content: /*
   * Copyright (c) 2021, 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.protocol;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import com.mysql.cj.exceptions.CJOperationNotSupportedException;
  import com.mysql.cj.exceptions.ExceptionFactory;
  
  public interface ServerSessionStateController {
      public static int SESSION_TRACK_SYSTEM_VARIABLES = 0x00;
      public static int SESSION_TRACK_SCHEMA = 0x01;
      public static int SESSION_TRACK_STATE_CHANGE = 0x02;
      public static int SESSION_TRACK_GTIDS = 0x03;
      public static int SESSION_TRACK_TRANSACTION_CHARACTERISTICS = 0x04;
      public static int SESSION_TRACK_TRANSACTION_STATE = 0x05;
  
      /**
       * Set the object containing server session changes collected from the latest query execution. Used internally.
       * 
       * @param changes
       *            {@link ServerSessionStateChanges} object.
       * 
       */
      default void setSessionStateChanges(ServerSessionStateChanges changes) {
          throw ExceptionFactory.createException(CJOperationNotSupportedException.class, "Not supported");
      }
  
      /**
       * Get the object containing server session changes collected from the latest query execution.
       * <p>
       * Please note that the driver could issue some queries internally. With that there is no guarantee that all session changes are reflected in the
       * {@link ServerSessionStateChanges} object after the recent user's query. If this is an issue, a {@link SessionStateChangesListener} can be added via
       * {@link #addSessionStateChangesListener(SessionStateChangesListener)} to catch all session changes.
       * </p>
       * 
       * @return {@link ServerSessionStateChanges} object.
       */
      default ServerSessionStateChanges getSessionStateChanges() {
          throw ExceptionFactory.createException(CJOperationNotSupportedException.class, "Not supported");
      }
  
      @FunctionalInterface
      public static interface SessionStateChangesListener {
          void handleSessionStateChanges(ServerSessionStateChanges changes);
      }
  
      /**
       * Add the {@link SessionStateChangesListener} that will process {@link ServerSessionStateChanges} on it's arrival.
       * 
       * @param l
       *            {@link SessionStateChangesListener} object.
       */
      default void addSessionStateChangesListener(SessionStateChangesListener l) {
          throw ExceptionFactory.createException(CJOperationNotSupportedException.class, "Not supported");
      }
  
      /**
       * Remove {@link SessionStateChangesListener}.
       * 
       * @param l
       *            {@link SessionStateChangesListener} object.
       */
      default void removeSessionStateChangesListener(SessionStateChangesListener l) {
          throw ExceptionFactory.createException(CJOperationNotSupportedException.class, "Not supported");
      }
  
      /**
       * The object containing server session changes collected from the latest query execution.
       * <p>
       * Driver is getting these changes when connection property trackSessionState=true and server supports session tracking.
       * </p>
       * 
       */
      public static interface ServerSessionStateChanges {
          List<SessionStateChange> getSessionStateChangesList();
      }
  
      /**
       * A single server session change record.
       * <p>
       * The server messages about session changes are parsed according to their known types:
       * <ul>
       * <li>{@link #SESSION_TRACK_SYSTEM_VARIABLES} - two values, the system variable name and it's new value;</li>
       * <li>{@link #SESSION_TRACK_SCHEMA} - single value, the new schema name;</li>
       * <li>{@link #SESSION_TRACK_STATE_CHANGE} - single value, "1" or "0";</li>
       * <li>{@link #SESSION_TRACK_GTIDS} - single value, list of GTIDs as reported by server;</li>
       * <li>{@link #SESSION_TRACK_TRANSACTION_CHARACTERISTICS} - single value, transaction characteristics statement;</li>
       * <li>{@link #SESSION_TRACK_TRANSACTION_STATE} - single value, transaction state record.</li>
       * </ul>
       * For the unknown change type the raw payload is written into the single value.
       * </p>
       * <p>
       * See more details in the <a href="https://dev.mysql.com/doc/refman/8.0/en/session-state-tracking.html">server documentation</a>.
       * </p>
       */
      public static class SessionStateChange {
          private int type;
          private List<String> values = new ArrayList<>();
  
          public SessionStateChange(int type) {
              this.type = type;
          }
  
          public int getType() {
              return this.type;
          }
  
          public List<String> getValues() {
              return this.values;
          }
  
          public SessionStateChange addValue(String value) {
              this.values.add(value);
              return this;
          }
      }
  }
  