public FileFilter (String description, String[] extensions)
public FileFilter (String extension)
    public FileFilter (String description,                       String[] extensions)    {        if (description == null) {            // Use first extension and # of extensions as desc.            this.description = extensions[0] + "{" + extensions.length + "}";        } else {            this.description = description;        }        // Convert array to lower case, once for all        this.extensions = extensions.clone();        for (int i = 0; i < this.extensions.length; i++) {            this.extensions[i] = this.extensions[i].toLowerCase();        }    }