Ribbon的自定义配置(java代码方式)生效条件

第一种方式：将TestConfiguration类放在application启动类上层
第二种方式：将TestConfiguration类放在application启动类同层及以下，
- 需在application启动类上添加注解
```
@ComponentScan(excludeFilters = { @ComponentScan.Filter(type = FilterType.ANNOTATION, value = ExcludeFromComponentScan.class) })
```
- 需在application启动类同层添加接口类ExcludeFromComponentScan.java：
```
package com.mmzs.cloud;

public @interface ExcludeFromComponentScan {

}
```
- 并在ExcludeFromComponentScan.class接口添加注解@ExcludeFromComponentScan;并且注释如下内容：
```
 @Autowired
 IClientConfig config;
```

Ribbon的注意事项

0、Ribbon的自定义配置优先级：

配置文件>java代码>默认配置

1、自定义配置时，@Configuration和@ComponentScan包不应重叠

示例：

    @RibbonClient(name = "microservice-provider-user", configuration = TestConfiguration.class)
    @ComponentScan(excludeFilters = { @ComponentScan.Filter(type = FilterType.ANNOTATION, value = ExcludeFromComponentScan.class) })

2、使用RestTemplate时，想要获得一个List时，应该用数组，而不应该直接用List

[ ] ==错误用法==

    List<User> users = this.restTemplate.getForObject("http://microservice-provider-user/list-all/", List.class);  
    for (User user : users) {
        System.out.println("輸出：" + user.getId() + "+" + user.getUsername());
    }

[x] ==正确用法==

    User[] users = this.restTemplate.getForObject("http://microservice-provider-user/list-all", User[].class);
    List<User> lists = Arrays.asList(users);
    for (User user : lists) {
        System.out.println("輸出：" + user.getId() + "+" + user.getUsername());
    }