src/org/nutz/mvc/impl/ActionInvoker.java
public void addChain(String httpMethod, ActionChain chain) {
        if (Strings.isBlank(httpMethod))
            throw Lang.makeThrow("chain need a valid HTTP Method, but is is '%s'", httpMethod);
        ActionChain old = chainMap.put(httpMethod.toUpperCase(), chain);
        if (old != null) {
            log.warnf("Duplicate @At mapping with same HttpMethod");
        }
    }
public void addChain(String httpMethod, ActionChain chain) {
        if (Strings.isBlank(httpMethod))
            throw Lang.makeThrow("chain need a valid HTTP Method, but is is '%s'", httpMethod);
        ActionChain old = chainMap.put(httpMethod.toUpperCase(), chain);
        if (old != null) {
            log.warnf("Duplicate @At mapping with same HttpMethod");
        }
    }
增加 ActionChain

@param httpMethod
HTTP 的请求方法 (GET|POST|PUT|DELETE),如果为空，则会抛错
@param chain
动作链