How to replace characters in a java String?
I like to replace a certain set of characters of a string with a corresponding replacement character in an efficent way.
For example:
String sourceCharacters = "šđćčŠĐĆČžŽ";
String targetCharacters = "sdccSDCCzZ";
String result = replaceChars("Gračišće", sourceCharacters , targetCharacters );
Assert.equals(result,"Gracisce") == true;
Is there are more efficient way than to use the replaceAll
method of the String class?
My first idea was:
final String s = "Gračišće";
String sourceCharacters = "šđćčŠĐĆČžŽ";
String targetCharacters = "sdccSDCCzZ";
// preparation
final char[开发者_如何学C] 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);
Any ideas?
Btw, the UTF-8 characters are causing the trouble, with US_ASCII it works fine.
You can make use of java.text.Normalizer
and a shot of regex to get rid of the diacritics of which there exist much more than you have collected as far.
Here's an SSCCE, copy'n'paste'n'run it on Java 6:
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("Gračišće"));
}
public static String removeDiacriticalMarks(String string) {
return Normalizer.normalize(string, Form.NFD)
.replaceAll("\\p{InCombiningDiacriticalMarks}+", "");
}
}
This should yield
Gracisce
At least, it does here at Eclipse with console character encoding set to UTF-8 (Window > Preferences > General > Workspace > Text File Encoding). Ensure that the same is set in your environment as well.
As an alternative, maintain a Map<Character, Character>
:
Map<Character, Character> charReplacementMap = new HashMap<Character, Character>();
charReplacementMap.put('š', 's');
charReplacementMap.put('đ', 'd');
// Put more here.
String originalString = "Gračišće";
StringBuilder builder = new StringBuilder();
for (char currentChar : originalString.toCharArray()) {
Character replacementChar = charReplacementMap.get(currentChar);
builder.append(replacementChar != null ? replacementChar : currentChar);
}
String newString = builder.toString();
I'd use the replace
method in a simple loop.
String sourceCharacters = "šđćčŠĐĆČžŽ";
String targetCharacters = "sdccSDCCzZ";
String s = "Gračišće";
for (int i=0 ; i<sourceCharacters.length() ; i++)
s = s.replace(sourceCharacters.charAt[i], targetCharacters.charAt[i]);
System.out.println(s);
精彩评论