content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * Licensed 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.druid.util;
  
  import org.h2.jdbc.JdbcConnection;
  import org.h2.jdbcx.JdbcDataSourceFactory;
  import org.h2.jdbcx.JdbcXAConnection;
  import org.h2.message.TraceObject;
  
  import javax.sql.XAConnection;
  
  import java.lang.reflect.Constructor;
  import java.lang.reflect.Method;
  import java.sql.Connection;
  import java.sql.SQLException;
  
  public class H2Utils {
      private static volatile Constructor<JdbcXAConnection> constructor;
  
      private static volatile Method method;
  
      public static final int XA_DATA_SOURCE = 13;
  
      public static Object createJdbcDataSourceFactory() {
          return new JdbcDataSourceFactory();
      }
  
      public static XAConnection createXAConnection(Object factory, Connection physicalConn) throws SQLException {
          try {
              if (constructor == null) {
                  constructor = JdbcXAConnection.class.getDeclaredConstructor(JdbcDataSourceFactory.class, int.class,
                          JdbcConnection.class);
                  constructor.setAccessible(true);
              }
  
              int id = getNextId(XA_DATA_SOURCE);
  
              return constructor.newInstance(factory, id, physicalConn);
          } catch (Exception e) {
              throw new SQLException("createXAConnection error", e);
          }
      }
  
      public static int getNextId(int type) throws Exception {
          if (method == null) {
              method = TraceObject.class.getDeclaredMethod("getNextId", int.class);
              method.setAccessible(true);
          }
  
          return (Integer) method.invoke(null, type);
      }
  }
  