Question

我需要帮助将莫尔斯电码转换为英语。我已经编写并测试了将英语翻译成莫尔斯语的代码。我的主要问题是如果有意义的话，将摩尔斯电码中的所有字符翻译成英文字符。

示例：“。”转换为E和...转换为S，但我不希望翻译在它到达之前开始......

几个规则 -Spaces用于分隔莫尔斯字母 - |用作分隔单词的分隔符 -Cant使用hashmap :(

这是我的代码

import java.util.Arrays;
import javax.swing.JOptionPane;

public class test3
{
public static void main ( String [] args )
{

    String s1 = "Morse";

    // Decide whether Morse code or English
    String decide = JOptionPane.showInputDialog("Enter 'English' for Morse to English code translation and 'Morse' for English to Morse code translation. Pay attention to Caps.");

    // Enter String & decide whether to convert to Morse or English
    String phrase = JOptionPane.showInputDialog("Enter the words you wish to translate.");

    if ( decide.equals( s1 ))
        toMorse( phrase );

    else
        toEnglish( phrase );
}

// Translate to Morse
public static void toMorse( String preTranslation )
{

    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"};

    String[] morse = {".-","-...","-.-.","-..",".","..-.","--.","....","..", ".---",
            "-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-", 
            "...-",".--","-..-","-.--","--..",".----","..---","...--","....-",".....","-....","--...","---..","----.","-----"};
    // Remove uppercase
    String preTrans = preTranslation.toLowerCase();

    // Deletes spaces
    String phraseWithDelimiter = preTrans.replace( " ", "|");

    String[] translation = new String[phraseWithDelimiter.length()];
    String[] delimiter = {"|"};

    // Translate 
    for ( int arrayVar = 0, transArrayVar = 0, subStringVarB = 0, subStringVarE = 1; transArrayVar < phraseWithDelimiter.length();)
    {
        if( phraseWithDelimiter.substring(subStringVarB, subStringVarE).equals( delimiter[0] ) )
        {
            translation[transArrayVar] = delimiter[0];
            transArrayVar++;
            subStringVarB++;
            subStringVarE++;
        }
        else if ( phraseWithDelimiter.substring(subStringVarB, subStringVarE).equals( english[arrayVar] ) )
            {
                translation[transArrayVar] = morse[arrayVar];
                transArrayVar++;
                subStringVarB++;
                subStringVarE++;
                arrayVar = 0;
            }
            else
            {
                arrayVar++;
                if ( arrayVar == 35 )
                {
                    arrayVar = 0;
                    subStringVarB++;
                    subStringVarE++;
                    transArrayVar++;
                }
            }
    }
String morseSeparator = new String( " " );
arrayToString ( translation, morseSeparator );

}


//Convert array to string and print translation
public static void arrayToString(String[] trans, String separator) 
{
    String result = "";
    if (trans.length > 0) 
    {
            result = trans[0];    // start with the first element
            for (int i = 1; i < trans.length; i++)
                result = result + separator + trans[i];
        }
    System.out.println( result );
}

    // unfinished
public static void toEnglish( String preTranslation)
{
    }

我正在考虑制作一个for语句，并将摩尔斯电码的每个字符分配给一个新的字符串，直到我到达一个空格，然后使用它进行测试，但我不确定如何做到这一点。

感谢任何帮助！

Answer 1

按照从最长到最短的顺序创建一个包含所有莫尔斯码序列的正则表达式。

 Pattern.compile("----\\.|-----|---\\.\\.|...")

然后只重复匹配字符串以获得最长的有效摩尔斯电码序列。

或者，您可以使用像JavaCC这样的解析器编译器。

SKIP : { " " }
TOKEN : { < A : "-." > }
TOKEN : { < B : "-..." > }
TOKEN : { < C : "-.-." > }
...

String translate() :
{ StringBuilder sb; }
{
  { sb = new StringBuilder(); }

  (
    letter(sb)
  )*
  <EOF>

  { return sb.toString(); }
}

void letter(StringBuilder sb) :
{}
{
  ( <A>
    { sb.append('a'); }
  | <B>
    { sb.append('b'); }
  | <C>
    { sb.append('c'); }
  ...
  )
}

Answer 2

对于翻译文本，您可以先尝试将其拆分为单词分隔符，然后再进行字符限制。然后逐个处理单词。与此类似：

String morseInput = //whatever, only delimiters or morse characters

String[] words = morseInput.split("-|");
for( String word : words ) {
  String[] characters = word.split("\\s");

  for( String c : characters ) {
    //look up the english character for c - I'd use a map here
  }
}

一些注意事项：

我省略了对空字符串的检查，为了简洁而忽略了
我也遗漏了构建最终翻译字符串的任何代码，这是一个适合你的练习
我使用Map<String, String>进行查找，如果不允许，查找源数组中字符的索引，然后从转换数组中获取该索引的转换

将多个字符翻译成一个

2 个答案: