import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Example {
public static void main(String[] args) {
final String regex = "Subject :\\s*([^*]*(?:\\*(?!\\*{3}end of input\\*{4})[^*]*)*)";
final String string = "Subject :\n\n"
+ "So for example, one field can span any number of lines and then there will be a message similar to\n"
+ "****end of input****\n\n"
+ "It will match anything after the colon until it hits a new line character. This works for almost all of the fields I need to scrape. One however, is a bit more trouble. One of them, the last one I need to scrape (not shown above) will span multiple lines. There's no way to predict how long it will be, but instead I have another predefined piece of text I can use to determine where to stop capturing.";
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