Apollo实现@ConfigurationProperties配置刷新的另外一种方式

背景

目前apollo官方实现@ConfigurationProperties须要配合使用EnvironmentChangeEvent或RefreshScope（须要引入springCloud-context）,考虑一种简单的实现方式以下：java

思路

监听apollo配置刷新事件，而后经过spring的工具类获取当前配置类的bean实例对象（单例），经过反射将对应改变的配置项注入配置类bean实例。git

代码实现

@Data
@Slf4j
@Configuration
@ConfigurationProperties
@EnableApolloConfig
public class AppConfig {

    private Map<String, String> xxConfigMap;

    @ApolloConfigChangeListener
    public void onChange(ConfigChangeEvent changeEvent) {
        //this.applicationContext.publishEvent(new EnvironmentChangeEvent(changeEvent.changedKeys()));
   changeEvent.changedKeys().stream().map(changeEvent::getChange).forEach(change -> {
            log.info("Found change - key: {}, oldValue: {}, newValue: {}, changeType: {}", change.getPropertyName(), change.getOldValue(), change.getNewValue(), change.getChangeType());
            String vKey = change.getPropertyName();
            String newValue = change.getNewValue();
            if (vKey.contains(".")) {
                //取出对应的field 反射从新赋值
                AppConfig appConfig = SpringContext.getBean(AppConfig.class);
                try {
                    PropertyDescriptor propertyDescriptor = new PropertyDescriptor(vKey.substring(0, vKey.indexOf(".")), appConfig.getClass());
                    Map<String, String> map = (Map<String, String>) propertyDescriptor.getReadMethod().invoke(appConfig);
                    map.put(vKey.substring(vKey.indexOf(".")+1,vKey.length()), newValue);
                    propertyDescriptor.getWriteMethod().invoke(appConfig, map);
                } catch (Exception e) {
                    log.error("replace field {} error", vKey);
                }
            }
        });
    }


    //测试是否生效
    @PostConstruct
    void test() {
        Executors.newSingleThreadExecutor().submit(() -> {
            while (true) {
                log.info(xxConfigMap.toString());
                Thread.sleep(2000);
            }
        });
    }
}

Reference

apollo wiki spring-boot集成方式github