# MessageFormatterDecoratorFactory.java

    /*
    *  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.synapse.transport.nhttp.util;

    import org.apache.axis2.AxisFault;
    import org.apache.axis2.context.MessageContext;
    import org.apache.axis2.transport.MessageFormatter;
    import org.apache.axis2.transport.TransportUtils;
    import org.apache.axis2.util.MessageProcessorSelector;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.apache.http.protocol.HTTP;

    import java.util.Map;

    /**
     * Factory for getting Decorator to Message Formatter . This decorator is needed when extending
     * message formatter  by adding decoration functionality
     */
    public class MessageFormatterDecoratorFactory {

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

        private static final String GZIP_CODEC = "gzip";

        public static MessageFormatter createMessageFormatterDecorator(MessageContext msgContext) {

            if (msgContext == null) {
                throw new IllegalArgumentException("Message Context cannot be null");
            }

            try {
                // Get message formatter based on the content type
                MessageFormatter formatter = MessageProcessorSelector.getMessageFormatter(msgContext);

                Object o = msgContext.getProperty(MessageContext.TRANSPORT_HEADERS);
                if (o != null && o instanceof Map) {
                    Map headers = (Map) o;

                    String encode = (String) headers.get(HTTP.CONTENT_ENCODING);
                    if (encode != null) {

                        //If message  contains 'Accept-Encoding' header and  if it's value is 'qzip'
                        if (GZIP_CODEC.equals(encode)) {
                            formatter = new GzipMessageFormatterDecorator(formatter);
                        }
                        //if there are any type for 'Accept-Encoding' , those should go here

                    }
                }
                return formatter;

            } catch (AxisFault axisFault) {
                String msg = "Cannot find a suitable MessageFormatter : " + axisFault.getMessage();
                log.error(msg, axisFault);
            }

            return null;

        }
    }