/**

  * Licensed to the Apache Software Foundation (ASF) under one or more

  * contributor license agreements.  See the NOTICE file distributed with

  * this work for additional information regarding copyright ownership.

  * The ASF licenses this file to You under the Apache License, Version 2.0

  * (the "License"); you may not use this file except in compliance with

  * the License.  You may obtain a copy of the License at

  *

  *     http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 package org.apache.commons.cli2;

 import java.util.Comparator;

 import java.util.Set;

 /**

  * An Option representing a choice or group of Options in the form "-a|-b|-c".

  */

 public interface Group extends Option {

     /**

      * Appends usage information to the specified StringBuffer

      *

      * @param buffer the buffer to append to

      * @param helpSettings a set of display settings @see DisplaySetting

      * @param comp a comparator used to sort the Options

      * @param separator the String used to separate member Options

      */

     void appendUsage(

         final StringBuffer buffer,

         final Set helpSettings,

         final Comparator comp,

         final String separator);

     /**

      * Indicates whether group members must be present for the CommandLine to be

      * valid.

      *

      * @see #getMinimum()

      * @see #getMaximum()

      * @return true iff the CommandLine will be invalid without at least one

      *         member option

      */

     boolean isRequired();

     /**

      * Retrieves the minimum number of members required for a valid Group

      *

      * @return the minimum number of members

      */

     int getMinimum();

     /**

      * Retrieves the maximum number of members acceptable for a valid Group

      *

      * @return the maximum number of members

      */

     int getMaximum();

 }