Negative Lookbehind
Negative lookbehind is usually useful if we want to match something not proceeded by something else. We can make our own negative lookbehinds with the lookbehind operator (?<!). For example, to match two characters not proceeded by four digit, we could use :
More Examples
Negative lookbehind After the Match Examples
Program
import java.util.regex.Pattern; import java.util.regex.Matcher; public class Javaapp { public static void main(String[] args) { Pattern pat = Pattern.compile("\\w+\\b(?<!it)"); Matcher mat = pat.matcher("achmit abens aconit admet acquit flees adamit"); while(mat.find()) { System.out.println(mat.group()); } } }