Java示例查找Word出现次数

import java.util.regex.Matcher;

import java.util.regex.Pattern;



public class Main {

   public static void main(String args[]) throws Exception {

      String candidate = "this is a test, A TEST.";

      String regex = "\\ba\\w*\\b";

      Pattern p = Pattern.compile(regex);

      Matcher m = p.matcher(candidate);



      String val = null;

      System.out.println("INPUT: " + candidate);

      System.out.println("REGEX: " + regex + "\r\n");



      while (m.find()) {

         val = m.group();

         System.out.println("MATCH: " + val);

      }

      if (val == null) {

         System.out.println("NO MATCHES: ");

      }

   }

}