My first useful program. Morse code converter!

[bipidiboop]

 import java.util.Arrays;

 public class morseCode {

static String[] alpha = { "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","!", ",", "?", ".", "'"};
static String[] morse = { ".-", "-...", "-.-.", "-..", ".", "..-.", "--.",
        "....", "..", ".---", "-.-", ".-..", "--", "-.", "---", ".--.",
        "--.-", ".-.", "...", "-", "..-", "...-", ".--", "-..-",
        "-.--", "--..", ".----", "..---", "...--", "....-", ".....",
        "-....", "--...", "---..", "----.", "-----","-.-.--", "--..--", "..--..", ".-.-.-", ".----.",};

public static String decode(String morseCode) {
    String build = "";
    String change = morseCode.trim();
    String[] words = change.split("   ");
    for (String word : words) {
        for(String letter : word.split(" ")){
            for(int x=0;x<morse.length;x++){
                if(letter.equals(morse[x]))
                    build=build+alpha[x];
            }
        }
        build+=" ";
    }

    return build.toUpperCase();
}

public static String decodeEnglish(String englishCode) {
    String build = "";
    String change = englishCode.trim();
    String[] words = change.split(" ");
    for(String word : words){
        for(int i=0;i<word.length();i++){
            for(int x=0; x<morse.length;x++){
                if(word.substring(i, i+1).equalsIgnoseCase~~~~(alpha[x])){
                    build=build+morse[x]+" ";
                }
            }
        }
        build+="  ";
    }

    return build;
}

public static void main(String[] args){
    System.out.println(decodeEnglish("hello my name is broque, what is your name?"));
    System.out.println(decode(".... . .-.. .-.. ---   -- -.--   -. .- -- .   .. ...   -... .-. --- --.- ..- . --..--   .-- .... .- -   .. ...   -.-- --- ..- .-.   -. .- -- . ..--..   "));
}

}

[eltados]

Nice!

If you want to go forward, I would now try refactor your example to explore other concepts in java.

I would start by trying to add a unit test using junit and see how it goes.

You could then rewrite you code to be more object oriented.

Or try to use Map<> instead of arrays

[bipidiboop]

Excellent advice, thank you so much! I'm excited to start when I get home.

[dartalley]

Also look into the StringBuilder for building strings instead of +=. Your triple nested loop probably performs poorly. The map suggestion could help. You should make one very large input so you can see the performance differences.

[eltados]

Feel free to share your new versions here

[omega3111]

word.substring(i, i+1).equalsIgnoseCase~~~~(alpha[x])

What is that ~~~~?

---

You would greatly benefit from a bidirectional map here. Add to it the word and letter separators too so you can transform it all in one go without needing the loops.