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。
}
        // 
        map.put(Constants.BIND_PORT_KEY, String.valueOf(portToBind));
        // 
        String portToRegistryStr = getValueFromConfig(protocolConfig, Constants.DUBBO_PORT_TO_REGISTRY);
        Integer portToRegistry = parsePort(portToRegistryStr);
        if (portToRegistry == null) {
            portToRegistry = portToBind;
        }
        return portToRegistry;
    }
    private Integer parsePort(String configPort) {
        Integer port = null;
        if (configPort != null && configPort.length() > 0) {
            try {
                Integer intPort = Integer.parseInt(configPort);
                if (isInvalidPort(intPort)) {
                    throw new IllegalArgumentException("Specified invalid port from env value:" + configPort);
                }
                port = intPort;
            } catch (Exception e) {
                throw new IllegalArgumentException("Specified invalid port from env value:" + configPort);
            }
        }
        return port;
    }
    private String getValueFromConfig(ProtocolConfig protocolConfig, String key) {
        String protocolPrefix = protocolConfig.getName().toUpperCase() + "_";
        String port = ConfigUtils.getSystemProperty(protocolPrefix + key);
        if (StringUtils.isEmpty(port)) {