2.7.0版本getContextPath方法：
```
protected String getContextPath(URL url) {
        String contextPath = url.getPath();
        return contextPath.endsWith("/") ? contextPath.substring(0,contextPath.length()-1) : contextPath;
    }
```
无法将方法置入web容器中，退回2.6.5版本的方法：
```
protected String getContextPath(URL url) {
        int pos = url.getPath().lastIndexOf("/");
        return pos > 0 ? url.getPath().substring(0, pos) : "";
    }
```
使用正常，两个方法应该不等价的。
return 9090;
    }
    public Map<URL, NotifyListener> getOverrideListeners() {
        return overrideListeners;
    }
    public void register(URL registryUrl, URL registeredProviderUrl) {
        Registry registry = registryFactory.getRegistry(registryUrl);
        registry.register(registeredProviderUrl);
    }
    public void unregister(URL registryUrl, URL registeredProviderUrl) {
        Registry registry = registryFactory.getRegistry(registryUrl);
        registry.unregister(registeredProviderUrl);
    }
    @Override
    public <T> Exporter<T> export(final Invoker<T> originInvoker) throws RpcException {
        URL registryUrl = getRegistryUrl(originInvoker);
        
        URL providerUrl = getProviderUrl(originInvoker);
        
        
        
        
        final URL overrideSubscribeUrl = getSubscribedOverrideUrl(providerUrl);
        final OverrideListener overrideSubscribeListener = new OverrideListener(overrideSubscribeUrl, originInvoker);
        overrideListeners.put(overrideSubscribeUrl, overrideSubscribeListener);
        providerUrl = overrideUrlWithConfig(providerUrl, overrideSubscribeListener);
        
        final ExporterChangeableWrapper<T> exporter = doLocalExport(originInvoker, providerUrl);
        
        final Registry registry = getRegistry(originInvoker);