import org.kohsuke.args4j.CmdLineException;
import org.kohsuke.args4j.spi.Parameters;

class HandleException {
  void pattern(Parameters params) {
    String param = null;
    try {
      param = params.getParameter(0);
    } catch (CmdLineException e) {}
    
    if (param == null) {
      // do something
    } else {
      param.toLowerCase();
    }
  }
}
