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1   /*
2    *    Copyright 2016-2025 the original author or authors.
3    *
4    *    Licensed under the Apache License, Version 2.0 (the "License");
5    *    you may not use this file except in compliance with the License.
6    *    You may obtain a copy of the License at
7    *
8    *       https://www.apache.org/licenses/LICENSE-2.0
9    *
10   *    Unless required by applicable law or agreed to in writing, software
11   *    distributed under the License is distributed on an "AS IS" BASIS,
12   *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   *    See the License for the specific language governing permissions and
14   *    limitations under the License.
15   */
16  package org.mybatis.dynamic.sql.util.mybatis3;
17  
18  import org.apache.ibatis.annotations.SelectProvider;
19  import org.mybatis.dynamic.sql.select.render.SelectStatementProvider;
20  import org.mybatis.dynamic.sql.util.SqlProviderAdapter;
21  
22  /**
23   * This is a general purpose MyBatis mapper for count statements. Count statements are select statements that always
24   * return a long.
25   *
26   * <p>This mapper can be injected as-is into a MyBatis configuration, or it can be extended with existing mappers.
27   *
28   * @author Jeff Butler
29   */
30  public interface CommonCountMapper {
31      /**
32       * Execute a select statement that returns a long (typically a select(count(*)) statement). This mapper
33       * assumes the statement returns a single row with a single column that cen be retrieved as a long.
34       *
35       * @param selectStatement the select statement
36       * @return the long value
37       */
38      @SelectProvider(type = SqlProviderAdapter.class, method = "select")
39      long count(SelectStatementProvider selectStatement);
40  }