### Environment

* Dubbo version: 2.7.4.1
* Operating System version: macOS Catalina Version 10.15.3
* Java version: 1.8.0_231

### Steps to reproduce this issue

1. 通过telnet调用接口如下
方法(Method)
`public String convert7(UserInfoCondition userInfoCondition) {  }`
参数(Parameter)
`public class UserInfoCondition {
    private List<Map<Integer, UserInfo>> userList;
}`
`public class UserInfo {
    private String accountMobile;
    private String userPassword;
}`

invoke UsesrInfoFacade.convert7({"userList":[{"1":{"accountMobile":"15052234567"}}]})
or
invoke UsesrInfoFacade.convert7({"userList":[{1:{"accountMobile":"15052234567"}}]})

提示如下错误(has a problem)
![image](https://user-images.githubusercontent.com/17045745/77892951-ebd50d00-72a5-11ea-95b0-dd59a68a83cc.png)

到底如何书写这个入参呢?(How to write the parameters)


return CompatibleTypeUtils.compatibleTypeConvert(pojo, type);
        }
        Object o = history.get(pojo);
        if (o != null) {
            return o;
        }
        history.put(pojo, pojo);
        if (pojo.getClass().isArray()) {
            if (Collection.class.isAssignableFrom(type)) {
                Class<?> ctype = pojo.getClass().getComponentType();
                int len = Array.getLength(pojo);
                Collection dest = createCollection(type, len);
                history.put(pojo, dest);
                for (int i = 0; i < len; i++) {
                    Object obj = Array.get(pojo, i);
                    Object value = realize0(obj, ctype, null, history);
                    dest.add(value);
                }
                return dest;
            } else {
                Class<?> ctype = (type != null && type.isArray() ? type.getComponentType() : pojo.getClass().getComponentType());
                int len = Array.getLength(pojo);
                Object dest = Array.newInstance(ctype, len);
                history.put(pojo, dest);
                for (int i = 0; i < len; i++) {
                    Object obj = Array.get(pojo, i);
                    Object value = realize0(obj, ctype, null, history);
                    Array.set(dest, i, value);
                }
                return dest;