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1   /*
2    * This file is part of Waarp Project (named also Waarp or GG).
3    *
4    *  Copyright (c) 2019, Waarp SAS, and individual contributors by the @author
5    *  tags. See the COPYRIGHT.txt in the distribution for a full listing of
6    * individual contributors.
7    *
8    *  All Waarp Project is free software: you can redistribute it and/or
9    * modify it under the terms of the GNU General Public License as published by
10   * the Free Software Foundation, either version 3 of the License, or (at your
11   * option) any later version.
12   *
13   * Waarp is distributed in the hope that it will be useful, but WITHOUT ANY
14   * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
15   * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
16   *
17   *  You should have received a copy of the GNU General Public License along with
18   * Waarp . If not, see <http://www.gnu.org/licenses/>.
19   */
20  
21  package org.waarp.common.database.properties;
22  
23  import java.sql.Connection;
24  import java.sql.ResultSet;
25  import java.sql.SQLException;
26  import java.sql.Statement;
27  
28  /**
29   * MariaDB Database Model
30   */
31  public class MariaDBProperties implements DbProperties {
32    private static final String PROTOCOL = "mariadb";
33  
34    private static final String DRIVER_NAME = "org.mariadb.jdbc.Driver";
35    private static final String VALIDATION_QUERY = "select 1";
36    private static final String MAX_CONNECTION_QUERY =
37        "select GLOBAL_VALUE " + "from INFORMATION_SCHEMA.SYSTEM_VARIABLES " +
38        "where VARIABLE_NAME LIKE 'max_connections'";
39  
40    public MariaDBProperties() {
41      // nothing
42    }
43  
44    public static String getProtocolID() {
45      return PROTOCOL;
46    }
47  
48    @Override
49    public final String getDriverName() {
50      return DRIVER_NAME;
51    }
52  
53    @Override
54    public final String getValidationQuery() {
55      return VALIDATION_QUERY;
56    }
57  
58    @Override
59    public final int getMaximumConnections(final Connection connection)
60        throws SQLException {
61      Statement stm = null;
62      ResultSet rs = null;
63      try {
64        stm = connection.createStatement();
65        rs = stm.executeQuery(MAX_CONNECTION_QUERY);
66        if (!rs.next()) {
67          throw new SQLException("Cannot find max connection");
68        }
69        return rs.getInt(1);
70      } finally {
71        if (rs != null) {
72          try {
73            rs.close();
74          } catch (final SQLException ignored) {
75            // nothing
76          }
77        }
78        if (stm != null) {
79          try {
80            stm.close();
81          } catch (final SQLException ignored) {
82            // nothing
83          }
84        }
85      }
86    }
87  }