#vulnerable code 
                                protected void checkProviderInfo(ProviderGroup providerGroup) {
        List<ProviderInfo> providerInfos = providerGroup == null ? null : providerGroup.getProviderInfos();
        if (CommonUtils.isEmpty(providerInfos)) {
            return;
        }
        Iterator<ProviderInfo> iterator = providerInfos.iterator();
        while (iterator.hasNext()) {
            ProviderInfo providerInfo = iterator.next();
            if (!StringUtils.equals(providerInfo.getProtocolType(), consumerConfig.getProtocol())) {
                if (LOGGER.isWarnEnabled(consumerConfig.getAppName())) {
                    LOGGER.warnWithApp(consumerConfig.getAppName(),
                        "Unmatched protocol between consumer [{}] and provider [{}].",
                        consumerConfig.getProtocol(), providerInfo.getProtocolType());
                }
            }
            if (StringUtils.isEmpty(providerInfo.getSerializationType())) {
                providerInfo.setSerializationType(consumerConfig.getSerialization());
            }
        }
    } 
                            #location 17 
                            #vulnerability type THREAD_SAFETY_VIOLATION
#fixed code
                                protected void checkProviderInfo(ProviderGroup providerGroup) {
        List<ProviderInfo> providerInfos = providerGroup == null ? null : providerGroup.getProviderInfos();
        if (CommonUtils.isEmpty(providerInfos)) {
            return;
        }
        Iterator<ProviderInfo> iterator = providerInfos.iterator();
        while (iterator.hasNext()) {
            ProviderInfo providerInfo = iterator.next();
            if (!StringUtils.equals(providerInfo.getProtocolType(), consumerConfig.getProtocol())) {
                if (LOGGER.isWarnEnabled(consumerConfig.getAppName())) {
                    LOGGER.warnWithApp(consumerConfig.getAppName(),
                        "Unmatched protocol between consumer [{}] and provider [{}].",
                        consumerConfig.getProtocol(), providerInfo.getProtocolType());
                }
            }
        }
    }