如何替换java String中的字符？

Question

我喜欢以有效的方式用相应的替换字符替换字符串的某组字符.

例如:

String sourceCharacters = "š???Š???žŽ";
String targetCharacters = "sdccSDCCzZ";

String result = replaceChars("Gra?iš?e", sourceCharacters , targetCharacters );

Assert.equals(result,"Gracisce") == true;

有没有比使用replaceAllString类的方法更有效的方法？

我的第一个想法是:

final String s = "Gra?iš?e";
String sourceCharacters = "š???Š???žŽ";
String targetCharacters = "sdccSDCCzZ";

// preparation
final char[] sourceString = s.toCharArray();
final char result[] = new char[sourceString.length];
final char[] targetCharactersArray = targetCharacters.toCharArray();

// main work
for(int i=0,l=sourceString.length;i<l;++i)
{
  final int pos = sourceCharacters.indexOf(sourceString[i]);
  result[i] = pos!=-1 ? targetCharactersArray[pos] : sourceString[i];
}

// result
String resultString = new String(result);

有任何想法吗？

顺便说一句,UTF-8字符引起麻烦,US_ASCII可以正常工作.

Answer 1

你可以利用java.text.Normalizer和正则表达式来摆脱存在的变音符号,远远超过你收集的那些.

这是一个SSCCE,在Java 6上复制' n'paste'n'run它:

package com.stackoverflow.q2653739;

import java.text.Normalizer;
import java.text.Normalizer.Form;

public class Test {

    public static void main(String... args) {
        System.out.println(removeDiacriticalMarks("Gra?iš?e"));
    }

    public static String removeDiacriticalMarks(String string) {
        return Normalizer.normalize(string, Form.NFD)
            .replaceAll("\\p{InCombiningDiacriticalMarks}+", "");
    }
}

这应该产生

Gracisce

至少,它在Eclipse中将控制台字符编码设置为UTF-8(Window> Preferences> General> Workspace> Text File Encoding).确保在您的环境中也设置了相同的设置.

作为替代方案,维护一个Map<Character, Character>:

Map<Character, Character> charReplacementMap = new HashMap<Character, Character>();
charReplacementMap.put('š', 's');
charReplacementMap.put('?', 'd');
// Put more here.

String originalString = "Gra?iš?e";
StringBuilder builder = new StringBuilder();

for (char currentChar : originalString.toCharArray()) {
    Character replacementChar = charReplacementMap.get(currentChar);
    builder.append(replacementChar != null ? replacementChar : currentChar);
}

String newString = builder.toString();