Java replace Japanese characters with \\p{Katakana} regular expression

Question

i have followed that link

and the user "slevithan" offer using \p{Katakana}

public static void main(String[] args) {
    String str = "マイポケット (1).csv";
    str=    str.replaceAll(  "[\\p{Katakana}]", "_");//.replaceAll("\\p{Z}", "_");
    System.out.println(str);
}

but i get an error:

Exception in thread "main" java.util.regex.PatternSyntaxException: Unknown character property name {Katakana} near index 12
[\p{Katakana}]

i am working with java 8 . what is the correct syntax for checking Japanese characters with String replaceAll ?

that letter ポ is not recognized as katakana which it is. can you help me ? — 2Big2BeSmall, Jul 10 '16 at 14:48

score 0 · Accepted Answer · answered Aug 24 '16 at 10:41

0

The best solution was with this Regular-Expression when working with negative look-ahead .

str.replaceAll("(?![-,.,/p{Han}/p{Hiragana}/p{Katakana},\\p{IsAlphabetic}\\p{IsDigit}])[\\p{Punct}\\s]", "_");

answered Aug 24 '16 at 10:41

2Big2BeSmall

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score -1 · Answer 2 · answered Jul 10 '16 at 14:55

-1

i needed to support both English and Japanese letters

that regular expression did the trick:

str.replaceAll(  "[/p{Han}/p{Hiragana}/p{Katakana}&&[^\\.^\\p{IsAlphabetic}^\\p{IsDigit}^-]]", "_");

answered Jul 10 '16 at 14:55

2Big2BeSmall

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`[\\p{InKatakana}\\w]` will also work if you want English character – rock321987 Jul 10 '16 at 14:57
2

and why are you using `^` three times? – rock321987 Jul 10 '16 at 14:58
1

the use of /p its working in java 8 - which is exactly like writing \\p – 2Big2BeSmall Jul 10 '16 at 15:52
1

@rock321987 what if i want to support all possible languages ? – 2Big2BeSmall Jul 10 '16 at 15:53
@rock321987 notice that /p{Katakana} and \\p{InKatakana} are not the same \\p{InKatakana} does not support the letter ポ which /p{Katakana} does support it – 2Big2BeSmall Jul 10 '16 at 15:58
for supporting all possible language, simply use `\\p{L}` – rock321987 Jul 11 '16 at 01:40
The forward slash does not have a special meaning in Java regular expressions. For example, the two regular expressions `[/p{Katakana}]` and `[{}/Kaknpt]` are equivalent. – Roland Illig Jul 11 '16 at 19:38

Java replace Japanese characters with \\p{Katakana} regular expression

2 Answers2