Need help with a program

[erekose666]

I am totally lost here. I need a program to do the following:

write an application that reads a line of text, tokenizes the line using space characters as delimiters and outputs only those words beginning with the letter "b"

I know how to count tokens and whatnot but how the heck do i print out only toeksn beginning with a certain char?

HELP! :)

[erekose666]

This is the code I have thus far btw:

import java.io.*;
import java.util.*;


public class TokenTest
{
// execute application
public static void main( String args[] )
{
// get sentence
Scanner scanner = new Scanner( System.in );
System.out.prin tln( "Enter a sentence and press Enter" );
String sentence = scanner.nextLin e();

// process user sentence
StringTokenizer tokens = new StringTokenizer ( sentence);
System.out.prin tf( "Number of elements: %d\nThe tokens are:\n",
tokens.countTok ens() );

while ( tokens.hasMoreT okens() )
System.out.prin tln( tokens.nextToke n( ) );
} // end main
} // end class TokenTest

[erekose666]

I am assuming you have to do something with the charAt function, but I have no idea how to implement it within the program.

[r035198x]

I am assuming you have to do something with the charAt function, but I have no idea how to implement it within the program.

for any string s, s.charAt(0) will return the first character of that String

eg String s = "bless";
s.charAt(0) == 'b' will return true

you could also tokenize the string without using the StringTokenizer

String [] tokens = s.split(" ");

[erekose666]

OK so let's assume I'm going to use StringTokenizer . How would I fit this into the program as I have coded it thus far?

[erekose666]

Let me rephrase....I need to return any token that starts with the letter "b", not just the letter "b" itself. :) So from what I'm seeing that you're saying, charAt isn't going to help me at all. Now I'm even more confused than ever lol.

[r035198x]

Let me rephrase....I need to return any token that starts with the letter "b", not just the letter "b" itself. :) So from what I'm seeing that you're saying, charAt isn't going to help me at all. Now I'm even more confused than ever lol.

//You misunderstood my post
import java.io.*;
import java.util.*;
public class TokenTest {

	public static void main( String args[] ) {


		Scanner scanner = new Scanner( System.in );
		System.out.println( "Enter a sentence and press Enter" );
		String sentence = scanner.nextLine();
		int index = 0;

		String [] tokens = sentence.split(" ");
		String [] bstart = new String[tokens.length];

		System.out.println( "The tokens starting with b are: ");
		for(int i = 0; i < tokens.length; i++) {
			if(tokens[i].charAt(0) == 'b')
				bstart[index++] = tokens[i];
		}

		/*
		OR

		StringTokenizer st = new StringTokenizer(sentence);
		while(st.hasMoreTokens()) {
			String s = st.nextToken();
			if(s.charAt(0) == 'b') {
				bstart[index++] = s;
			}

		*/

		for(int i = 0; i < bstart.length; i++) {
			System.out.println(bstart[i]);
		}
		//The problem is the null values appended to fill in the array
	}
}

[erekose666]

OK sorry I did indeed misunderstand :)
That definitely helps me out a lot :)
Thanks so much!

[r035198x]

OK sorry I did indeed misunderstand :)
That definitely helps me out a lot :)
Thanks so much!

If you learn a bit of your regular expressions, you can split the string so that you get only tokens that start with a b.