java - 将多个字符翻译成一个

Question

我需要帮助将摩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码的代码。我的主要问题是将摩尔斯电码中的所有字符放在一起，然后再将其翻译成英文字符(如果有意义的话)。

例如:“。”转换为 E 并...转换为 S，但我不希望翻译在到达...之前开始

几条规则-空格用于分隔摩尔斯字母-|用作分隔单词的分隔符-不能使用 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字符串，直到我到达一个空白区域，然后使用它进行测试，但我不确定该怎么做。

感谢任何帮助，谢谢!

Answer 1

按从长到短的顺序创建一个包含所有摩尔斯电码序列的正则表达式。

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

然后将其与字符串重复匹配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'); }
  ...
  )
}