code: /*
   * 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.skywalking.oap.server.storage.plugin.jdbc;
  
  import java.sql.Statement;
  import lombok.RequiredArgsConstructor;
  import lombok.extern.slf4j.Slf4j;
  import org.apache.skywalking.oap.server.core.UnexpectedException;
  import org.apache.skywalking.oap.server.library.client.jdbc.hikaricp.JDBCClient;
  import org.apache.skywalking.oap.server.library.client.request.InsertRequest;
  import org.apache.skywalking.oap.server.library.client.request.PrepareRequest;
  import org.apache.skywalking.oap.server.library.client.request.UpdateRequest;
  
  import java.sql.PreparedStatement;
  import java.sql.SQLException;
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * A Batch SQL executor.
   */
  @Slf4j
  @RequiredArgsConstructor
  public class BatchSQLExecutor implements InsertRequest, UpdateRequest {
      private final JDBCClient jdbcClient;
      private final List<PrepareRequest> prepareRequests;
  
      public void invoke(int maxBatchSqlSize) throws Exception {
          if (log.isDebugEnabled()) {
              log.debug("execute sql batch. sql by key size: {}", prepareRequests.size());
          }
          if (prepareRequests.size() == 0) {
              return;
          }
          final var sql = prepareRequests.get(0).toString();
          final var bulkRequest = new ArrayList<PrepareRequest>(maxBatchSqlSize);
          try (final var connection = jdbcClient.getConnection();
               final var preparedStatement = connection.prepareStatement(sql)) {
              var pendingCount = 0;
              for (final var prepareRequest : prepareRequests) {
                  final var sqlExecutor = (SQLExecutor) prepareRequest;
                  if (log.isDebugEnabled()) {
                      log.debug("Executing sql: {}", sql);
                      log.debug("SQL parameters: {}", sqlExecutor.getParam());
                  }
                  sqlExecutor.setParameters(preparedStatement);
                  preparedStatement.addBatch();
                  bulkRequest.add(sqlExecutor);
                  if (bulkRequest.size() == maxBatchSqlSize) {
                      executeBatch(preparedStatement, maxBatchSqlSize, sql, bulkRequest);
                      bulkRequest.clear();
                      pendingCount = 0;
                  } else {
                      pendingCount++;
                  }
              }
              if (pendingCount > 0) {
                  executeBatch(preparedStatement, pendingCount, sql, bulkRequest);
                  bulkRequest.clear();
              }
          }
      }
  
      private void executeBatch(PreparedStatement preparedStatement,
                                int pendingCount,
                                String sql,
                                List<PrepareRequest> bulkRequest) throws SQLException {
          final var start = System.currentTimeMillis();
          final var executeBatchResults = preparedStatement.executeBatch();
          final var isInsert = bulkRequest.get(0) instanceof InsertRequest;
          for (int i = 0; i < executeBatchResults.length; i++) {
              if ((executeBatchResults[i] == 1 || executeBatchResults[i] == Statement.SUCCESS_NO_INFO) && isInsert) {
                  // Insert successfully.
                  ((InsertRequest) bulkRequest.get(i)).onInsertCompleted();
              } else if (executeBatchResults[i] == 0 && !isInsert) {
                  // Update Failure.
                  ((UpdateRequest) bulkRequest.get(i)).onUpdateFailure();
              }
          }
          if (log.isDebugEnabled()) {
              long end = System.currentTimeMillis();
              long cost = end - start;
              log.debug("execute batch sql, batch size: {}, cost:{}ms, sql: {}", pendingCount, cost, sql);
          }
      }
  
      @Override
      public void onInsertCompleted() {
          throw new UnexpectedException("BatchSQLExecutor.onInsertCompleted should not be called");
      }
  
      @Override
      public void onUpdateFailure() {
          throw new UnexpectedException("BatchSQLExecutor.onUpdateFailure should not be called");
      }
  }
  