Android String to Title Case

title_case.java

public static String toTitleCase(String str) {

    if (str == null) {
        return null;
    }

    boolean space = true;
    StringBuilder builder = new StringBuilder(str);
    final int len = builder.length();

    for (int i = 0; i < len; ++i) {
        char c = builder.charAt(i);
        if (space) {
            if (!Character.isWhitespace(c)) {
                // Convert to title case and switch out of whitespace mode.
                builder.setCharAt(i, Character.toTitleCase(c));
                space = false;
            }
        } else if (Character.isWhitespace(c)) {
            space = true;
        } else {
            builder.setCharAt(i, Character.toLowerCase(c));
        }
    }

    return builder.toString();
}