Java: Obtain matched string from an input
Question
I am trying to obtain the string that my matcher is able to find using my provided expression. Something like this..
if(matcher.find())
System.out.println("Matched string is: " + ?);
What would be the appropriate code for this? According to Oracle the
matcher.group();
method returns only the provided input same as
matcher.group(0);
Thanks in advance..
Edit:
Example follows below:
private static String fileExtensionPattern = ".*<input type=\"hidden\" name=\".*\" value=\".*\" />.*";
private static Matcher fileXtensionMatcher;
private static String input = text "<html><body><table width="96"><tr><td><img src="file:/test" /><input type="hidden" name="docExt" value=".doc" />Employee Trv Log 2011 Training Trip.doc</td></tr></table></body></html>"
private static void findFileExtension() {
System.out.println("** Searching for file extension **");
System.out.println("Looking for pattern: " + fileExtensionPattern);
fileXtensionMatcher = fileXtensionExp.matcher(input);
if(fileXtensionMatcher.find()) {
//the extension expression is contained in the string
System.out.println("Extension expression found.");
System.out.println(fileXtensionMatcher.group());
}
}
The obtained result is:
text "<html><body><table width="96"><tr><td><img src="file:/test" /><input type="hidden" name="docExt" value=".doc" />Employee Trv Log 2011 Training Trip.doc</td></tr></table></body></html>"
3 answers
solution1
4 2011-09-12 15:37:44
Why do you think that group() returns the input?
According to the JavaDoc :
Returns the input subsequence matched by the previous match.
In other words: it returns that part of the input that was matched.
solution2
3 ACCPTED 2011-09-12 15:52:21
After you added the source code, I can assure you the group() returns the whole input string because it matches your regular expression. If you want just the <input> element use:
private static String fileExtensionPattern = "<input type=\"hidden\" name=\".*\" value=\".*\" />";
Or use:
private static String fileExtensionPattern = ".*(<input type=\"hidden\" name=\".*\" value=\".*\" />).*";
. . .
System.out.println(fileXtensionMatcher.group(1));
solution3
2 2011-09-12 15:52:20
After seeing your update it seems like you need matcher groups. Also you need to make your matches non-greedy ( .*? instead of .* ). Try this:
private static String fileExtensionPattern =
".*<input type=\"hidden\" name=\".*?\" value=\"(.*?)\" />([^<]*)";
// etc.
private static void findFileExtension() {
// etc.
if(fileXtensionMatcher.find()) {
// etc.
System.out.println(fileXtensionMatcher.group(1));
System.out.println(fileXtensionMatcher.group(2));
}
}
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.