Copyright (c) 2002, 2017, Oracle and/or its affiliates. All rights reserved.

  The MySQL Connector/J is licensed under the terms of the GPLv2
  <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most MySQL Connectors.
  There are special exceptions to the terms and conditions of the GPLv2 as it is applied to
  this software, see the FOSS License Exception

  This program is free software; you can redistribute it and/or modify it under the terms
  of the GNU General Public License as published by the Free Software Foundation; version 2
  of the License.

  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 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.jdbc.jdbc2.optional;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.sql.SQLException;
import java.util.Map;

import com.mysql.jdbc.ExceptionInterceptor;
import com.mysql.jdbc.SQLError;
import com.mysql.jdbc.Util;

 * Base class for all wrapped instances created by LogicalHandle
abstract class WrapperBase {
    protected MysqlPooledConnection pooledConnection;

     * Fires connection error event if required, before re-throwing exception
     * @param sqlEx
     *            the SQLException that has occurred
     * @throws SQLException
     *             (rethrown)
    protected void checkAndFireConnectionError(SQLException sqlEx) throws SQLException {
        if (this.pooledConnection != null) {
            if (SQLError.SQL_STATE_COMMUNICATION_LINK_FAILURE.equals(sqlEx.getSQLState())) {
                this.pooledConnection.callConnectionEventListeners(MysqlPooledConnection.CONNECTION_ERROR_EVENT, sqlEx);

        throw sqlEx;

    protected Map<Class<?>, Object> unwrappedInterfaces = null;
    protected ExceptionInterceptor exceptionInterceptor;

    protected WrapperBase(MysqlPooledConnection pooledConnection) {
        this.pooledConnection = pooledConnection;
        this.exceptionInterceptor = this.pooledConnection.getExceptionInterceptor();

    protected class ConnectionErrorFiringInvocationHandler implements InvocationHandler {
        Object invokeOn = null;

        public ConnectionErrorFiringInvocationHandler(Object toInvokeOn) {
            this.invokeOn = toInvokeOn;

        public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
            if ("equals".equals(method.getName())) {
                // Let args[0] "unwrap" to its InvocationHandler if it is a proxy.
                return args[0].equals(this);

            Object result = null;

            try {
                result = method.invoke(this.invokeOn, args);

                if (result != null) {
                    result = proxyIfInterfaceIsJdbc(result, result.getClass());
            } catch (InvocationTargetException e) {
                if (e.getTargetException() instanceof SQLException) {
                    checkAndFireConnectionError((SQLException) e.getTargetException());
                } else {
                    throw e;

            return result;

         * Recursively checks for interfaces on the given object to determine
         * if it implements a java.sql interface, and if so, proxies the
         * instance so that we can catch and fire SQL errors.
         * @param toProxy
         * @param clazz
        private Object proxyIfInterfaceIsJdbc(Object toProxy, Class<?> clazz) {
            Class<?>[] interfaces = clazz.getInterfaces();

            for (Class<?> iclass : interfaces) {
                String packageName = Util.getPackageName(iclass);

                if ("java.sql".equals(packageName) || "javax.sql".equals(packageName)) {
                    return Proxy.newProxyInstance(toProxy.getClass().getClassLoader(), interfaces, new ConnectionErrorFiringInvocationHandler(toProxy));

                return proxyIfInterfaceIsJdbc(toProxy, iclass);

            return toProxy;