Class PropertyPlaceholderHelper的使用

1.代码

 private static Properties properties = new Properties();

 public static String getProperties(String key) {
         PropertyPlaceholderHelper propertyPlaceholderHelper = new PropertyPlaceholderHelper(PlaceholderConfigurerSupport.DEFAULT_PLACEHOLDER_PREFIX, PlaceholderConfigurerSupport.DEFAULT_PLACEHOLDER_SUFFIX);
         if(properties.containsKey(key)){
             return propertyPlaceholderHelper.replacePlaceholders(PlaceholderConfigurerSupport.DEFAULT_PLACEHOLDER_PREFIX + key + PlaceholderConfigurerSupport.DEFAULT_PLACEHOLDER_SUFFIX, properties);
         }else{
             return "";
         }
     }