Java Programming

something like

String text = text.replaceAll("[@#>]", "");

I am trying to extend the same logic for the following characters:

.,‘“?!@#%^&*()-~<>[]{}\+=`©® . here is the code fragment:

Pattern kValidator = Pattern.compile("[\\.,\\‘\\“?!@#%^&*()-~<>[]{}\\+=\\`©®]");
Matcher kMatcher = kValidator.matcher(keyWord);
		
if (kMatcher.find(0)) {
keyWord = keyWord.replaceAll("[.,\\‘\\“?!@#%^&*()-~<>[]{}\\+=\\`©®]", " ");
}

I get the following error. This error is from the weblogic command window. I dont understand these special characters.

Error: 

28 Oct 2008 12:27:48 | INFO  | SearchController   | Exception while fetching search results in controller:Unclosed character class near index
39
[\.,\&#915;Çÿ\&#915;Ç£?!@#%^&*()-~<>[]{}\+=\`&#9516;&#8976;&#9516;«]
                                       ^
java.util.regex.PatternSyntaxException: Unclosed character class near index 39
[\.,\&#915;Çÿ\&#915;Ç£?!@#%^&*()-~<>[]{}\+=\`&#9516;&#8976;&#9516;«]
                                       ^
        at java.util.regex.Pattern.error(Pattern.java:1650)
        at java.util.regex.Pattern.clazz(Pattern.java:2199)
        at java.util.regex.Pattern.sequence(Pattern.java:1727)
        at java.util.regex.Pattern.expr(Pattern.java:1687)
        at java.util.regex.Pattern.compile(Pattern.java:1397)
        at java.util.regex.Pattern.<init>(Pattern.java:1124)
        at java.util.regex.Pattern.compile(Pattern.java:817)

The cause of your problem is that you didn't save the file in the right charset encoding.

But there are much more 'special characters' than only those you have shown. Can't you just do it the reverse way and define a group of allowed characters and use regex to strip out the other characters using ^ ?

E.g.

string.replaceAll("[^\\w\\s]", "");

which allows aplhanumeric (word) characters (incl underscore) and spaces only.

To avoid the encoding problem, you can use Unicode escapes for any characters that are outside the seven-bit ASCII range. However, you also need to escape hyphens and square brackets within a character class--that's what the error message was about. Ironically, those characters that you did escape didn't need it, because they lose their special meanings in character classes.

keyWord = keyWord.replaceAll("[.,\u2018\u201C?!@#%^&*()\\-~<>\\[\\]{}+=`\u00A9\u00AE]", "");

But that's just FYI; if BalusC's suggestion will work for you, you should definitely do it that way. Whichever way you go, there's no need to call find() before doing the replacement; if there are no matches, replaceAll() will simply return the original string.

Hey, the solution worked. Thanks a bunch!!!