I can't find any good resource for parsing with regular expression. Could someone please show me the way.
How can I parse this statement?
"Breakpoint 10, main () at file.c:10"
I want get the substring "main ()" or 3rd word of the statement.
6 Answers
This works:
public void test1() {
String text = "Breakpoint 10, main () at file.c:10";
String regex = ",(.*) at";
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(text);
while (matcher.find()) {
System.out.println(matcher.group(1));
}
}
Basically the regular expression .(.*) at with group(1) returns the value main ().
Comments
Assuming you want the 3rd word of your string (as said in your comments), first break it using a StringTokenizer. That will allow you to specify separator (space is by default)
List<String> words = new ArrayList<String>();
String str = "Breakpoint 10, main () at file.c:10";
StringTokenizer st = new StringTokenizer(str); // space by default
while(st.hasMoreElements()){
words.add(st.nextToken());
}
String result = words.get(2);
That returns main
If you also want the (), as you defined spaces as separator, you also need to take the next word words.get(3)
Comments
- Good website regular-expressions.info
- Good online tester regexpal.com
- Java http://download.oracle.com/javase/tutorial/essential/regex/
I turn to these when I want to play with Regex
Comments
Have you seen the standard Sun tutorial on regular expressions ? In particular the section on matching groups would be of use.
Comments
Try: .*Breakpoint \d+, (.*) at
Comments
Well, the regular expression main \(\) does parse this. However, I suspect that you would like everything after the first comman and before the last "at": ,(.*) at gives you that in group(1) that is opened by the parenthesis in the expression.
main()or any method name that could possibly contain parameters as well? Anyways, regular-expressions.info has a good regex reference and quite some tutorials (even Java specific ones).