import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Example {
public static void main(String[] args) {
final String regex = "(?!^)(?<!\\d[.A-Z])(?<!\\d[A-Z]\\.)\\b(?=\\d+(?:[a-zA-Z]|\\.)\\s+\\p{Lu})";
final String string = "5. SCOPE This document outlines what to do in case of emergency landing (ignore for non-emergency landings) on tarmac. 6. WHEELS Never land on tarmac. Unless you have lowered the plane wheel mechanism. 6.1 Lower the wheel mechanism using the 2 Switches labelled 'wheel mechanism'. 7A WARNING 7A.1 Do not forget to warn passengers.\n";
final String subst = "\\n-----------\\n";
final Pattern pattern = Pattern.compile(regex);
final Matcher matcher = pattern.matcher(string);
// The substituted value will be contained in the result variable
final String result = matcher.replaceAll(subst);
System.out.println("Substitution result: " + result);
}
}
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