Java Beginner - Counting number of words in sentence

Question

I am suppose to use methods in order to count number of words in the a sentence. I wrote this code and I am not quite sure why it doesn\'t work. No matter what I write, I on

Answer 1

Please check for boundary conditions at str.charAt(i+1). It can result in a StringIndexOutOfBoundsException when the string is terminated by a space.

1. Account for cases where the string starts with a ' '
2. The String could be blank.
3. The definition of a 'word' could differ. For example - '1 2'. Are 1,2 words ?

I know you do not want an alternate method but string.split(" ").length() is an easier way to start.

Answer 2

i<=str.length()-1 should probably be i<str.length()-1 or you will get an IndexOutOfBoundsException at str.charAt(i+1) (the available values are str.charAt(0) to str.charAt(str.length()-1)).

Answer 3

import java.util.HashMap;

import java.util.Map;

import java.util.Scanner;

public class WordrCount {

public static void main(final String[] args) {
    System.out.println("Please Enter Your String: ");
    final Map<String, Integer> hm = new HashMap<String, Integer>();
    final Scanner sc = new Scanner(System.in);
    final String s1 = sc.nextLine();
    final String[] c1 = s1.split(" ");
    for (int i = 0; i < c1.length; i++) {
        if (!hm.containsKey(c1[i])) {
            hm.put(c1[i], (Integer)1);
        }// if
        else {
            hm.put(c1[i], hm.get(c1[i]) +(Integer) 1);

        }// else
    }// for

    System.out.println("The Total No Of Words: " + hm);

}// main

}// WordCount

Answer 4

class Words {
public static void main(String[] args) {

    String str="Hello World this is new";
    str=str.trim();
    int n=str.length();
    char a[]=new char[n];
    str.getChars(1,n,a,0);
    for (int i=0;i<str.length() ; i++){
        if(a[i]==' ') count++;
    }
    System.out.println("No. of words = "+(count+1));
}

}

Answer 5

This is how i have done it :

It works fine too

    import java.util.Scanner;


    public class countwords {

        public static void main(String args[]){
            Scanner in=new Scanner(System.in);
            System.out.println("Enter your sentence:[Try to ignore space at end]");
            String s=in.nextLine();
            System.out.println("Size of the string is "+s.length());
            int res=count(s);
            System.out.println("No of words in the given String --->>"+"  "+s+" "+"is"+" :"+res);
        }


        private static int count(String s) {
            // TODO Auto-generated method stub
            int count=0;
            if(s.charAt(0)!=' '){
                count++;
            }
            for(int i=0;i<s.length();i++){
                if((s.charAt(i)==' ')){
                    count++;
                }
            }
            return count;
        }


}

OUTPUT: this is my world bonaza

Size of the string is 23

No of words in the given String --->> this is my world bonazais :5

There are some bugs try to correct them and repost

A more simple way that i found was :

Just use this :

    // Read a string
String st=s.nextLine();

// Split string with space
String words[]=st.trim().split(" ");

Answer 6

An easy way to solve this problem:

return str.split(" ").length;

Or to be more careful, this is how you'd take into account more than one whitespace:

return str.split("\\s+").length;