如何在服务器启动后更新spring属性placeholder值

从DB启动服务器后，我需要更新或刷新属性占位符值。 正如我在下面的子类中扩展使用自定义PropertyPlaceHolderConfigure一样

自定义属性PlaceHolderConfiguration类：

public class PropertiesSourceImpl extends PropertyPlaceholderConfigurer{    
 private static final Logger logger = Logger.getLogger(PropertiesSourceImpl.class);
 public PropertiesSourceImpl(){  }
 private int springSystemPropertiesMode =  SYSTEM_PROPERTIES_MODE_OVERRIDE;

 private static Map<String, String> propertiesMap;
    @Override
    public void setSystemPropertiesMode(int systemPropertiesMode) {
    String updatedValue = loadFromDB();
        System.setProperty("newKey", updatedValue);
        super.setSystemPropertiesMode(systemPropertiesMode);
        springSystemPropertiesMode = systemPropertiesMode;
    }      

    public void loadProperties(Properties props) throws IOException {       
    String updatedValue = loadFromDB();
        props.setProperty("newKey", updatedValue); 

        super.loadProperties(props);

        propertiesMap = new HashMap<String, String>();
        for (Object key : props.keySet()) {
            String keyStr = key.toString();

            String valueStr = resolvePlaceholder(keyStr, props);

            propertiesMap.put(keyStr, valueStr);                
        }           
      }

    public static String getProperty(String name) {
        return propertiesMap.get(name).toString();
    }       
    public void postProcessBeanFactory(BeanFactory factory){
        super.postProcessBeanFactory((ConfigurableListableBeanFactory) factory);
    }
}

public class myBean{


public void updatePropertValue(){

    Properties props=new Properties();
    props.setProperty("newKey", "updatedValue");         

    PropertyPlaceholderConfigurer configurer = new PropertyPlaceholderConfigurer();
    configurer.setProperties(props);
    //configurer.setSystemPropertiesMode(springSystemPropertiesMode);

    ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext(new String[]{"context.xml"}, false);      
    configurer.setIgnoreUnresolvablePlaceholders(true);
    configurer.setSearchSystemEnvironment(false);
    //configurer.postProcessBeanFactory(applicationContext.getBeanFactory());
    applicationContext.addBeanFactoryPostProcessor(configurer);
    applicationContext.refresh();
}
}

但值仍然是而不是更新uerManagementServiceImpl中的值

---

请让我知道我的代码中有什么错误，以便为属性占位符设置更新的值。

如何检查属性是否已更新？要检查值，需要在UserManagementServiceImpl.java的构造函数中添加getNewKey（）

public class myBean{


public void updatePropertValue(){

    Properties props=new Properties();
    props.setProperty("newKey", "updatedValue");         

    PropertyPlaceholderConfigurer configurer = new PropertyPlaceholderConfigurer();
    configurer.setProperties(props);
    //configurer.setSystemPropertiesMode(springSystemPropertiesMode);

    ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext(new String[]{"context.xml"}, false);      
    configurer.setIgnoreUnresolvablePlaceholders(true);
    configurer.setSearchSystemEnvironment(false);
    //configurer.postProcessBeanFactory(applicationContext.getBeanFactory());
    applicationContext.addBeanFactoryPostProcessor(configurer);
    applicationContext.refresh();
}
}