Need assistance with java morse code translator only translating one symbol

Question

I just made a java morse code translator but when i convert morse to english it converts each symbol as a letter so when i as it to translate .... it gives me e e e e instead of h. So my question is how do i make it so i can translate whole words in morse code and use a | to separate words.

here is my code

public class project1 {

public static void main ( String [] args ) {

char [] english = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0' };

String [] morse = { ".-" , "-..." , "-.-." , "-.." , "." , "..-." , "--." , "...." , ".." , ".---" , "-.-" , ".-.." , "--" , "-." , "---" , ".--." , "--.-" ,  ".-." , "..." , "-" , "..-" , "...-" , ".--" , "-..-" , "-.--" , "--.." , "|" };
    String a = Input.getString ( "Please enter MC if you want to translate Morse Code into English, or Eng if you want to translate from English into Morse Code" );
if (a.equals("MC"))
    {
        String b = Input.getString ("Please enter a sentence in Morse Code. Separate each letter/digit with a single space and delimit multiple words with a | .");    

        String[] words = b.split("|");
        for (String word: words )
        {
            String[] characters = word.split(" ");
            for (String character: characters) 
            {
                if (character.isEmpty()) { continue; }
        for (int m = 0; m < morse.length; m++)
                {
                    if (character.equals(morse[m]))    
                        System.out.print(english[m]);    
                }    
            }
            System.out.print(" ");    
        }    
    }
else if (a.equals("Eng"))
    {
        String c = Input.getString ( "Please enter a sentence in English, and separate each word with a blank space." );

        c = c.toLowerCase ();

        for ( int x = 0; x < english.length; x++ )
        {
            for ( int y = 0; y < c.length (); y++ )
            {
                if ( english [ x ] == c.charAt ( y ) )

                System.out.print ( morse [ x ] + "  " );


            }

        }


    }

    else 
   {
       System.out.println ( "Invalid Input" );

    }

}
}

score 0 · Answer 1 · edited May 23 '17 at 11:43

A problem you're having is that your String#split(...) method is not taking into account that | is a special character with regard to regular expressions and is not splitting the String as you would expect. You need to escape this character for things to work right. So change this:

String[] words = b.split("|");

to this:

String[] words = b.split("\\|"); // escaping the pipe char

To debug and to see if things are working as expected, use a debugger or sprinkle println's in your code like:

 String[] words = b.split("\\|");

 // TODO: remove line below from finished program
 System.out.println(java.util.Arrays.toString(words));

As an aside, if this were my program, I'd use HashMap<String, String> to assist with my translation of English to Morse and visa-versa.

On further searching that I just performed, please check out: Why does String.split need pipe delimiter to be escaped? for background information on why the pipe char needs to be escaped.

this did not solve the problem of java only seeing each dot and dash as indivigeuals — asdjhfasdf asdkjfhasjkdfh, May 30 '15 at 21:41
@eliwinston: add the debug code I've suggested at several locations in your morse-to-english code -- see what's going on inside your program as it's running, show us your input text and your debug output, since the changes worked fine for me. — Hovercraft Full Of Eels, May 30 '15 at 21:43

score -1 · Answer 2 · answered May 30 '15 at 20:33

This is your adapted code, which works correctly...

import java.util.Scanner;

public class project1 {

public static void main ( String [] args ) {

char [] english = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0' };

String [] morse = { ".-" , "-..." , "-.-." , "-.." , "." , "..-." , "--." , "...." , ".." , ".---" , "-.-" , ".-.." , "--" , "-." , "---" , ".--." , "--.-" ,  ".-." , "..." , "-" , "..-" , "...-" , ".--" , "-..-" , "-.--" , "--.." , "|" };

Scanner scanner = new Scanner(System.in);
System.out.println("Please enter MC if you want to translate Morse Code into English, or Eng if you want to translate from English into Morse Code");
String a = scanner.nextLine();

if (a.equals("MC"))
    {
        System.out.println("Please enter a sentence in Morse Code. Separate each letter/digit with a single space and delimit multiple words with a | .");    

        String b = scanner.nextLine();

        String[] words = b.split("|");
        for (String word: words )
        {
            String[] characters = word.split(" ");
            for (String character: characters) 
            {
                if (character.isEmpty()) { continue; }
        for (int m = 0; m < morse.length; m++)
                {
                    if (character.equals(morse[m]))    
                        System.out.print(english[m]);    
                }    
            }
            System.out.print(" ");    
        }    
    }
else if (a.equals("Eng"))
    {
        System.out.println("Please enter a sentence in English, and separate each word with a blank space.");
        String c = scanner.nextLine();

        c = c.toLowerCase ();

        for ( int x = 0; x < english.length; x++ )
        {
            for ( int y = 0; y < c.length (); y++ )
            {
                if ( english [ x ] == c.charAt ( y ) )

                System.out.print ( morse [ x ] + "  " );


            }

        }


    }

    else 
   {
       System.out.println ( "Invalid Input" );

    }

}
}

Please don't just do his work for him. Much better if you explain the changes. Better still would be to explain what he needs to do to make the changes, and then allow him to do create his own corrected code. — Hovercraft Full Of Eels, May 30 '15 at 20:40

Need assistance with java morse code translator only translating one symbol

2 Answers2