Question

I am trying to parse some lines and check their values, For example in the string:

   " 1 ON OFF";

I have to check whether:

• the first character is blank.
• the second character is int.
• the third character is blank.
• the fourth character is 2 characters and it is ON.
• the fifth character is blank.
• the sixth character is 3 characters and it is OFF.

I can do this at one go using regex, but what I want is that after each check I have to display whether is correct or not like:

   System.out.println("1st character is not a blank : incorrect");
   System.out.println("1st character is blank : correct");

I thought of using Scanner class for this, but when I try to detect the first character, it is showing 1 instead of blank for the string,

   " 1 ON OFF";

   public class NewClass {    

    public void StringExample(){
        String str = " 1 ON OFF";

        Scanner sc = new Scanner(str);
        System.out.println(sc.next());
    }

    public static void main(String args[]){
        NewClass nc = new NewClass();
        nc.StringExample();
    }
}

Is there any other class in java with which this can be done easily?

Answer 1

The closest I can think of is splitting by word boundary:

String tokens[] = " 1 ON OFF".split("\\b");

It will give the following array:

{ " ", "1", " ", "ON", " ", "OFF" }

It fits your ordering and your definition of 1st-6th “character”.