运用单例模式思想解决RuntimeException超时问题

今天，排查了一个RuntimeException超时问题，简单记录分享下。
分析关键日志排查如下

查看关键代码

    private static Client createClient(String wsdlUrl) {
        JaxWsDynamicClientFactory jaxWsDynamicClientFactory = JaxWsDynamicClientFactory.newInstance();
        return jaxWsDynamicClientFactory.createClient(wsdlUrl);
    }

发现，原来这是同事比较久，之前的代码，这相当于来一次就newInstance一次，于是改造下

    private static final Map<String, Client> CLIENT_MAP = new ConcurrentHashMap<>();

    /**
     * 创建ws客户端
     *
     * @param wsdlUrl
     * @return
     */
    public static Client createClient(String wsdlUrl) {
        Client client;
        if (!CLIENT_MAP.containsKey(wsdlUrl)) {
            synchronized (CLIENT_MAP) {
                if (!CLIENT_MAP.containsKey(wsdlUrl)) {
                    JaxWsDynamicClientFactory jaxWsDynamicClientFactory = JaxWsDynamicClientFactory.newInstance();
                    client = jaxWsDynamicClientFactory.createClient(wsdlUrl);
                    CLIENT_MAP.put(wsdlUrl, client);
                } else {
                    client = CLIENT_MAP.get(wsdlUrl);
                }
            }
        } else {
            client = CLIENT_MAP.get(wsdlUrl);
        }
        return client;
    }

用ConcurrentHashMap存储一下，每次都先从map里面拿，不难看出，其实这里和单例思想是一样的。