1. Write a program to echo all command-line arguments to System.out, i.e.,

$ java EchoAll This is a long line

args[0] is This

args[1] is is

args[2] is a

args[3] is long

args[4] is line

1. Complete the "quick-and-dirty" class CharacterCounter containing only a main() method that displays the number of non-space characters on the command line after the command. For example:

$ java CharacterCounter

0

$ java CharacterCounter a

1

$ java CharacterCounter a bc def ghij

10

public class CharacterCounter { 
   public static void main( String[] args ) { 
      int characterCount = 0 ; 











   } // end main 
} // end class CharacterCounter 

2. How would file I/O help improve the capabilities of the MemoPadApp?

// File: Echo.java - Echoes all the words in one file to an output file, one per line. 
import java.io.*; 
import java.util.StringTokenizer; 
public class Echo { 

   public static void main( String[] args ) throws IOException { 
      String delimiters = " .?!()[]{}|?/&\\,;:-\'\"\t\n\r"; 
      BufferedReader inputFile = new BufferedReader( new FileReader( args[0] ) ); 
      PrintWriter outputFile = new PrintWriter( new FileWriter( args[1] ) ); 
      String buffer = null; 

      while( true ) { 
         buffer = inputFile.readLine(); 
         if ( buffer == null ) break; 
         buffer = buffer.toLowerCase(); 
         StringTokenizer tokens = new StringTokenizer( buffer, delimiters ); 

         while( tokens.hasMoreElements() ) { 
            String word = tokens.nextToken(); 
            outputFile.println( word ); 
         } // end while 

      } // end while(true)... 

   } // end main 
} // end class Echo 

3. Add code to Echo.java to create a WordCount.java program that does the same thing as wc, i.e., prints the number of lines, words, and characters in a file to standard output. For example:

$ java WordCount hamlet.txt

lines = 4792 words = 32889 characters = 130156