* Nacos中配置是作为Spring上下文enviroment的属性源之一，获取属性时会收到其他属性源的干扰，比如通过JVM参数和环境变量注入的属性优先级比Nacos中的更高
    * 通过spring.config.import导入多个Nacos配置时，其中相同的key对应的属性只会有一个生效，需要控制多个属性源的key不重复或者处理因优先级问题导致的属性覆盖问题。无法精准获取指定Nacos配置中的属性
    * 无法将Nacos配置自动注入对象类型的字段
    * 只能被动接受配置最终内容，无法在配置变更时对配置进行二次处理或者触发其他业务动作，无法感知指定的属性变更前后的详细信息
    * 通过@Value注解引用的配置要支持动态刷新，需要在SpringBean上添加@RefreshScope，配置更新时会先将Bean销毁再重新创建新的Bean，使用不当易产生线上问题。

- @NacosConfig：作用于SpringBean的字段，将Nacos中指定的配置注入字段；作用于SpringBean Class，将Nacos中指定的配置注入Bean的属性中；作用于FactoryBean 方法，将Nacos中指定的配置注入Bean的属性中，不依赖RefreshScope注解即可生效。
- @NacosConfigListener：作用于SpringBean的方法，在Nacos中的配置发生变化时，以方法参数形式接受变更后的最新配置内容，支持以对象类型接收结果。
- @NacosConfigKeysListener：作用于SpringBean的方法，在Nacos中的配置的指定属性key集合发生变化时，以方法参数ConfigChangeEvent接受变更前后的属性值。

@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD, ElementType.TYPE, ElementType.METHOD})
@Documented
public @interface NacosConfig {

    String group();

    String dataId();

    String key() default "";

    String defaultValue() default "";
}

@NacosConfig(dataId = "SampleApp.application.properties", group = "default")
String configContent;

@NacosConfig(dataId = "SampleApp.application.properties", group = "default", key = "useCache", defaultValue = "false")
boolean booleanValue;

@NacosConfig(dataId = "scoreintArray.json", group = "default")
int[] scores;

@NacosConfig(dataId = "SampleApp.application.properties", group = "default")
Properties properties = new Properties();

@NacosConfig(dataId = "myobject.json", group = "default")
MyObject json2Object;

@NacosConfig(dataId = "myobjectArray.json", group = "default")
MyObject[] json2ObjectArray;

@NacosConfig(dataId = "myobjectArray.json", group = "default")
List<MyObject> json2ObjectList;

@NacosConfig(dataId = "myobjectMap.json", group = "default")
Map<String, MyObject> json2ObjectMap;

@Component
@NacosConfig(dataId = "myobject.json", group = "default")
public class MyObject {

    String name;

    String age;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAge() {
        return age;
    }

    public void setAge(String age) {
        this.age = age;
    }
}

public class SampleConfiguration {

  @NacosConfig(dataId = "myobject1.json", group = "default")
  @Bean
  public MyObject bean1(){
    return new MyObject();
  }

  @NacosConfig(dataId = "myobject2.json", group = "default")
  @Bean
  public MyObject bean2(){
    return new MyObject();
  }

}

@NacosConfigListener(dataId = "myobjectArray.json", group = "default")
private void fullContentChanged(String content) {
    System.out.println("receive ：" + content);
}

@NacosConfigListener(dataId = "SampleApp.application.properties", group = "default",key="score")
private void scoreChanged(int score) {
    System.out.println("receive ：" + score);
}

@NacosConfigListener(dataId = "scoresArray.json", group = "default")
private void scoresChanged(int[] scores) {
    System.out.println("receive ：" + scores);
}

@NacosConfigListener(dataId = "SampleApp.application.properties", group = "default")
private void propertiesChanged(Properties properties) {
    System.out.println("receive ：" + properties);
}

    @NacosConfigListener(dataId = "myobject.json", group = "default")
    private void myObjectChanged(MyObject object) {
        System.out.println("receive ：" + object);
    }

    @NacosConfigListener(dataId = "myobjectArray.json", group = "default")
    private void myObjectArrayChanged(MyObject[] objectArray) {
        System.out.println("receive ：" + objectArray);
    }

    @NacosConfigListener(dataId = "myobjectArray.json", group = "default")
    private void myObjectListChanged(List<MyObject> objectList) {
        System.out.println("receive ：" + objectList);
    }

    @NacosConfigListener(dataId = "myobjectMap.json", group = "default")
    private void myObjectMapChanged(Map<String,MyObject> objectMap) {
        System.out.println("receive ：" + objectMap);
    }

@NacosConfigKeysListener(dataId = "SampleApp.122110test.properties", group = "default", interestedKeys = {
        "useLocalCache,"}, interestedKeyPrefixes = {"122110."})
private void onKeysChangeSingle(ConfigChangeEvent changeEvent) {
    System.out.println("interestedKeyPrefixes:nacos." + changeEvent.getChangeItems());
}

#pom.xml中引入spring-alibaba-nacos-config依赖
<dependency>
      <groupId>com.alibaba.cloud</groupId>
      <artifactId>spring-alibaba-nacos-config</artifactId>
      <version>2023.0.3.2</version>
</dependency>

#application.properties中添加如下配置
spring.config.import=nacos:optional:nacos:{此处按需替换为需导入的nacos dataId}?group={此处按需替换为需导入的nacos group}&refreshEnabled=true
spring.nacos.config.server-addr={此处按需替换为nacos的serverAddr}
spring.nacos.config.namespace={此处按需替换为nacos的命名空间，public请填空}

//其他参数请参照sca官方文档，将spring.cloud.nacos前缀替换为spring.nacos即可,本文中的注解用法完全一致