## 类的使用
org.springframework.beans.factory.config.PropertyPlaceholderConfigurer

- 使用PropertyPlaceholderConfigurer的程序包
  程序包 | 说明
  --- | ---
  org.springframework.beans.factory.config | SPI interfaces and configuration-related convenience classes for bean factories.

- - ### org.springframework.beans.factory.config中PropertyPlaceholderConfigurer的使用

    org.springframework.beans.factory.config中PropertyPlaceholderConfigurer的子类
    限定符和类型 | 类和说明
    --- | ---
    `class` | `PreferencesPlaceholderConfigurer` Subclass of PropertyPlaceholderConfigurer that supports JDK 1.4's Preferences API (`java.util.prefs`).