public String getCrossClassLink(String qualifiedClassName, String refMemName,
                                    String label, boolean bold, String style,
                                    boolean code) {
        String className = "",
            packageName = qualifiedClassName == null ? "" : qualifiedClassName;
        int periodIndex;
        while((periodIndex = packageName.lastIndexOf('.')) != -1) {
            className = packageName.substring(periodIndex + 1, packageName.length()) +
                (className.length() > 0 ? "." + className : "");
            String defaultLabel = code ? getCode() + className + getCodeEnd() : className;
            packageName = packageName.substring(0, periodIndex);
            if (getCrossPackageLink(packageName) != null) {
                //The package exists in external documentation, so link to the external
                //class (assuming that it exists).  This is definitely a limitation of
                //the -link option.  There are ways to determine if an external package
                //exists, but no way to determine if the external class exists.  We just
                //have to assume that it does.
                return getHyperLink(
                    configuration.extern.getExternalLink(packageName, relativePath,
                                className + ".html?is-external=true"),
                    refMemName == null ? "" : refMemName,
                    label == null || label.length() == 0 ? defaultLabel : label,
                    bold, style,
                    configuration.getText("doclet.Href_Class_Or_Interface_Title", packageName),
                    "");
            }
        }
        return null;
    }