArea             <-- correct
      WXY.Transaction = GlobalCommArea ' 2012      <-- correct

I tried to detect for the presence of a single quote and exclude it, using the following code –

     public static void test2()
     {
    String[] lines = new String[20];

  lines[0] = "' ABCD.Transaction = GlobalCommArea";
  lines[1] = "   ' PQR.Transaction = GlobalCommArea";
  lines[2] = " WXY.Transaction = GlobalCommArea";
  lines[3] = "WXY.Transaction = GlobalCommArea ' 2012";

  String regex;
  regex = "^\\s*[^']*\\s*.*.Transaction\\s*=\\s*GlobalCommArea"; // the regex that I am using

      Pattern p = Pattern.compile(regex);


  for(int i=0; i<=3; i++)
  {
     Matcher m = p.matcher(lines[i]);

     if(m.find())
     {
        System.out.print("Yes\t");
     }
     else
     {
        System.out.print("No\t");
     }

      System.out.println(lines[i]);
     }
    }

However, the regex didn’t work. I got the following output –

    Yes ' ABCD.Transaction = GlobalCommArea
    Yes    ' PQR.Transaction = GlobalCommArea
    Yes  WXY.Transaction = GlobalCommArea
    Yes WXY.Transaction = GlobalCommArea ' 2012

How to write a regex that will detect the single quote at the beginning of the line (i.e. excluding whitespace) and avoid those lines?

Answer 1

You are matching all of them because of the .* before Transaction, try changing it to the following:

regex = "^[^']*\\.Transaction\\s*=\\s*GlobalCommArea";