Having difficultly in figuring out the working of split function in java

Question

The String i want to split is " He is a very very good boy, isn't he? ". When i used only the split function the out put also printed the space after "boy," in the string. To remove that i put an if condition in the code and then the code doesn't print anything after boy .

Can someone tell me why this is happening ? Also if there is a better way to solve this problem other than using Guava .

public class Solution {


    public static void main(String[] args) 
    {


      Scanner scan = new Scanner(System.in);
      String s=scan.nextLine();

      String []tokens = s.trim().split("[\\s,'?]");
      int n = tokens.length;
        System.out.println(n);
      for(int i=0;i<tokens.length;i++)
      {
          if(tokens[i].charAt(0)==' ')
          {
             continue;
          }

          System.out.println(tokens[i]);
       }

    }
}

Answer 1

You're telling split to split on a single character from that list. If you want it to split on one or more (eg, runs of those characters), add + after it to say "one or more of the thing before":

String []tokens = s.trim().split("[\\s,'?]+");
// Here ----------------------------------^

Live Example

(FWIW, including ' on the list of characters to split on seems a bit odd, but we don't know your use case, so...)

Answer 2

check this solution.

  String str="He is a very very good boy, isn't he?";
       String[] Val = str.split("[' ,@!_.?]+");
       System.out.println(Val.length);
       for(String token :Val) {
              System.out.println(token);}}