如何在Spring中为yml中的属性使用key中的变量

app:
  name: MyApp
  version: 1.0

<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
  <property name="locations">
    <list>
      <value>classpath:application.yml</value>
    </list>
  </property>
</bean>

<bean id="myBean" class="com.example.MyBean">
  <property name="appName" value="${app.name}" />
  <property name="appVersion" value="${app.version}" />
</bean>

public class MyBean {
  private String appName;
  private String appVersion;

  // 省略构造函数和其他方法

  public void printAppInfo() {
    System.out.println("App Name: " + appName);
    System.out.println("App Version: " + appVersion);
  }
}

app:
  name: MyApp
  version: 1.0

@Component
public class MyBean {
  @Value("${app.name}")
  private String appName;

  @Value("${app.version}")
  private String appVersion;

  // 省略构造函数和其他方法

  public void printAppInfo() {
    System.out.println("App Name: " + appName);
    System.out.println("App Version: " + appVersion);
  }
}