/*
    * 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 org.apache.shardingsphere.proxy.frontend.postgresql.command.query.extended;
  
  import lombok.RequiredArgsConstructor;
  import org.apache.shardingsphere.db.protocol.packet.DatabasePacket;
  import org.apache.shardingsphere.db.protocol.postgresql.packet.command.query.extended.PostgreSQLAggregatedResponsesPacket;
  import org.apache.shardingsphere.proxy.frontend.command.executor.CommandExecutor;
  
  import java.sql.SQLException;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.LinkedList;
  import java.util.List;
  
  @RequiredArgsConstructor
  public final class PostgreSQLAggregatedCommandExecutor implements CommandExecutor {
      
      private final List<CommandExecutor> executors;
      
      @Override
      public Collection<DatabasePacket> execute() throws SQLException {
          List<DatabasePacket> result = new LinkedList<>();
          for (CommandExecutor each : executors) {
              try {
                  result.addAll(each.execute());
              } finally {
                  each.close();
              }
          }
          return Collections.singleton(new PostgreSQLAggregatedResponsesPacket(result));
      }
  }