content: /*
   *
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   *
   */
  
  package com.alibaba.cloudapp.datasource.druid;
  
  import com.alibaba.druid.filter.FilterAdapter;
  import com.alibaba.druid.filter.FilterChain;
  import com.alibaba.druid.pool.DruidDataSource;
  import com.alibaba.druid.pool.DruidPooledConnection;
  
  import java.sql.SQLException;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.Map;
  import java.util.concurrent.ConcurrentHashMap;
  
  public class ConnectionRememberSetFilter extends FilterAdapter {
  
      private static final Boolean PRESENT = Boolean.TRUE;
  
      private Map<DruidPooledConnection, Boolean> activeConnections = new ConcurrentHashMap<>();
  
      @Override
      public void dataSource_releaseConnection(FilterChain chain, DruidPooledConnection connection) throws SQLException {
          try {
              chain.dataSource_recycle(connection);
          } finally {
              activeConnections.remove(connection);
          }
  
      }
  
      public Collection<DruidPooledConnection> getActiveConnections() {
          return Collections.unmodifiableSet(activeConnections.keySet());
      }
  
      @Override
      public DruidPooledConnection dataSource_getConnection(FilterChain chain, DruidDataSource dataSource,
                                                            long maxWaitMillis) throws SQLException {
          DruidPooledConnection connection = chain.dataSource_connect(dataSource, maxWaitMillis);
  
          activeConnections.put(connection, PRESENT);
          return connection;
      }
  }
  