Java String Manipulation : Comparing adjacent Characters in Java

Question

i have the following problem
Given a string, return a \"cleaned\" string where adjacent chars that are the same have been reduced to a single char. So \"yyzzza\"

Answer 1

I would do it like this:

public static String stringClean(String str) {
    if (str == null || "".equals(str))
        return str;
    StringBuffer buffer = new StringBuffer();
    char[] chars = str.toCharArray();
    buffer.append(chars[0]);
    for (int i = 1; i < chars.length; i++) {
        if (chars[i] != chars[i-1])
            buffer.append(chars[i]);
    }
    return buffer.toString();
}