content: /*
   * Copyright (c) 2002, 2020, Oracle and/or its affiliates.
   *
   * This program is free software; you can redistribute it and/or modify it under
   * the terms of the GNU General Public License, version 2.0, as published by the
   * Free Software Foundation.
   *
   * This program is also distributed with certain software (including but not
   * limited to OpenSSL) that is licensed under separate terms, as designated in a
   * particular file or component or in included license documentation. The
   * authors of MySQL hereby grant you an additional permission to link the
   * program and your derivative works with the separately licensed software that
   * they have included with MySQL.
   *
   * Without limiting anything contained in the foregoing, this file, which is
   * part of MySQL Connector/J, is also subject to the Universal FOSS Exception,
   * version 1.0, a copy of which can be found at
   * http://oss.oracle.com/licenses/universal-foss-exception.
   *
   * This program is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
   * FOR A PARTICULAR PURPOSE. See the GNU General Public License, version 2.0,
   * for more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
   */
  
  package com.mysql.cj.jdbc.integration.c3p0;
  
  import java.lang.reflect.Method;
  import java.sql.Connection;
  import java.sql.SQLException;
  import java.sql.Statement;
  
  import com.mchange.v2.c3p0.C3P0ProxyConnection;
  import com.mchange.v2.c3p0.QueryConnectionTester;
  import com.mysql.cj.exceptions.CJCommunicationsException;
  import com.mysql.cj.jdbc.JdbcConnection;
  import com.mysql.cj.jdbc.exceptions.CommunicationsException;
  
  /**
   * ConnectionTester for C3P0 connection pool that uses the more efficient COM_PING method of testing connection 'liveness' for MySQL, and 'sorts' exceptions
   * based on SQLState or class of 'CommunicationsException' for handling exceptions.
   */
  public final class MysqlConnectionTester implements QueryConnectionTester {
  
      private static final long serialVersionUID = 3256444690067896368L;
  
      private static final Object[] NO_ARGS_ARRAY = new Object[0];
  
      private transient Method pingMethod;
  
      public MysqlConnectionTester() {
          try {
              this.pingMethod = JdbcConnection.class.getMethod("ping", (Class[]) null);
          } catch (Exception ex) {
              // punt, we have no way to recover, other than we now use 'SELECT 1' for handling the connection testing.
          }
      }
  
      @Override
      public int activeCheckConnection(Connection con) {
          try {
              if (this.pingMethod != null) {
                  if (con instanceof JdbcConnection) {
                      // We've been passed an instance of a MySQL connection -- no need for reflection
                      ((JdbcConnection) con).ping();
                  } else {
                      // Assume the connection is a C3P0 proxy
                      C3P0ProxyConnection castCon = (C3P0ProxyConnection) con;
                      castCon.rawConnectionOperation(this.pingMethod, C3P0ProxyConnection.RAW_CONNECTION, NO_ARGS_ARRAY);
                  }
              } else {
                  Statement pingStatement = null;
  
                  try {
                      pingStatement = con.createStatement();
                      pingStatement.executeQuery("SELECT 1").close();
                  } finally {
                      if (pingStatement != null) {
                          pingStatement.close();
                      }
                  }
              }
  
              return CONNECTION_IS_OKAY;
          } catch (Exception ex) {
              return CONNECTION_IS_INVALID;
          }
      }
  
      @Override
      public int statusOnException(Connection arg0, Throwable throwable) {
          if (throwable instanceof CommunicationsException || throwable instanceof CJCommunicationsException) {
              return CONNECTION_IS_INVALID;
          }
  
          if (throwable instanceof SQLException) {
              String sqlState = ((SQLException) throwable).getSQLState();
  
              if (sqlState != null && sqlState.startsWith("08")) {
                  return CONNECTION_IS_INVALID;
              }
  
              return CONNECTION_IS_OKAY;
          }
  
          // Runtime/Unchecked?
  
          return CONNECTION_IS_INVALID;
      }
  
      @Override
      public int activeCheckConnection(Connection arg0, String arg1) {
          return CONNECTION_IS_OKAY;
      }
  }
  