#vulnerable code 
                                public void executeSendMessageHookBefore(final ChannelHandlerContext ctx, final RemotingCommand request,
                                             SendMessageContext context) {
        if (hasSendMessageHook()) {
            for (SendMessageHook hook : this.sendMessageHookList) {
                try {
                    final SendMessageRequestHeader requestHeader = parseRequestHeader(request);

                    if (null != requestHeader) {
                        context.setProducerGroup(requestHeader.getProducerGroup());
                        context.setTopic(requestHeader.getTopic());
                        context.setBodyLength(request.getBody().length);
                        context.setMsgProps(requestHeader.getProperties());
                        context.setBornHost(RemotingHelper.parseChannelRemoteAddr(ctx.channel()));
                        context.setBrokerAddr(this.brokerController.getBrokerAddr());
                        context.setQueueId(requestHeader.getQueueId());
                    }

                    hook.sendMessageBefore(context);
                    requestHeader.setProperties(context.getMsgProps());
                } catch (Throwable e) {
                }
            }
        }
    } 
                            #location 19 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                public void executeSendMessageHookBefore(final ChannelHandlerContext ctx, final RemotingCommand request,
                                             SendMessageContext context) {
        if (hasSendMessageHook()) {
            for (SendMessageHook hook : this.sendMessageHookList) {
                try {
                    final SendMessageRequestHeader requestHeader = parseRequestHeader(request);

                    if (null != requestHeader) {
                        context.setProducerGroup(requestHeader.getProducerGroup());
                        context.setTopic(requestHeader.getTopic());
                        context.setBodyLength(request.getBody().length);
                        context.setMsgProps(requestHeader.getProperties());
                        context.setBornHost(RemotingHelper.parseChannelRemoteAddr(ctx.channel()));
                        context.setBrokerAddr(this.brokerController.getBrokerAddr());
                        context.setQueueId(requestHeader.getQueueId());
                    }

                    hook.sendMessageBefore(context);
                    if (requestHeader != null) {
                        requestHeader.setProperties(context.getMsgProps());
                    }
                } catch (Throwable e) {
                    // Ignore
                }
            }
        }
    }