/*
    *    Copyright 2016-2025 the original author or authors.
    *
    *    Licensed 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
    *
    *       https://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.mybatis.dynamic.sql.select;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.List;
  import java.util.Objects;
  import java.util.stream.Stream;
  
  import org.mybatis.dynamic.sql.BasicColumn;
  import org.mybatis.dynamic.sql.util.Validator;
  
  public class GroupByModel {
      private final List<BasicColumn> columns = new ArrayList<>();
  
      private GroupByModel(Collection<? extends BasicColumn> columns) {
          Objects.requireNonNull(columns);
          Validator.assertNotEmpty(columns, "ERROR.11"); //$NON-NLS-1$
          this.columns.addAll(columns);
      }
  
      public Stream<BasicColumn> columns() {
          return columns.stream();
      }
  
      public static GroupByModel of(Collection<? extends BasicColumn> columns) {
          return new GroupByModel(columns);
      }
  }