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javaregexcompiler-construction

regex - Java starts with * and ends with a newline (\n)

Basically this is what it looks like:

int abc = 10;
* this is a comment

so, I just want to find the * this is a comment so that I can remove it from the string. I have tried some examples although it doesn't seem to work. The idea is basically starts with * followed by any combination of words, numbers, or symbols (anything really) that ends with a newline (\n).


Thank you.

Solution

  • The pattern ^\*.*$ should work here:

    String line = "Not a comment\n* This is a comment\n*This is also a comment\n";
line += "Not a * comment.";
String pattern = "^\\*.*$";

Pattern r = Pattern.compile(pattern, Pattern.MULTILINE);
Matcher m = r.matcher(line);

while (m.find( )) {
    System.out.println("Found value: " + m.group(0) );
}

Found value: * This is a comment
Found value: *This is also a comment

    Not much to explain here, except that * is a regex metacharacter, and if you want to use it as a literal, then it needs to be escaped by a backslash.

    Demo