# ConnectCallback.java

    /**
     *  Copyright (c) 2009, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
     *
     *  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 org.apache.synapse.transport.passthru;

    import org.apache.http.nio.reactor.SessionRequestCallback;
    import org.apache.http.nio.reactor.SessionRequest;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.apache.synapse.transport.passthru.connections.HostConnections;

    public class ConnectCallback implements SessionRequestCallback {

        private static Log log = LogFactory.getLog(ConnectCallback.class);

        /** The agent used for delivering requests */
        private DeliveryAgent deliveryAgent;

        /**
         * Create the callback for the handling events on a given connection
         */
        public ConnectCallback() {

        }

        public void completed(SessionRequest request) {
            HostConnections pool = (HostConnections) request.getAttachment();
            pool.pendingConnectionSucceeded();
            if (log.isDebugEnabled()) {
                if (request.getSession() != null &&
                        request.getSession().getLocalAddress() != null) {
                    log.debug("Connected to remote address: " +
                            request.getSession().getRemoteAddress() +
                            " from local address: " + request.getSession().getLocalAddress());
                }
            }
        }

        public void failed(SessionRequest request) {
            HostConnections pool = (HostConnections) request.getAttachment();
            pool.pendingConnectionFailed();

            deliveryAgent.errorConnecting(pool.getRoute(),
                    ErrorCodes.CONNECTION_FAILED, "Connection Failed");

            handleError("Connection refused or failed for : " + request.getRemoteAddress());
        }

        public void timeout(SessionRequest request) {
            HostConnections pool = (HostConnections) request.getAttachment();
            pool.pendingConnectionFailed();

            deliveryAgent.errorConnecting(pool.getRoute(),
                    ErrorCodes.CONNECT_TIMEOUT, "Connection Timeout");

            handleError("Timeout connecting to : " + request.getRemoteAddress());
            request.cancel();
        }

        public void cancelled(SessionRequest request) {
            HostConnections pool = (HostConnections) request.getAttachment();
            pool.pendingConnectionFailed();

            deliveryAgent.errorConnecting(pool.getRoute(),
                    ErrorCodes.CONNECT_CANCEL, "Connection Cancel");

            handleError("Connection cancelled for : " + request.getRemoteAddress());
        }

        private void handleError(String errorMessage) {
            log.warn(errorMessage);
        }

        public void setDeliveryAgent(DeliveryAgent deliveryAgent) {
            this.deliveryAgent = deliveryAgent;
        }
    }