Regex with any character in front and after given string

Question

I've got the following text: Unbekannter Fehler: while trying to invoke the method test() of a null object loaded from local variable 'libInfo'

Matcher matcher = null;
Pattern pattern = null;
try
{
    pattern = Pattern.compile(".*" + "Unbekannter Fehler: while trying to invoke the method test() of a null object loaded from local variable 'libInfo'" + ".*", Pattern.CASE_INSENSITIVE & Pattern.DOTALL);
    matcher = pattern.matcher("Unbekannter Fehler: while trying to invoke the method test() of a null object loaded from local variable 'libInfo'");

    if (matcher.matches())
        System.out.println("Same!");
}

If I run the above code, it returns false , but why? I just want to check, if the text is contained by the other one with regular expression (No String.contains(...) ). If I read it properly, I have to use .* at the beginning and at the end of the regex to be sure, that it neverminds, what is coming in front or after the string to check.

Answer 1

Make sure all of your characters are properly escaped first. Try using Pattern#quote

String test = "Unbekannter Fehler: while trying to invoke the method test() of a null object loaded from local variable 'libInfo'";

Pattern pattern = Pattern.compile(".*" + Pattern.quote(test)  + ".*", Pattern.CASE_INSENSITIVE & Pattern.DOTALL);
Matcher matcher = pattern.matcher(test);

if (matcher.matches()) {
    System.out.println("Same!");
}

Answer 2

You have to quote the parentheses in the pattern.

pattern = Pattern.compile("Unbekannter Fehler: while trying to invoke the method test\\(\\) of a null object loaded from local variable 'libInfo'", Pattern.CASE_INSENSITIVE & Pattern.DOTALL);

You shouldn't need the .* at the beginning, nor the end though.

Regards