import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Example {
public static void main(String[] args) {
final String regex = "^(?!$)M{0,2}(?:M(?=CM(?:XC)?(?:IX)?$))?(?:C(?=M[^CD]*(?:XC)?[^CD]*$))?M?(?:C(?=D[^C]*(?:XC)?[^C]*$))?D?C{0,2}(?:C(?=XC(?:IX)?$))?(?:X(?=C[^X]*(?:IX)?[^X]*$)(?!.*L))?C?(?:X(?=L[^X]*(?:IX)?[^X]*$))?L?X{0,2}(?:X(?=IX$))?(?:I(?=[XV]$))?X?V?I{0,3}$";
final String string = "I\n"
+ "II\n"
+ "XXIX\n"
+ "XXXVIII\n"
+ "IV\n"
+ "XIV\n"
+ "XXXIX\n"
+ "LXXX\n"
+ "XL\n"
+ "CCCXCIX\n"
+ "DCCCXCIX\n"
+ "CDXC\n"
+ "MMMCMIX\n"
+ "MMMCMXCIX\n"
+ "MMMCM\n"
+ "(MMMCM)CMI\n"
+ "(I)";
final Pattern pattern = Pattern.compile(regex);
final Matcher matcher = pattern.matcher(string);
if (matcher.find()) {
System.out.println("Full match: " + matcher.group(0));
for (int i = 1; i <= matcher.groupCount(); i++) {
System.out.println("Group " + i + ": " + matcher.group(i));
}
}
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html