Words with capital letters

[Arthur Donting]

Hey guys
I need to write a program that reads file and prints words that begin with capital letters on the screen.

For example input file is Test.txt which includes this text
Billy Bob is going to visit his aunt Muriel in Washington.

Than the output should be
Billy
Bob
Muriel
Washington

Could someone pleas help me?

[Ernest Friedman-Hill]

Hi,

Welcome to JavaRanch!

Absolutely, we're here to help. We don't like to hand out code, though -- we like to help you figure it out for yourself. So my first question to you is, what do you have so far? If it's nothing, then what are your thoughts about what to do first?

[Arthur Donting]

Well... Here's what I have so far:

import java.io.*;

public class Fifth {
	
	public static void main(String[] args){
		try {
			FileInputStream fin = new FileInputStream("D:\\Test.txt");  
			DataInputStream din = new DataInputStream(fin);  
			BufferedReader br = new BufferedReader(new InputStreamReader(din));  
			String line;  
			             
			while ((line = br.readLine()) != null) {  
			System.out.println(line);
			}
			din.close();
			} catch (Exception e) {}  
		}
}
  

I had few ideas about what to do next.

First one is just to read line, break it into words, and put each word in array. Than just check each word weather its first letter belongs to a set of Capital letters. I had text how to compare sets somewhere so I would still need to separate words and create dynamic array or something like that (because number of words in line is unknown)

Another idea is to create cycle that scans one letter and if it's capital than prints it and keeps on scanning and printing symbol by symbol until it reaches space. After that again, scans one letter and checks weather it's capital or not and so on... I prefer this solution and have an idea how to write a cycle but have no idea how to scan one character in java if it's possible at all...

[Ryan Beckett]

Get the ascii values of the characters and check them against the ascii table.

public class Caps
{
	public static void main(String... args)
	{
		System.out.println(new Caps().hasCapital("Billy"));
		System.out.println(new Caps().hasCapital("billy"));
	}
	boolean hasCapital(String s)
	{
		int ascii = (int)s.charAt(0);
		if(ascii >= 65 && ascii <= 90)
			return true;
		else
			return false;
	}
}

   

[Ernest Friedman-Hill]

Ryan Beckett wrote:Get the ascii values of the characters and check them against the ascii table.

No, please don't do this! First of all, Java doesn't use ASCII, but Unicode; your "capital letters" could be in many different alphabets around the world, not just ASCII. Secondly, the Java libraries provide methods to do these kinds of tests correctly for Unicode. Look at the static method isUpperCase in the java.lang.Character class.

[Arthur Donting]

Guys, I might have something here...

   
import java.io.*;

public class Fifth {
	
	public static void main(String[] args){
		try {
			FileInputStream fin = new FileInputStream("D:\\Test.txt");  
			DataInputStream din = new DataInputStream(fin);  
			BufferedReader br = new BufferedReader(new InputStreamReader(din));  
			String line;
			char c;
			int i=0;
			
			while ((line = br.readLine()) != null) {
					while (i<line.length()){
						c=line.charAt(i);
						if (Character.isUpperCase(c)==true) {
							while (c != ' '){
								System.out.print(c);
								i++;
								c=line.charAt(i);
							}
							System.out.println();
							i++;
						}
						else {
							while (c != ' '){
								i++;
								c=line.charAt(i);
							}
							i++;
						}
					}
			}
			din.close();
			} catch (Exception e) {}  
		}
}
 

It works for me perfectly.
what do you think?

[Ryan Beckett]

Never thought about that, and to think they teach us that in college. Thanks.

[Campbell Ritchie]

You may find a Scanner easier to use than BufferedReader, assuming the file is a text file.
You may find the split method of the java.lang.String class useful, too.

[Moojid Hamid]

Arthur do you know what "regular expressions" are? If you don't have a look at:

http://java.sun.com/docs/books/tutorial/essential/regex/

You can greatly simplify your code by using regular expressions.

[Bauke Scholtz]

There is the Character#isUpperCase().

[Wendy Gibbons]

have you looked at the String.split methods. They will take your input buffer and split it into words and pop the results into an array for you.