需要补偿莫尔斯电码解码器中的空白

Question

所以我制作了一个运行良好的摩尔斯电码解码器。唯一的问题是它不能补偿条目开头和结尾的空白。所以说我有“。”这是摩尔斯电码中的E。我应该能够输入“__._”并得到相同的结果，但我只是得到了一个例外。当它进入时，我尝试在条目上使用修剪方法，这消除了异常，但我没有得到任何输出。我尝试使用循环来摆脱前面的空白，但我没有得到任何输出，即使这样有效，我仍然需要弄清楚如何处理后面的空白。这是我的代码：

 static String[] 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",
            ",", ".", "?","!","@","&","(",")"};   //Defining a Character Array of the English Letters numbers and Symbols so that we can compare and convert later 

   static  String[] morse = { " " ,".-", "-...", "-.-.", "-..", ".", "..-.", "--.", "....", "..", 
               ".---", "-.-", ".-..", "--", "-.", "---", ".--.", "--.-", ".-.",
               "...", "-", "..-", "...-", ".--", "-..-", "-.--", "--..", ".----",
               "..---", "...--", "....-", ".....", "-....", "--...", "---..", "----.",
               "-----", "--..--", ".-.-.-", "..--..","-.-.--",".--.-.",".-...","-.--.","-.--.-"}; 
public static String Decode (String morseCode)
{
    
    String MLetter= "";//Morsec array to hold individual characters
    String ELetter ="";//English Letter String
    morseCode+="  ";
    for(int i=0; i<morseCode.length();i++)//put characters into the morse String
    {
        if(morseCode.substring(i,i+1).equals(" "))//if a space is detected
        {   
            for(int j=0; j<morse.length;j++)// then compare the string to the morse array
                {
                    if(MLetter.equals(morse[j]))//if the morse string equals the morse index
                        {
                            ELetter+=english[j];//add the english equivilent
                            MLetter="";//and clear the Morse string
                            i++;//Skip the space
                        }
                }
        }
        MLetter+= morseCode.substring(i,i+1);//add the character to the Morse String
        
    }

return ELetter.toUpperCase();
}

Answer 1

丑陋但有效：

        String MLetter= "";//Morsec array to hold individual characters
        String ELetter ="";//English Letter String
        String morseCodeTrimmed = "";
        // trim front white spaces
        while (morseCode.startsWith(" ")) {
            morseCode = morseCode.substring(1, morseCode.length());
        }
        // trim ending white spaces
        while (morseCode.endsWith(" ")) {
            morseCode = morseCode.substring(0, morseCode.length() - 1);
        }
        // for some reason that I'm not quite sure, 2 white spaces need 
        // to be added back to the end of the string.  
        // A good solution will not have this.
        morseCodeTrimmed = morseCode + "  ";

        ...