无涯教程-Java 正则 - \B匹配函数

边界匹配器 [\B] 匹配非单词边界。

B - 示例

以下示例显示了边界匹配器的用法。

package com.learnfk;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class BoundaryMatcherDemo {
   private static final String REGEX = "\\B";
   private static final String INPUT = "Welcome to LearnFk.COM";

   public static void main(String[] args) {
      //创建一个模式
      Pattern  pattern = Pattern.compile(REGEX);
      
      //获取匹配对象
      Matcher matcher = pattern.matcher(INPUT); 

      while(matcher.find()) {
         //打印匹配的起始索引。
         System.out.println("Match String start(): "+matcher.start());
      }
   }
}

让无涯教程编译并运行以上程序，这将产生以下输出-

Match String start(): 1
Match String start(): 2
Match String start(): 3
Match String start(): 4
Match String start(): 5
Match String start(): 6
Match String start(): 9
Match String start(): 12
Match String start(): 13
Match String start(): 14
Match String start(): 15
Match String start(): 16
Match String start(): 17
Match String start(): 18
Match String start(): 19
Match String start(): 20
Match String start(): 21
Match String start(): 22
Match String start(): 23
Match String start(): 24
Match String start(): 27
Match String start(): 28

参考链接

https://www.learnfk.com/javaregex/javaregex-boundary-matcher-nonword.html