The Java Developers Almanac 1.4

e426. Removing Duplicate Whitespace in a String

    // Returns a version of the input where all contiguous
    // whitespace characters are replaced with a single
    // space. Line terminators are treated like whitespace.
    public static CharSequence removeDuplicateWhitespace(CharSequence inputStr) {
        String patternStr = "\\s+";
        String replaceStr = " ";
        Pattern pattern = Pattern.compile(patternStr);
        Matcher matcher = pattern.matcher(inputStr);
        return matcher.replaceAll(replaceStr);
    }

Related Examples

e423. Quintessential Regular Expression Search Program
e424. Determining If a String Matches a Pattern Exactly
e425. Applying Regular Expressions on the Contents of a File
e427. Greedy and Nongreedy Matching in a Regular Expression
e428. Escaping Special Characters in a Pattern

See also: Flags    Groups    Lines    Paragraphs    Searching and Replacing    Tokenizing

© 2002 Addison-Wesley.