content: /*
   * Copyright (c) 2017, 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.ha;
  
  import java.lang.reflect.InvocationHandler;
  import java.sql.SQLException;
  import java.util.List;
  import java.util.Map;
  
  import com.mysql.cj.jdbc.ConnectionImpl;
  import com.mysql.cj.jdbc.JdbcConnection;
  import com.mysql.cj.util.StringUtils;
  
  public class ServerAffinityStrategy extends RandomBalanceStrategy {
      public String[] affinityOrderedServers = null;
  
      public ServerAffinityStrategy(String affinityOrdervers) {
          super();
          if (!StringUtils.isNullOrEmpty(affinityOrdervers)) {
              this.affinityOrderedServers = affinityOrdervers.split(",");
          }
      }
  
      @Override
      public ConnectionImpl pickConnection(InvocationHandler proxy, List<String> configuredHosts, Map<String, JdbcConnection> liveConnections,
              long[] responseTimes, int numRetries) throws SQLException {
          if (this.affinityOrderedServers == null) {
              return super.pickConnection(proxy, configuredHosts, liveConnections, responseTimes, numRetries);
          }
          Map<String, Long> blockList = ((LoadBalancedConnectionProxy) proxy).getGlobalBlocklist();
  
          for (String host : this.affinityOrderedServers) {
              if (configuredHosts.contains(host) && !blockList.containsKey(host)) {
                  ConnectionImpl conn = (ConnectionImpl) liveConnections.get(host);
                  if (conn != null) {
                      return conn;
                  }
                  try {
                      conn = ((LoadBalancedConnectionProxy) proxy).createConnectionForHost(host);
                      return conn;
                  } catch (SQLException sqlEx) {
                      if (((LoadBalancedConnectionProxy) proxy).shouldExceptionTriggerConnectionSwitch(sqlEx)) {
                          ((LoadBalancedConnectionProxy) proxy).addToGlobalBlocklist(host);
                      }
                  }
              }
          }
  
          // Failed to connect to all hosts in the affinity list. Delegate to RandomBalanceStrategy.
          return super.pickConnection(proxy, configuredHosts, liveConnections, responseTimes, numRetries);
      }
  }
  